Showing 1–50 of 216 results for author: De Petris, M

LiteBIRD Mission Overview after Mission Reformation

Authors: LiteBIRD Collaboration, K. Aizawa, H. Akamatsu, R. Akizawa, E. Allys, A. Anand, D. Audley, J. Aumont, S. Azzoni, C. Baccigalupi, M. Ballardini, A. J. Banday, G. Barbieri Ripamonti, R. B. Barreiro, N. Bartolo, S. Basak, M. Bersanelli, A. Besnard, D. Blinov, F. Bouchet, F. Boulanger, N. Brancadori, T. Brinckmann, E. Calabrese, P. Campeti , et al. (150 additional authors not shown)

Abstract: LiteBIRD is a JAXA-led space mission designed to produce all-sky microwave polarization maps. Its primary science goal is to test representative inflationary models by measuring the cosmic microwave background $B$-mode polarization generated by primordial gravitational waves, while also providing new insights into cosmology, particle physics, and astrophysics. The mission concept has been updated… ▽ More LiteBIRD is a JAXA-led space mission designed to produce all-sky microwave polarization maps. Its primary science goal is to test representative inflationary models by measuring the cosmic microwave background $B$-mode polarization generated by primordial gravitational waves, while also providing new insights into cosmology, particle physics, and astrophysics. The mission concept has been updated following the reformation activities initiated after the Mission Definition Review in 2024. The current concept preserves the central scientific objectives, while simplifying the payload configuration: a single telescope covers 12 frequency bands with band centers spanning 40 to 402~GHz, corresponding to an optical coverage of 34--448~GHz. The telescope is a cross-Dragone reflector with a 500~mm aperture diameter, cooled to approximately 5~K and coupled to transition-edge-sensor bolometer arrays operated at 0.1~K. LiteBIRD will observe from a Lissajous orbit around the Sun--Earth L2 point during a nominal 3-year survey. More specifically, the primary scientific objective is to achieve total uncertainty in the tensor-to-scalar ratio of $δr < 0.002$ (68\% C.L.), including contributions from foreground residuals, statistical uncertainties, instrumental systematics, and margin contingency. The corresponding map-noise requirements are specified separately for the low-, mid-, and high-frequency ranges over the reionization and recombination multipole ranges. This sensitivity makes LiteBIRD unique not only for inflationary science but also for a broad range of scientific investigations probing the history of both the early and late Universe, as well as for astrophysical processes, including Galactic science. This paper summarizes the scientific objectives, updated payload and instrument concepts, observation strategy, and ground segment plans. △ Less

Submitted 28 July, 2026; originally announced July 2026.

Comments: 11 pages, 3 figures, 2 tables. SPIE Astronomical Telescopes + Instrumentation 2026

The Three Hundred project: Low Gas Fraction Galaxy Clusters properties and their environment

Authors: Francesco Guidi, Marco De Petris, Sara Santoni, Raphael Wicker, Antonio Ferragamo, Hippolyte Froget, Stefano Andreon, Weiguang Cui, Elena Rasia, Gustavo Yepes

Abstract: Galaxy cluster samples based on X-ray and Sunyaev-Zel'dovich (SZ) observations are affected by selection biases. These catalogs preferentially include systems with high gas content and surface brightness. Excluding objects with depleted gas content, low-gas-fraction clusters (LGFCs), could lead to an incomplete sampling. We aim to investigate the abundance and the properties of the LGFCs populatio… ▽ More Galaxy cluster samples based on X-ray and Sunyaev-Zel'dovich (SZ) observations are affected by selection biases. These catalogs preferentially include systems with high gas content and surface brightness. Excluding objects with depleted gas content, low-gas-fraction clusters (LGFCs), could lead to an incomplete sampling. We aim to investigate the abundance and the properties of the LGFCs population using The Three Hundred hydrodynamical simulations, focusing on the Gadget-X code. In particular, we study outliers in the $f_{\mathrm{g},500} - M_{500}$ relation, environmental influences, and their behavior in key scaling relations, with a focus on the Compton-Y observable. We analyze a sample of $N_{\mathrm{tot}} = 9858$ simulated objects from The Three Hundred, in the redshift band $z \in [0;0.817]$. LGFCs are selected statistically as outliers of the $f_{\mathrm{g},500}-M_{500}$ relation. To analyze environmental effects, we compare the gas density and temperature radial profiles of LGFCs against the No-LGFCs population. Finally, we study how the temperature, entropy, and spherical Compton parameter scaling relations are affected by the inclusion of LGFCs. We find that LGFCs are preferentially found at the low-mass end and their abundance increases toward low redshift. Radial profiles of LGFCs show lower gas concentrations in the core regions and higher temperatures, suggesting a more diffuse and heated ICM. This behavior is also reflected in the entropy scaling relation, where LGFCs are extreme positive outliers. Contrary to observations, the $Y_{\mathrm{sph},500}$ values of LGFCs show no significant deviation from the general population. Nevertheless, we cannot rule out that these differences are partly driven by the mass incompleteness at the low-mass end and the environmental bias of our simulated sample. △ Less

Submitted 15 July, 2026; v1 submitted 14 July, 2026; originally announced July 2026.

The Three Hundred Project: Validating $H_0$ inference from mock X-ray and millimetre analyses of galaxy clusters

Authors: F. De Luca, H. Bourdin, P. Mazzotta, E. Rasia, A. Kozmanyan, W. Cui, M. De Petris, D. de Andres, G. Yepes

Abstract: Measurements of thermodynamical quantities in galaxy clusters are differently affected by simplified modelling of radially averaged observables in the X-ray and millimetre bands. This includes assumptions about the cosmological model and the morphology of the cluster intracluster medium (ICM). Within a large sample of clusters extracted from The Three Hundred hydrodynamical simulations, we assess… ▽ More Measurements of thermodynamical quantities in galaxy clusters are differently affected by simplified modelling of radially averaged observables in the X-ray and millimetre bands. This includes assumptions about the cosmological model and the morphology of the cluster intracluster medium (ICM). Within a large sample of clusters extracted from The Three Hundred hydrodynamical simulations, we assess the systematic differences expected from the morphological assumptions between ICM temperatures as inferred from X-ray spectroscopy or joint X-ray and millimetre imaging. We find that these differences show a well-defined statistical behaviour that correlates with the cluster dynamical and morphological indicators. We then investigate how joint inferences of cluster temperature profiles, a priori informed by this statistical behaviour, allow us to constrain cosmological parameters inferred from the apparent cluster sizes. Assuming a flat $Λ$ cold dark matter ($Λ$CDM) cosmology and priors on $Ω_\mathrm{m}$ and the helium abundance, this method provides us with unbiased estimates of the Hubble constant, $H_0$, characterised with a precision of about $4\%$ and $1.5\%$ for samples of 100 and 1000 clusters, respectively, and ultimately limited by systematic uncertainties of about $0.6$--$0.8\, {\rm km\, s^{-1} Mpc^{-1}}$. This work highlights the potential of joint X-ray and millimetre observations of galaxy cluster samples to place tight constraints on $H_0$. △ Less

Submitted 21 July, 2026; v1 submitted 9 July, 2026; originally announced July 2026.

Comments: Accepted for publication in A&A

The NIKA2 Cosmological Legacy Survey in COSMOS: Final 1.2mm and 2mm source catalogs and redshift distribution of dusty star-forming galaxies

Authors: C. R. Carvajal-Bohorquez, G. Lagache, A. Beelen, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, M. Aravena, H. Aussel, A. Benoît, S. Berta, M. Béthermin, L. -J. Bing, A. Bongiovanni, J. Bounmy, O. Bourrion, M. Calvo, Caitlin M. Casey, A. Catalano, D. Chérouvrier, U. Chowdhury, M. De Petris, F. -X. Désert, S. Doyle , et al. (42 additional authors not shown)

Abstract: We present the final 1.2mm and 2mm source catalogs and the redshift distribution of the mm-selected population from the NIKA2 Cosmological Legacy Survey (N2CLS) in the COSMOS field. Our aim is to provide a comprehensive dataset for studying the physical properties and evolution of high-redshift DSFGs. N2CLS covers ~1070 arcmin2 with median noise levels of 315$μ$Jy and 91$μ$Jy at 1.2 and 2mm, respe… ▽ More We present the final 1.2mm and 2mm source catalogs and the redshift distribution of the mm-selected population from the NIKA2 Cosmological Legacy Survey (N2CLS) in the COSMOS field. Our aim is to provide a comprehensive dataset for studying the physical properties and evolution of high-redshift DSFGs. N2CLS covers ~1070 arcmin2 with median noise levels of 315$μ$Jy and 91$μ$Jy at 1.2 and 2mm, respectively. Sources are extracted with a S/N threshold of 3.9, ensuring >80% purity. Multi-wavelength counterparts are identified using high-resolution interferometric (sub-)mm data (NOEMA, ALMA) and radio observations (VLA, MeerKAT). Redshifts are compiled from spectroscopic and photometric catalogs (e.g., COSMOSWeb). The N2CLS master catalog includes 323 sources detected at >80% purity, with 104 sources detected in both bands, 197 only at 1.2mm, and 22 only at 2mm. Multi-wavelength identifications are secured for ~89% of the sample. The redshift distribution of 1.2mm sources peaks at 2.8$\pm$0.1, consistent with the epoch of peak cosmic star formation. In the total sample, we lack redshift for ~2% of the identified galaxies, plus 34 sources for which no accurate positional proxy is available, preventing the identification of a multi-wavelength counterpart. We identify 66 galaxies at z>4. The observed redshift distribution agrees well with the SIDES simulations, while four other galaxy evolution models are statistically inconsistent with the data. N2CLS is the largest contiguous deep survey to date with this depth and homogeneous coverage. This homogeneous coverage is important, as 25% of N2CLS sources lack a SCUBA2 850 mic counterpart, likely because the strongly non-uniform noise distribution of the SCUBA2 map results in lower sensitivity in parts of the field.The released data products provide a legacy dataset for studying dust-obscured galaxy evolution. △ Less

Submitted 1 May, 2026; originally announced May 2026.

Comments: Submitted to A&A on 30 April. Some of the data are already available at https://data.lam.fr/n2cls; the remainder will be made available upon acceptance

The Three Hundred project: cosmic web identification from 2D gas and Compton-$y$ maps of galaxy clusters outskirts

Authors: Sara Santoni, Marco De Petris, Gustavo Yepes, Weiguang Cui, Daniel de Andrés, Antonio Ferragamo, Raphaël Wicker

Abstract: Galaxy clusters are located at the nodes of the filamentary network known as the cosmic web. A more comprehensive understanding of galaxy clusters can be achieved by considering their environment, in particular, the filamentary structures to which they are connected. In this work, we aim to assess the reliability of the cosmic web reconstruction from mock observational data. In particular, we aim… ▽ More Galaxy clusters are located at the nodes of the filamentary network known as the cosmic web. A more comprehensive understanding of galaxy clusters can be achieved by considering their environment, in particular, the filamentary structures to which they are connected. In this work, we aim to assess the reliability of the cosmic web reconstruction from mock observational data. In particular, we aim to quantify the effects of the 2D projection relative to the underlying 3D network and the impact of using the Sunyaev-Zel'dovich (SZ) effect as a tracer of the cosmic web. We reconstruct the filamentary networks in the outskirts of The Three Hundred simulated clusters with the filament finder DisPerSE. First, we extract the networks from the 2D gas distribution and evaluate their purity and completeness with respect to the 3D networks projected along the line of sight. We also compute the distances between the corresponding skeletons. Moreover, we identify filaments from simulated Compton-$y$ maps of the clusters at redshift $z=0$, and we compare them with the 2D gas network. The skeletons extracted from 2D maps provide good representations of the underlying 3D ones, both in terms of critical points and filaments. We find a median distance between the spines of the 2D and projected 3D networks of approximately $0.22 \, h^{-1}$ Mpc, although the connectivity derived from the 2D networks is slightly underestimated. We observe a good spatial agreement between the gas and SZ networks, with a median distance of $\approx 0.24 \, h^{-1}$ Mpc. Finally, we show that gas outside galaxy clusters is preferentially located in filamentary structures, which contribute $\sim 80\%$ of the integrated Compton-$Y$ parameter of clusters' outskirts. △ Less

Submitted 27 April, 2026; originally announced April 2026.

Comments: 11 pages, 9 figures

GASTON-GP: Source catalogue and millimetre variability of massive protostellar objects

Authors: Ji-Xuan Zhou, Nicolas Peretto, A. J. Rigby, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, H. Aussel, A. Bacmann, A. Beelen, A. Benoît, S. Berta, M. Béthermin, A. Bongiovanni, J. Bounmy, O. Bourrion, M. Calvo, A. Catalano, D. Chérouvrier, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen, G. Ejlali , et al. (34 additional authors not shown)

Abstract: The processes governing protostellar mass growth remain debated, although episodic accretion is now understood as a key feature of protostellar evolution across all masses. Luminosity bursts have been observed in both low- and high-mass protostars, but the overall statistics remain limited, especially for high-mass objects. Over the past decade, numerical simulations of high-mass core collapse hav… ▽ More The processes governing protostellar mass growth remain debated, although episodic accretion is now understood as a key feature of protostellar evolution across all masses. Luminosity bursts have been observed in both low- and high-mass protostars, but the overall statistics remain limited, especially for high-mass objects. Over the past decade, numerical simulations of high-mass core collapse have provided a theoretical framework for interpreting protostellar variability, yet additional observational constraints are required to determine the characteristics and importance of bursts. In this work, we analyse data from GASTON-GP programme, which mapped a 2.4 square degrees region of the Galactic plane (centred at l = 24 deg) at 1.15 and 2.00 mm using NIKA2 on the IRAM 30 m telescope. The survey obtained 11 epochs over four years, offering the first opportunity to study millimetre variability in a large sample of massive protostellar sources. From the combined dataset, we constructed catalogues of 2925 compact sources at 1.15 mm and 1713 at 2.00 mm. Using a dedicated relative calibration scheme, we generated millimetre light curves for around 200 high-signal-to-noise sources and identified one variable candidate. However, it is not protostellar. Consequently, we report no robust detections of variable protostellar sources in GASTON field. This is the direct consequence of observational limitations (i.e., sensitivity, resolution) combined with the lack of any 100-fold luminosity bursts during the observations, which is consistent with estimates inferred from isolated core collapse simulations. This study highlights the need for future high-resolution, high-cadence surveys to constrain the accretion histories of massive protostars. △ Less

Submitted 6 March, 2026; v1 submitted 5 March, 2026; originally announced March 2026.

Comments: Accepted by MNRAS, one plot updated

Journal ref: Mon Not R Astron Soc (2026)

CHEX-MATE: Are we getting cluster thermodynamics right?

Authors: R. Seppi, D. Eckert, E. Rasia, S. T. Kay, K. Dolag, V. Biffi, Y. E. Bahar, H. Bourdin, F. De Luca, M. De Petris, S. Ettori, M. Gaspari, F. Gastaldello, V. Ghirardini, L. Lovisari, P. Mazzotta, G. W. Pratt, E. Pointecouteau, M. Rossetti, J. Sayers, M. Sereno, G. Yepes

Abstract: Galaxy clusters offer powerful insights into the large-scale structure of the Universe and the physics of baryons in hot state. Their scientific exploitation, however, hinges on our ability to accurately measure key thermodynamic properties. In this work, we aim to assess the reliability of current analysis techniques in reconstructing these properties, with particular focus on samples similar to… ▽ More Galaxy clusters offer powerful insights into the large-scale structure of the Universe and the physics of baryons in hot state. Their scientific exploitation, however, hinges on our ability to accurately measure key thermodynamic properties. In this work, we aim to assess the reliability of current analysis techniques in reconstructing these properties, with particular focus on samples similar to those observed in the Cluster HEritage project with XMM-Newton (CHEX-MATE). We develop a suite of dedicated end-to-end simulations of CHEX-MATE-like clusters selected from large scale hydrodynamical simulations, and processed through a newly developed realistic XMM-Newton simulator. We apply a full X-ray data analysis pipeline to the mock datasets, including imaging, spectral fitting, and profile reconstruction. The gas density profiles can be robustly recovered across a wide radial range, when using azimuthal mean surface brightness profiles. Our reconstruction techniques are able to reproduce the intrinsic density profile with the correct scatter, with deviations of at most 10% between 0.1 and 1xR500c. The gas mass is reconstructed with better than 1% accuracy. Accurate measurement of temperature profiles is more challenging and possibly subject to biases, particularly in the presence of azimuthal variations and multi-temperature gas along the line of sight, which dominate over projection effects. Our results highlight the need for caution in interpreting cluster temperature measurements and underscore the value of tailored mock observations for understanding observational systematics. These findings also suggest that biases in X-ray temperature measurements may alter the interpretation of the thermodynamical state of the intra-cluster medium, an outlook particularly relevant in light of recent low velocity measurements from the XRISM mission. △ Less

Submitted 3 March, 2026; originally announced March 2026.

Comments: Submitted to A&A

Intracluster Medium Fluctuations on Scales up to 1 Mpc: A Combined eROSITA and SPT/Planck Analysis of Abell 3266

Authors: H. Saxena, A. Heinrich, J. Sayers, I. Zhuravleva, E. Bulbul, J. Sanders, C. Avestruz, R. Basu Thakur, E. Battistelli, A. Botteon, F. Cacciotti, F. Columbro, A. Coppolecchia, S. Cray, P. de Bernardis, M. De Petris, L. Lamagna, E. T. Lau, S. Masi, A. Paiella, F. Piacentini, E. Rapaport, L. Rudnick, D. White, J. ZuHone

Abstract: Galaxy clusters form through hierarchical assembly, where smaller substructures merge to build the largest gravitationally bound objects in the universe. These mergers, combined with feedback from AGN, filamentary accretion, and other energy injection processes, generate turbulence and perturbations within the intra-cluster medium (ICM). X-ray and Sunyaev-Zel'dovich (SZ) observations can be utiliz… ▽ More Galaxy clusters form through hierarchical assembly, where smaller substructures merge to build the largest gravitationally bound objects in the universe. These mergers, combined with feedback from AGN, filamentary accretion, and other energy injection processes, generate turbulence and perturbations within the intra-cluster medium (ICM). X-ray and Sunyaev-Zel'dovich (SZ) observations can be utilized to measure these ICM density and pressure inhomogeneities, in turn providing constraints on the effective Equation of State (EOS) of the perturbations and ICM velocities. In this work, we analyze deep SRG-eROSITA and Planck/SPT observations of Abell 3266 (A3266), a dynamically complex merging cluster with elongated morphology and significant substructure. We measure pressure and density fluctuations, and compute the power spectra and deprojected 3D amplitudes of these perturbations. We estimate the ratio of pressure-to-density fluctuation amplitudes as $1.00 \pm 0.55$ and non-thermal pressure support $0.068 \pm 0.050$. Density fluctuations are found to be stronger in the northern sector of the cluster compared to the south, consistent with ongoing accretion along a filamentary structure revealed by eROSITA. Further, we find the amplitude of density fluctuations increases with radius, qualitatively consistent with the trend found in cosmological simulations. Uncertainties in our results are dominated by the relatively low sensitivity of current Planck/SPT data, suggesting that improvements in SZ data quality could substantially improve our understanding of ICM energy injection, transport, and dissipation from this technique. △ Less

Submitted 24 February, 2026; originally announced February 2026.

Spatially-resolved interstellar dust properties in the face-on spiral galaxy M 99 as observed by NIKA2

Authors: L. Pantoni, F. Galliano, S. C. Madden, R. Adam, P. Ade, H. Ajeddig, P. André, E. Artis, H. Aussel, M. Baes, A. Beelen, A. Benoît, S. Berta, L. Bing, O. Bourrion, M. Calvo, V. Casasola, A. Catalano, I-D. Chang, I. De Looze, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen, G. Ejlali , et al. (40 additional authors not shown)

Abstract: Large dust grains in thermal equilibrium dominate the far-infrared and contribute to the millimetre continuum of star-forming galaxies, but constraining their properties is difficult due to free-free and synchrotron contamination. We study spatial variations in the dust spectral index, mass, and grain properties in the nearby face-on spiral galaxy M 99. We use new 1.15 and 2 mm continuum observati… ▽ More Large dust grains in thermal equilibrium dominate the far-infrared and contribute to the millimetre continuum of star-forming galaxies, but constraining their properties is difficult due to free-free and synchrotron contamination. We study spatial variations in the dust spectral index, mass, and grain properties in the nearby face-on spiral galaxy M 99. We use new 1.15 and 2 mm continuum observations from NIKA2 on the IRAM 30 m telescope (IMEGIN Guaranteed Time Large Programme) combined with multiwavelength data from UV to radio. The infrared-to-radio SED is decomposed into dust, free-free, and synchrotron components using the hierarchical Bayesian code HerBIE. Dust is modelled via a modified blackbody (MBB) with variable millimetre spectral index beta and the THEMIS dust model with fixed beta. We perform spatially-resolved analysis at scales ~1.75 kpc (~25''), covering the centre, spiral arms, and inter-arm regions. MBB fits reveal beta variations from ~1.6-1.7 in diffuse regions to ~2.3-2.5 in dense star-forming areas, likely due to grain coagulation and changes in silicate-to-carbonaceous ratios. Dust masses from variable beta are up to ~4x higher than fixed-beta models, which systematically bias dust-to-stellar and dust-to-gas ratios. The small grain fraction rises from ~10% in the centre to ~15% in the diffuse disc, anti-correlated with the interstellar radiation field; gas-phase metallicity plays a minor role within 8 kpc. Synchrotron spectral index ranges from ~0.6-0.7 in star-forming regions to ~1.2 in the diffuse medium, consistent with cosmic-ray electron ageing. △ Less

Submitted 23 February, 2026; originally announced February 2026.

Comments: 17 pages, 12 figures (26 pages, 29 figures including appendices). Accepted for publication in Astronomy & Astrophysics

Journal ref: A&A 709, A1 (2026)

Resolved ISM properties and scaling relations in the barred galaxy NGC 3627: constraints from NIKA2 observations

Authors: S. Katsioli, E. M. Xilouris, F. Galliano, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, H. Aussel, M. Baes, A. Beelen, A. Benoît, S. Berta, A. Bongiovanni, J. Bounmy, O. Bourrion, M. Calvo, A. Catalano, D. Chérouvrier, I. De Looze, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen, G. Ejlali , et al. (42 additional authors not shown)

Abstract: We investigate the interplay between star formation, interstellar medium (ISM) components, and dust properties in NGC 3627 using new NIKA2 1.15 and 2 mm observations from the IMEGIN Large Program. Our goal is to analyze dust and radio emission, decompose contributions in the millimeter-centimeter regime, and explore ISM properties within the galaxy. We perform spectral energy distribution fitting,… ▽ More We investigate the interplay between star formation, interstellar medium (ISM) components, and dust properties in NGC 3627 using new NIKA2 1.15 and 2 mm observations from the IMEGIN Large Program. Our goal is to analyze dust and radio emission, decompose contributions in the millimeter-centimeter regime, and explore ISM properties within the galaxy. We perform spectral energy distribution fitting, at both global and spatial scales, using the THEMIS dust model within the HerBIE code, applied to data from 3.4 $μ$m to 6 cm. We decompose emission into dust, free-free, and synchrotron components, and examine correlations with gas surface density and star formation activity. Additionally, we analyze the small dust grain fraction and its variation across the galaxy. We find $\sim$10% radio emission at 2 mm, peaking at 18% in the southern bar-end, which hosts the highest star formation activity. However, an isolated star-forming region beyond this bar-end is the most efficient, as indicated by its elevated dust production efficiency and effective yield, predicted by our simplistic dust evolution model. The 160 $μ$m emission shows the strongest correlation with molecular gas, while 1.15 mm better traces the dust mass surface density. Small grains, which make up $\sim$13% of dust mass (2 $\times$ 10$^{7}$ M$_{\odot}$), are depleted in intense radiation fields, with a notable deficit in the southern tidal tail. ISM properties and chemical evolution indicate that dynamical processes, such as bar-driven gas flows and tidal interactions, are crucial in shaping the galactic structure, influencing star formation efficiency, and dust distribution. △ Less

Submitted 13 January, 2026; originally announced January 2026.

Comments: 22 pages, 14 figures, Accepted for publication in MNRAS

CHEX-MATE: Relationship between X-ray and millimetre inferences of galaxy cluster temperature profiles

Authors: F. De Luca, H. Bourdin, P. Mazzotta, G. Luzzi, M. G. Campitiello, M. De Petris, D. Eckert, S. Ettori, A. Ferragamo, W. Forman, M. Gaspari, F. Gastaldello, S. Ghizzardi, M. Gitti, S. T. Kay, J. Kim, L. Lovisari, J. F. Macías-Pérez, B. J. Maughan, M. Muñoz-Echeverría, F. Oppizzi, E. Pointecouteau, G. W. Pratt, E. Rasia, M. Rossetti , et al. (3 additional authors not shown)

Abstract: Thermodynamic profiles from X-ray and millimetre observations of galaxy clusters are often compared under the simplifying assumptions of smooth, spherically symmetric intracluster medium. These approximations lead to expected discrepancies in the inferred profiles, which can provide insights about the cluster structure or cosmology. Motivated by this, we present a joint XMM-\textit{Newton} and \te… ▽ More Thermodynamic profiles from X-ray and millimetre observations of galaxy clusters are often compared under the simplifying assumptions of smooth, spherically symmetric intracluster medium. These approximations lead to expected discrepancies in the inferred profiles, which can provide insights about the cluster structure or cosmology. Motivated by this, we present a joint XMM-\textit{Newton} and \textit{Planck} analysis of 116 CHEX-MATE clusters to measure $η_T = T_X/T_{SZ,X}$, the ratio between spectroscopic X-ray temperatures and a temperature proxy derived from Sunyaev-Zel'dovich (SZ) pressures and X-ray densities. We considered relativistic corrections to the thermal SZ signal and implemented X-ray absorption by Galactic molecular hydrogen. The $η_T$ distribution has a mean of $1.01 \pm 0.03$, with average changes of $8.1\%$ and $2.7\%$ when relativistic corrections and molecular hydrogen absorption are not included, respectively. The $η_T$ distribution is positively skewed, with the scatter mostly affected by cluster morphology: relaxed clusters are closer to unity and less scattered than mixed and disturbed systems. We find little or no correlation with redshift, mass, or temperature. △ Less

Submitted 12 January, 2026; originally announced January 2026.

Comments: Accepted for publication in A&A

NIKA2 Cosmological Legacy Survey. First measurement of the confusion noise at the IRAM 30 m telescope

Authors: N. Ponthieu, F. -X. Désert, A. Beelen, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, H. Aussel, A. Benoît, S. Berta, M. Béthermin, L. J. Bing, A. Bongiovanni, J. Bounmy, O. Bourrion, M. Calvo, A. Catalano, D. Chérouvrier, M. De Petris, S. Doyle, E. F. C. Driessen, G. Ejlali, A. Ferragamo, A. Gomez , et al. (32 additional authors not shown)

Abstract: The NIKA2 Cosmological Legacy Survey (N2CLS) is a large programme using the NIKA2 dual-band camera on the IRAM 30\,m telescope. Its goal is to improve our understanding of the physics of distant Dusty Star Forming Galaxies (DSFGs) by carrying out deep surveys of two fields, GOODS-North and COSMOS. This work is focussed on GOODS-North, which was observed for 78.2 hours, simultaneously at 1.2 and 2\… ▽ More The NIKA2 Cosmological Legacy Survey (N2CLS) is a large programme using the NIKA2 dual-band camera on the IRAM 30\,m telescope. Its goal is to improve our understanding of the physics of distant Dusty Star Forming Galaxies (DSFGs) by carrying out deep surveys of two fields, GOODS-North and COSMOS. This work is focussed on GOODS-North, which was observed for 78.2 hours, simultaneously at 1.2 and 2\,mm, with a field of view of $\sim$240\,arcmin$^2$. With such a deep integration, we were able to measure, for the first time, the confusion noise limits at the 30\,m telescope using the best sampled $\sim 62$\,arcmin$^2$ and masking sources with a flux greater than 0.54 or 0.17\,mJy at 1.2 or 2\,mm, respectively. We found a confusion noise of $139.1^{+ 15.9}_{- 19.2}\pm11.9$\,$μ$Jy/beam at 1.2\,mm and $38.6^{+ 9.6}_{- 13.1} \pm3.7$\,$μ$Jy/beam at 2\,mm (the first uncertainty is statistical, the second is the cosmic variance). In this region, this corresponds to half the instrumental noise. To derive these estimates, we devised a novel estimator, referred to as the cross variance, which also enabled us to estimate the correlated confusion noise between the two bands. Thus, we obtained a result of $49.6^{+ 15.9}_{- 24.8}\pm 6.4$\,$μ$Jy/beam. These values are consistent with the state of the art Simulated Infrared Dusty Extragalactic Sky (SIDES) model. △ Less

Submitted 16 December, 2025; originally announced December 2025.

Comments: 13 pages, 8 figures

Galaxy cluster temperature maps from joint X-ray and SZ maps with The Three Hundred hydrodynamical simulations

Authors: R. Wicker, M. De Petris, A. Ferragamo, I. Bartalucci, G. Yepes, E. Rasia, R. Adam, W. Cui, F. Mayet, L. Perotto, M. Muñoz-Echeverría

Abstract: Galaxy clusters can be used as powerful cosmological probes, provided one can obtain accurate mass estimates, which requires a precise knowledge of the underlying astrophysics of galaxy clusters. For these purposes, spatially resolved measurements of the thermodynamic properties of intra-cluster medium (ICM), such as density and temperature, are necessary. In particular, temperature estimates are… ▽ More Galaxy clusters can be used as powerful cosmological probes, provided one can obtain accurate mass estimates, which requires a precise knowledge of the underlying astrophysics of galaxy clusters. For these purposes, spatially resolved measurements of the thermodynamic properties of intra-cluster medium (ICM), such as density and temperature, are necessary. In particular, temperature estimates are traditionally obtained through spatially resolved X-ray spectroscopy. Such measurements suffer from their sensitivity to the chosen energy calibration, may exhibit inherent biases, and are especially hard to perform at high redshift as they require deep observations. In recent years however, millimetre wavelength data with high spatial resolution, comparable to the one of current X-ray telescopes, have begun to be available. This has enabled the implementation of new methods to infer and map the cluster temperature in individual clusters, using the combination of density maps from X-ray data and pressure maps from millimetre data. In this paper, we present the first systematic validation of this approach on a large sample of synthetic clusters generated in The Three Hundred hydrodynamical simulations. We show that we are able to recover theoretical estimates of the temperature, namely the mass-weighted and spectroscopic-like temperatures, within biases of the order of $\lesssim 1\%$ in the best cases, up to $\sim 10\%$ in average, with scatters of the order of $10\%$. To prepare the application of this approach to observed data, we discuss the modelling of the effective length $l_\mathrm{eff}$, a key quantity necessary for the combination of X-ray and SZ projected data. In particular we provide templates calibrated on simulations for this quantity, and investigate their impact in the recovery of the temperature map, compared to other standard models. △ Less

Submitted 11 November, 2025; originally announced November 2025.

Comments: 13 pages, 12 figures, 2 tables. Submitted to A&A, comments are welcome

Journal ref: A&A 710, A2 (2026)

CHEX-MATE: towards a consistent universal pressure profile and cluster mass reconstruction

Authors: M. Muñoz-Echeverría, E. Pointecouteau, G. W. Pratt, J. -F. Macías-Pérez, M. Douspis, L. Salvati, I. Bartalucci, H. Bourdin, N. Clerc, F. De Luca, M. De Petris, M. Donahue, S. Dupourqué, D. Eckert, S. Ettori, M. Gaspari, F. Gastaldello, M. Gitti, A. Gorce, S. Ilić, S. T. Kay, J. Kim, L. Lovisari, B. J. Maughan, P. Mazzotta , et al. (9 additional authors not shown)

Abstract: In a self-similar paradigm of structure formation, the thermal pressure of the hot intra-cluster gas follows a universal distribution once the profile of each cluster is normalised based on the proper mass and redshift dependencies. The reconstruction of such a universal pressure profile requires an individual estimate of the mass of each cluster. In this context, we present a method to jointly fi… ▽ More In a self-similar paradigm of structure formation, the thermal pressure of the hot intra-cluster gas follows a universal distribution once the profile of each cluster is normalised based on the proper mass and redshift dependencies. The reconstruction of such a universal pressure profile requires an individual estimate of the mass of each cluster. In this context, we present a method to jointly fit, for the first time, the universal pressure profile and individual cluster $M_{500}$ masses over a sample of galaxy clusters, properly accounting for correlations between the profile shape and amplitude, and masses scaling the individual profiles. We demonstrate the power of the method and show that a consistent exploitation of the universal pressure profile and cluster mass estimates when modelling the thermal pressure in clusters is necessary to avoid biases. In particular, the method, informed by a cluster mass scale, outputs individual cluster masses with same accuracy and better precision than input masses. Using data from the «Cluster HEritage project with XMM-Newton: Mass Assembly and Thermodynamics at the Endpoint of structure formation», we investigate a sample of $\sim 25$ galaxy clusters spanning mass and redshift ranges of $2 \lesssim M_{500}/10^{14} \; \mathrm{M}_{\odot} \lesssim 14$ and $0.07 < z < 0.6$. △ Less

Submitted 21 October, 2025; originally announced October 2025.

Comments: Accepted for publication in Astronomy and Astrophysics

Journal ref: A&A 704, A302 (2025)

Thermal Sunyaev-Zel'dovich effect at the core of CL J1226.9+3332 revealed by NOEMA

Authors: M. Muñoz-Echeverría, J. -F. Macías-Pérez, R. Neri, E. Pointecouteau, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, H. Aussel, A. Beelen, A. Benoît, S. Berta, M. Béthermin, A. Bongiovanni, J. Bounmy, O. Bourrion, M. Calvo, A. Catalano, D. Chérouvrier, U. Chowdhury, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen , et al. (36 additional authors not shown)

Abstract: We present first detailed maps of the thermal Sunyaev-Zel'dovich (tSZ) effect on a $z = 0.89$ cluster with the NOrthern Extended Millimeter Array (NOEMA). The high sensitivity of these observations enabled the effective identification and removal of the millimetre-wave sources contaminating the tSZ signal, thus isolating the influence of the hot electron gas of the cluster on the cosmic microwave… ▽ More We present first detailed maps of the thermal Sunyaev-Zel'dovich (tSZ) effect on a $z = 0.89$ cluster with the NOrthern Extended Millimeter Array (NOEMA). The high sensitivity of these observations enabled the effective identification and removal of the millimetre-wave sources contaminating the tSZ signal, thus isolating the influence of the hot electron gas of the cluster on the cosmic microwave background radiation from other emissions. The tSZ observed with success by NOEMA was modelled together with previous single-dish observations (IRAM 30-metre, Green Bank Telescope, and Caltech Sub-millimeter Observatory) to obtain the first core-to-outskirts (from $\sim$ 15 to $\sim$ 1500 kpc) pressure profile reconstruction on such a high-redshift galaxy cluster. NOEMA observations with a high angular resolution have shown that the pressure profile is flat in the core of the cluster. These observations confirm the disturbed nature of CL J1226.9+3332 and map for the first time the distribution of its thermal gas at arcsecond scales in the environments of the central cluster galaxy. Our results showcase the excellent capabilities of NOEMA to complement and enhance the data provided by other millimetre-wave instruments in resolving the core of high-redshift clusters via tSZ emission. △ Less

Submitted 3 November, 2025; v1 submitted 17 September, 2025; originally announced September 2025.

Comments: Updated to match version published in A&A

Journal ref: A&A 702, A275 (2025)

Euclid preparation. Establishing the quality of the 2D reconstruction of the filaments of the cosmic web with DisPerSE using Euclid photometric redshifts

Authors: Euclid Collaboration, N. Malavasi, F. Sarron, U. Kuchner, C. Laigle, K. Kraljic, P. Jablonka, M. Balogh, S. Bardelli, M. Bolzonella, J. Brinchmann, G. De Lucia, F. Fontanot, C. Gouin, M. Hirschmann, Y. Kang, M. Magliocchetti, T. Moutard, J. G. Sorce, M. Spinelli, L. Wang, L. Xie, A. M. C. Le Brun, E. Tsaprazi, O. Cucciati , et al. (291 additional authors not shown)

Abstract: Cosmic filaments are prominent structures of the matter distribution of the Universe. Modern detection algorithms are an efficient way to identify filaments in large-scale observational surveys of galaxies. Many of these methods were originally designed to work with simulations and/or well-sampled spectroscopic surveys. When spectroscopic redshifts are not available, the filaments of the cosmic we… ▽ More Cosmic filaments are prominent structures of the matter distribution of the Universe. Modern detection algorithms are an efficient way to identify filaments in large-scale observational surveys of galaxies. Many of these methods were originally designed to work with simulations and/or well-sampled spectroscopic surveys. When spectroscopic redshifts are not available, the filaments of the cosmic web can be detected in projection using photometric redshifts in slices along the Line of Sight, which enable the exploration of larger cosmic volumes. However, this comes at the expense of a lower redshift precision. It is therefore crucial to assess the differences between filaments extracted from exact redshifts and from photometric redshifts for a specific survey. We apply this analysis to capture the uncertainties and biases of filament extractions introduced by using the photometric sample of the Euclid Wide Survey. The question that we address in this work is how can we compare two filament samples derived with redshifts of different precisions in the Euclid Wide Survey context. We apply the cosmic web detection algorithm DisPerSE, in the redshift range $0.1 \leq z \leq 0.5$, to the GAlaxy Evolution and Assembly (GAEA) simulated galaxy sample which reproduces several characteristics of the Euclid Wide Survey. We develop a method to compare skeletons derived from photometric redshifts to those derived from true galaxy positions. This method expands the commonly used measure of distance between filaments to include geometrical (angles between filaments) and astrophysical considerations (galaxy mass gradients and connectivity-mass relations). We assess whether this approach strengthens our ability to correctly identify filaments in very large surveys such as the Euclid Wide Survey. [abridged] △ Less

Submitted 21 August, 2025; originally announced August 2025.

Comments: 27 pages, 14 Figures

The NIKA2 cosmological legacy survey at 2 mm: catalogs, colors, redshift distributions, and implications for deep surveys

Authors: M. Béthermin, G. Lagache, C. Carvajal-Bohorquez, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, H. Aussel, A. Beelen, A. Benoît, S. Berta, L. J. Bing, A. Bongiovanni, J. Bounmy, O. Bourrion, M. Calvo, A. Catalano, D. Chérouvrier, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen, G. Ejlali, A. Ferragamo , et al. (32 additional authors not shown)

Abstract: Millimeter galaxy surveys are particularly effective in detecting dusty star-forming galaxies at high redshift. While such observations are typically conducted at ~1mm, some studies suggest that 2mm may be better suited for selecting sources at even higher redshifts. We use the unprecedented 2mm data from the N2CLS, together with the SIDES simulation, to study and interpret the statistical propert… ▽ More Millimeter galaxy surveys are particularly effective in detecting dusty star-forming galaxies at high redshift. While such observations are typically conducted at ~1mm, some studies suggest that 2mm may be better suited for selecting sources at even higher redshifts. We use the unprecedented 2mm data from the N2CLS, together with the SIDES simulation, to study and interpret the statistical properties of 2mm-selected galaxies. We use the N2CLS robust sample at 2mm, which contains 25 sources in the deep GOODS-N field and 90 sources in the wide COSMOS. The sources are matched with the N2CLS 1.2mm sources, the ancillary 850um sources, and redshift catalogs to study the colors and redshift distributions. We also produce end-to-end simulations based on SIDES and the observed N2CLS detector timelines to interpret the data. We find a mean S2/S1.2 color of 0.222$\pm$0.008 with a standard deviation of 0.070$\pm$0.010. We measure a mean redshift of $3.6\pm0.3$ in GOODS-N, which is marginally higher than expectations from SIDES ($2.9\pm0.2$) because of an overdensity at $z\sim5.2$, and $3.2\pm0.2$ in COSMOS, which agrees with the $3.2\pm0.2$ predicted by SIDES. We also show that the observed S2/S1.2 colors exhibit a weak dependence with redshift but a large dispersion, which limits its efficiency to select high-z sources. Finally, we studied the nine 2mm sources not detected at 1.2mm, and found that two of them are radiogalaxies, one is a z~2 galaxy, and the remaining six are compatible with the expected number of spurious detections. The N2CLS survey shows no evidence for any exotic 2mm-only galaxy population. Using SIDES, we show that 2mm samples have a higher mean redshift compared to 1.2mm because they miss z~2 dusty galaxies. Finally, we discuss the efficiency of single-dish and interferometric blind surveys to build samples of high-z dusty galaxies. △ Less

Submitted 28 January, 2026; v1 submitted 27 June, 2025; originally announced June 2025.

Comments: 16 pages, 8 figures, submitted to A&A, data are available at https://data.lam.fr/n2cls/

Journal ref: A&A 708, A295 (2026)

NIKA2 Cosmological Legacy Survey: Blind detection of galaxy clusters in the COSMOS field via the Sunyaev-Zel'dovich effect

Authors: D. Chérouvrier, J. F. Macias-Perez, F. X. Désert, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, H. Aussel, R. Barrena, A. Beelen, A. Benoit, S. Berta, M. Béthermin, A. Bongiovanni, J. Bounmy, O. Bourrion, L. -J. Bing, M. Calvo, A. Catalano, M. De Petris, S. Doyle, E. F. C. Driessen, G. Ejlali, A. Ferragamo , et al. (37 additional authors not shown)

Abstract: (Abridged) Clusters of galaxies, formed in the latest stages of structure formation, are unique cosmological probes. With the advent of large CMB surveys like those from the Planck satellite, the ACT and SPT telescopes, we now have access to a large number of galaxy clusters detected at millimeter wavelengths via the thermal Sunyaev-Zel'dovich (tSZ) effect. Nevertheless, it is interesting to compl… ▽ More (Abridged) Clusters of galaxies, formed in the latest stages of structure formation, are unique cosmological probes. With the advent of large CMB surveys like those from the Planck satellite, the ACT and SPT telescopes, we now have access to a large number of galaxy clusters detected at millimeter wavelengths via the thermal Sunyaev-Zel'dovich (tSZ) effect. Nevertheless, it is interesting to complement them with high-angular-resolution (tens of arcseconds) observations to target the lowest-mass and highest-redshift clusters. This is the case of observations with the NIKA2 camera, which is installed on the IRAM 30--m telescope in Pico Veleta, Spain. We used the existing 150 GHz (2 mm) data from the NIKA2 Cosmological Legacy Survey (N2CLS) Large Program to blindly search for galaxy clusters in the well-known COSMOS field, across a 877 arcmin$^2$ region centered on (R.A., Dec.)$_{J2000}$ = (10h00m28.81s, +02d17m30.44s). We first developed a dedicated data reduction pipeline to construct NIKA2 maps at 2 mm. We then used a matched-filter algorithm to extract cluster candidates assuming a universal pressure profile to model the expected cluster tSZ signal. We computed the purity and completeness of the sample by applying the previous algorithm to simulated maps of the sky signal in the COSMOS field. We find a total of 16 cluster candidates at S/N > 4, from which eight have either an optical or X-ray cluster (or group of galaxies) counterpart. This is the first blind detection of clusters of galaxies at mm wavelengths at 18" angular resolution. From this analysis, we confirm that NIKA2 and the IRAM 30--m telescope should be sensitive to low-mass clusters at intermediate and high redshift, complementing current and planned large tSZ-based cluster surveys. △ Less

Submitted 22 June, 2025; originally announced June 2025.

Overdense fireworks in GOODS-N: Unveiling a record number of massive dusty star forming galaxies at z$\sim$5.2 with the N2CLS

Authors: G. Lagache, M. Xiao, A. Beelen, S. Berta, L. Ciesla, R. Neri, R. Pello, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, H. Aussel, A. Benoît, M. Béthermin, L. -J. Bing, A. Bongiovanni, J. Bounmy, O. Bourrion, M. Calvo, A. Catalano, D. Chérouvrier, U. Chowdhury, M. De Petris, F. -X. Désert , et al. (37 additional authors not shown)

Abstract: As part of the N2CLS Survey, we have identified a remarkable overdensity of eight bright dusty star-forming galaxies at z$\sim$5.2 in the GOODS-N field. Three of these galaxies, N2GN_1_01, 06, and 23 (known as GN10, HDF850.1, and S3, respectively), had previously been spectroscopically confirmed as members of the exceptional large-scale structure at z$\sim$5.1-5.3, which is notably elongated along… ▽ More As part of the N2CLS Survey, we have identified a remarkable overdensity of eight bright dusty star-forming galaxies at z$\sim$5.2 in the GOODS-N field. Three of these galaxies, N2GN_1_01, 06, and 23 (known as GN10, HDF850.1, and S3, respectively), had previously been spectroscopically confirmed as members of the exceptional large-scale structure at z$\sim$5.1-5.3, which is notably elongated along the line of sight, spanning 30 cMpc. We present the spectroscopic confirmation of N2GN_1_13 at z$_{\rm spec}$=5.182, a massive dusty star-forming galaxy identified through targeted NOEMA observations, and N2GN_1_61 at z$_{\rm spec}$=5.201, revealed using JWST/FRESCO data. In addition to these five spectroscopically confirmed members, we identify three further candidates with photometric redshifts consistent with the overdense structure. These galaxies are massive (with a median stellar mass of 9x 10$^{10}$ M$_{\odot}$) and highly obscured (with a median A$_V$ of 3.3), caught in a short-lived yet extreme starburst phase at z$\sim$5.2. Their high SFRs (with a median of 590 M$_{\odot}$ yr$^{-1}$), efficient baryon to stellar mass conversion ($ε_{\star}>$20%), substantial gas reservoir and dust content, suggest rapid evolution and imminent quenching. Six of these galaxies reside in overdense filaments; the remaining two may trace new distinct structures which will have to be spectroscopically confirmed. These few dusty galaxies dominate the star formation within the overdensity, contributing more than the numerous H$_α$ emitters, and surpassing the cosmic average star formation rate density for this epoch. Their properties suggest an accelerated evolution that current models and simulations have difficulty reproducing. △ Less

Submitted 14 December, 2025; v1 submitted 18 June, 2025; originally announced June 2025.

Comments: Match final A&A version

Journal ref: A&A 705, A214 (2026)

The Three Hundred Project: Modeling Baryon and Hot-Gas Fraction Evolution in Simulated Clusters

Authors: Elena Rasia, Roberta Tripodi, Stefano Borgani, Veronica Biffi, Camille Avestruz, Weiguang Cui, Marco De Petris, Klaus Dolag, Dominique Eckert, Stefano Ettori, Massimo Gaspari

Abstract: The baryon fraction of galaxy clusters is a powerful tool to inform on the cosmological parameters while the hot-gas fraction provides indications on the physics of the intracluster plasma and its interplay with the processes driving galaxy formation. Using cosmological hydrodynamical simulations from The Three Hundred collaboration of about 300 simulated massive galaxy clusters with median mass… ▽ More The baryon fraction of galaxy clusters is a powerful tool to inform on the cosmological parameters while the hot-gas fraction provides indications on the physics of the intracluster plasma and its interplay with the processes driving galaxy formation. Using cosmological hydrodynamical simulations from The Three Hundred collaboration of about 300 simulated massive galaxy clusters with median mass $M_{500}\approx7 \times 10^{14}$M$_{\odot}$ at $z=0$, we model the relations between total mass and either baryon fraction or the hot gas fractions at overdensities $Δ= 2500$, $500$, and $200$ with respect to the cosmic critical density, and their evolution from $z\sim 0$ to $z\sim 1.3$. We fit the simulation results for such scaling relations against three analytic forms (linear, quadratic, and logarithmic in a logarithmic plane) and three forms for the redshift dependence, considering as a variable both the inverse of cosmic scale factor, $(1+z)$, and the Hubble expansion rate, $E(z)$. We show that power-law dependencies on cluster mass poorly describe the investigated relations. A power-law fails to simultaneously capture the flattening of the total baryon and gas fractions at high masses, their drop at the low masses, and the transition between these two regimes. The other two functional forms provide a more accurate description of the curvature in mass scaling. The fractions measured within smaller radii exhibit a stronger evolution than those measured within larger radii. From the analysis of these simulations, we conclude that as long as we include systems in the mass range herein investigated, the baryon or gas fraction can be accurately related to the total mass through either a parabola or a logarithm in the logarithmic plane. The trends are common to all modern hydro simulations, although the amplitude of the drop at low masses might differ [Abridged]. △ Less

Submitted 27 May, 2025; originally announced May 2025.

Comments: Resubmitted to Astronomy and Astrophysics after the first referee report

Journal ref: A&A 702, A182 (2025)

Continuum, CO and Water vapour maps of the Orion Nebula. First millimetre spectral imaging with Concerto

Authors: F. -X. Désert, J. F. Macías-Pérez, A. Beelen, A. Benoît, M. Béthermin, J. Bounmy, O. Bourrion, M. Calvo, A. Catalano, C. De Breuck, C. Dubois, C. A Durán, A. Fasano, J. Goupy, W. Hu, E. Ibar, G. Lagache, A. Lundgren, A. Monfardini, N. Ponthieu, D. Quinatoa, M. Van Cuyck, R. Adam, P. Ade, H. Ajeddig , et al. (38 additional authors not shown)

Abstract: The millimetre spectrum of Galactic regions and galaxies is rich in continuum and molecular lines. This diversity is mostly explored using either broad-band photometry or high-resolution heterodyne spectroscopy. We aim to map the millimetre continuum emission of Galactic regions with an intermediate spectral resolution between broad-band photometry and heterodyne spectroscopy, enabling us to rapid… ▽ More The millimetre spectrum of Galactic regions and galaxies is rich in continuum and molecular lines. This diversity is mostly explored using either broad-band photometry or high-resolution heterodyne spectroscopy. We aim to map the millimetre continuum emission of Galactic regions with an intermediate spectral resolution between broad-band photometry and heterodyne spectroscopy, enabling us to rapidly cover large sky areas with spectroscopy. We report observations of the Orion Nebula with the CONCERTO instrument, which was installed at the APEX telescope focal plane from 2021 to 2023. We find that the spectrum of Orion is dominated by dust emission with an emissivity index ranging between 1.3 and 2.0, along with strong CO(2-1) and H$_2$O lines, which are naturally separated from the continuum due to the CONCERTO spectral capabilities. Many regions also show strong free-free emission at lower frequencies. We demonstrate the spectral capabilities of CONCERTO at intermediate spectral resolution, with a frequency coverage from 130 to 310 GHz. A sensitivity of 200 mK is achieved in one second, for one beam and a 6 GHz frequency width, over an 18 arcmin diameter field of view, which is within a factor of three of the expectations. We show that we can spectrally disentangle the continuum from the CO line emission, but the line is not resolved at a resolution of $\sim 8000\ \mathrm{km s^{-1}}$. The slope of the millimetre continuum is line-free mapped for the first time in Orion. △ Less

Submitted 19 September, 2025; v1 submitted 29 April, 2025; originally announced April 2025.

Comments: 12 pages, 12 figures, 2 tables, matching the Astron. & Astrophys published version

Journal ref: A&A 701, A210 (2025)

LiteBIRD Science Goals and Forecasts: constraining isotropic cosmic birefringence

Authors: E. de la Hoz, P. Diego-Palazuelos, J. Errard, A. Gruppuso, B. Jost, R. M. Sullivan, M. Bortolami, Y. Chinone, L. T. Hergt, E. Komatsu, Y. Minami, I. Obata, D. Paoletti, D. Scott, P. Vielva, D. Adak, R. Akizawa, A. Anand, J. Aumont, C. Baccigalupi, A. J. Banday, R. B. Barreiro, N. Bartolo, S. Basak, A. Basyrov , et al. (90 additional authors not shown)

Abstract: Cosmic birefringence (CB) is the rotation of the photons' linear polarisation plane during propagation. Such an effect is a tracer of parity-violating extensions of standard electromagnetism and would probe the existence of a new cosmological field acting as dark matter or dark energy. It has become customary to employ cosmic microwave background (CMB) polarised data to probe such a phenomenon. Re… ▽ More Cosmic birefringence (CB) is the rotation of the photons' linear polarisation plane during propagation. Such an effect is a tracer of parity-violating extensions of standard electromagnetism and would probe the existence of a new cosmological field acting as dark matter or dark energy. It has become customary to employ cosmic microwave background (CMB) polarised data to probe such a phenomenon. Recent analyses on Planck and WMAP data provide a hint of detection of the isotropic CB angle with an amplitude of around $0.3^\circ$ at the level of $2.4$ to $3.6σ$. In this work, we explore the LiteBIRD capabilities in constraining such an effect, accounting for the impact of the more relevant systematic effects, namely foreground emission and instrumental polarisation angles. We build five semi-independent pipelines and test these against four different simulation sets with increasing complexity in terms of non-idealities. All the pipelines are shown to be robust and capable of returning the expected values of the CB angle within statistical fluctuations for all the cases considered. We find that the uncertainties in the CB estimates increase with more complex simulations. However, the trend is less pronounced for pipelines that account for the instrumental polarisation angles. For the most complex case analysed, we find that LiteBIRD will be able to detect a CB angle of $0.3^\circ$ with a statistical significance ranging from $5$ to $13 \, σ$, depending on the pipeline employed, where the latter uncertainty corresponds to a total error budget of the order of $0.02^\circ$. △ Less

Submitted 23 June, 2025; v1 submitted 28 March, 2025; originally announced March 2025.

Comments: 56 pages, 22 figures. Accepted for publication in JCAP

The impact of baryons on the sparsity of simulated galaxy clusters from The Three Hundred Project

Authors: P. S. Corasaniti, T. R. G. Richardson, S. Ettori, M. De Petris, E. Rasia, W. Cui, G. Yepes, G. Gianfagna, A. M. C. Le Bun, Y. Rasera

Abstract: Measurements of the sparsity of galaxy clusters can be used to probe the cosmological information encoded in the host dark matter halo profile, and infer constraints on the cosmological model parameters. Key to the success of these analyses is the control of potential sources of systematic uncertainty. As an example, the presence of baryons can alter the cluster sparsity with respect to prediction… ▽ More Measurements of the sparsity of galaxy clusters can be used to probe the cosmological information encoded in the host dark matter halo profile, and infer constraints on the cosmological model parameters. Key to the success of these analyses is the control of potential sources of systematic uncertainty. As an example, the presence of baryons can alter the cluster sparsity with respect to predictions from N-body simulations. Similarly, a radial dependent mass bias, as in the case of masses inferred under the hydrostatic equilibrium (HE) hypothesis, can affect sparsity estimates. We examine the imprint of baryonic processes on the sparsity statistics. Then, we investigate the relation between cluster sparsities and gas mass fraction. Finally, we perform a study of the impact of HE mass bias on sparsity measurements and the implication on cosmological parameter inference analyses. We use catalogues of simulated galaxy clusters from The Three Hundred project and run a comparative analysis of the sparsity of clusters from N-body/hydro simulations implementing different feedback model scenarios. Sparsities which probe the mass profile across a large radial range are affected by the presence of baryons in a way that is particularly sensitive to astrophysical feedback, whereas those probing exclusively external cluster regions are less affected. In the former case, we find the sparsities to be moderately correlated with measurements of the gas fraction in the inner cluster regions. We infer constraints on $S_8$ using synthetic average sparsity measurements generated to evaluate the impact of baryons, selection effects and HE bias. In the case of multiple sparsities these lead to highly bias results. Hence, we calibrate linear bias models that enable us to correct for these effects and recover unbiased constraints that are significantly tighter than those inferred from single sparsity analyses. △ Less

Submitted 21 March, 2025; v1 submitted 20 March, 2025; originally announced March 2025.

Comments: 23 pages, 29 figures, accepted in A&A

Journal ref: A&A 697, A33 (2025)

A panchromatic view of N2CLS GOODS-N: the evolution of the dust cosmic density since z~7

Authors: S. Berta, G. Lagache, A. Beelen, R. Adam, P. Ade, H. Ajeddig, S. Amarantidis, P. André, H. Aussel, A. Benoît, M. Bethermin, L. -J. Bing, A. Bongiovanni, J. Bounmy, O. Bourrion, M. Calvo, A. Catalano, D. Chérouvrier, L. Ciesla, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen, G. Ejlali, D. Elbaz , et al. (36 additional authors not shown)

Abstract: (abridged) To understand early star formation, it is essential to determine the dust mass budget of high-redshift galaxies. Sub-millimeter rest-frame emission, dominated by cold dust, is an unbiased tracer of dust mass. The NIKA2 camera conducted a deep blank field survey at 1.2 and 2.0 mm in the GOODS-N field as part of the NIKA2 Cosmological Legacy Survey (N2CLS), detecting 65 sources with SNR>=… ▽ More (abridged) To understand early star formation, it is essential to determine the dust mass budget of high-redshift galaxies. Sub-millimeter rest-frame emission, dominated by cold dust, is an unbiased tracer of dust mass. The NIKA2 camera conducted a deep blank field survey at 1.2 and 2.0 mm in the GOODS-N field as part of the NIKA2 Cosmological Legacy Survey (N2CLS), detecting 65 sources with SNR>=4.2. Thanks to a dedicated interferometric program with NOEMA and other high-angular resolution data, we identify the multi-wavelength counterparts of these sources and resolve them into 71 individual galaxies. We build detailed SEDs and assign a redshift to 68 of them, over the range 0.6<z<7.2. We fit these SEDs using MBB and Draine & Li (2007) models, and the panchromatic approaches MAGPHYS, CIGALE, and SED3FIT, thus deriving their dust mass, M(dust), infrared luminosity (LIR), and stellar mass, M(star). Eight galaxies require an AGN-torus component and other six require an unextinguished young stellar population. A significant fraction of our galaxies are classified as starbursts based on their position on the M(star) versus SFR plane or their depletion timescales. We compute the dust mass function in three redshift bins (1.6<z<=2.4, 2.4<z<=4.2 and 4.2<z<=7.2) and determine the Schechter function that best describes it. We observe an increase of the dust cosmic density, rho(dust), by at least an order of magnitude from z~7 to z~1.5, consistent with theoretical predictions. At lower redshift the evolution flattens; significant differences exist between results obtained with different selections and methods. The superb GOODS-N dataset enabled a systematic investigation into the dust properties of distant galaxies. N2CLS holds promise for combining these deep field findings with the wide COSMOS field into a self-consistent analysis of dust in galaxies both near and far. △ Less

Submitted 10 March, 2025; originally announced March 2025.

Comments: Accepted for publication on A&A; 48 pages, 22 figures

Euclid preparation: TBD. The impact of line-of-sight projections on the covariance between galaxy cluster multi-wavelength observable properties -- insights from hydrodynamic simulations

Authors: Euclid Collaboration, A. Ragagnin, A. Saro, S. Andreon, A. Biviano, K. Dolag, S. Ettori, C. Giocoli, A. M. C. Le Brun, G. A. Mamon, B. J. Maughan, M. Meneghetti, L. Moscardini, F. Pacaud, G. W. Pratt, M. Sereno, S. Borgani, F. Calura, G. Castignani, M. De Petris, D. Eckert, G. F. Lesci, J. Macias-Perez, M. Maturi, A. Amara , et al. (218 additional authors not shown)

Abstract: Cluster cosmology can benefit from combining multi-wavelength studies, which can benefit from characterising the correlation coefficients between different mass-observable relations. In this work, we aim to provide information on the scatter, the skewness, and the covariance of various mass-observable relations in galaxy clusters in cosmological hydrodynamic simulations. This information will help… ▽ More Cluster cosmology can benefit from combining multi-wavelength studies, which can benefit from characterising the correlation coefficients between different mass-observable relations. In this work, we aim to provide information on the scatter, the skewness, and the covariance of various mass-observable relations in galaxy clusters in cosmological hydrodynamic simulations. This information will help future analyses to better tackle accretion histories and projection effects and model mass observable relations for cosmology studies.We identify galaxy clusters in Magneticum Box2b simulations with mass $M_{\rm 200c}>10^{14} {\rm M}_\odot$ at redshift $z=0.24$ and $z=0.90$. Our analysis includes \Euclid-derived properties such as richness, stellar mass, lensing mass, and concentration. Additionally, we investigate complementary multi-wavelength data, including X-ray luminosity, integrated Compton-$y$ parameter, gas mass, and temperature. The impact of projection effects on mass-observable residuals and correlations is then examined. At intermediate redshift ($z=0.24$), projection effects impact lensing concentration, richness, and gas mass the most in terms of scatter and skewness of log-residuals of scaling relations. The contribution of projection effects can be significant enough to boost a spurious hot- vs. cold-baryons correlation and consequently hide underlying correlations due to halo accretion histories. At high redshift ($z=0.9$), the richness has a much lower scatter (of log-residuals), and the quantity that is most impacted by projection effects is the lensing mass. Lensing concentration reconstruction, in particular, is affected by deviations of the reduced-shear profile shape from the one derived by an NFW profile rather than interlopers in the line of sight. △ Less

Submitted 29 November, 2024; originally announced December 2024.

Comments: 26 pages, 22 figures, submitted to A&A, replied to referee comments

Journal ref: A&A 695, A282 (2025)

The Atacama Cosmology Telescope: A census of bridges between galaxy clusters

Authors: G. Isopi, V. Capalbo, A. D. Hincks, L. Di Mascolo, E. Barbavara, E. S. Battistelli, J. R. Bond, W. Cui, W. R. Coulton, M. De Petris, M. Devlin, K. Dolag, J. Dunkley, D. Fabjan, A. Ferragamo, A. S. Gill, Y. Guan, M. Halpern, M. Hilton, J. P. Hughes, M. Lokken, J. van Marrewijk, K. Moodley, T. Mroczkowski, J. Orlowski-Scherer , et al. (5 additional authors not shown)

Abstract: According to CMB measurements, baryonic matter constitutes about $5\%$ of the mass-energy density of the universe. A significant population of these baryons, for a long time referred to as `missing', resides in a low density, warm-hot intergalactic medium (WHIM) outside galaxy clusters, tracing the ``cosmic web'', a network of large scale dark matter filaments. Various studies have detected this i… ▽ More According to CMB measurements, baryonic matter constitutes about $5\%$ of the mass-energy density of the universe. A significant population of these baryons, for a long time referred to as `missing', resides in a low density, warm-hot intergalactic medium (WHIM) outside galaxy clusters, tracing the ``cosmic web'', a network of large scale dark matter filaments. Various studies have detected this inter-cluster gas, both by stacking and by observing individual filaments in compact, massive systems. In this paper, we study short filaments (< 10 Mpc) connecting massive clusters ($M_{500} \approx 3\times 10^{14} M_{\odot}$) detected by the Atacama Cosmology Telescope (ACT) using the scattering of CMB light off the ionised gas, a phenomenon known as the thermal Sunyaev-Zeldovich (tSZ) effect. The first part of this work is a search for suitable candidates for high resolution follow-up tSZ observations. We identify four cluster pairs with an intercluster signal above the noise floor (S/N $>$ 2), including two with a tentative $>2σ$ statistical significance for an intercluster bridge from the ACT data alone. In the second part of this work, starting from the same cluster sample, we directly stack on ${\sim}100$ cluster pairs and observe an excess SZ signal between the stacked clusters of $y=(7.2^{+2.3}_{-2.5})\times 10^{-7}$ with a significance of $3.3σ$. It is the first tSZ measurement of hot gas between clusters in this range of masses at moderate redshift ($\langle z\rangle\approx 0.5$). We compare this to the signal from simulated cluster pairs with similar redshifts and separations in the THE300 and MAGNETICUM Pathfinder cosmological simulations and find broad consistency. Additionally, we show that our measurement is consistent with scaling relations between filament parameters and mass of the embedded halos identified in simulations. △ Less

Submitted 27 June, 2025; v1 submitted 18 October, 2024; originally announced October 2024.

Comments: 37 pages, 17 images

MSC Class: 85A40 (Primary)

Inference of morphology and dynamical state of nearby $Planck$-SZ galaxy clusters with Zernike polynomials

Authors: Valentina Capalbo, Marco De Petris, Antonio Ferragamo, Weiguang Cui, Florian Ruppin, Gustavo Yepes

Abstract: We analyse the maps of the Sunyaev-Zel'dovich (SZ) signal of local galaxy clusters ($z<0.1$) observed by the $Planck$ satellite in order to classify their dynamical state through morphological features. To study the morphology of the cluster maps, we apply a method recently employed on mock SZ images generated from hydrodynamical simulated galaxy clusters in THE THREE HUNDRED (THE300) project. Her… ▽ More We analyse the maps of the Sunyaev-Zel'dovich (SZ) signal of local galaxy clusters ($z<0.1$) observed by the $Planck$ satellite in order to classify their dynamical state through morphological features. To study the morphology of the cluster maps, we apply a method recently employed on mock SZ images generated from hydrodynamical simulated galaxy clusters in THE THREE HUNDRED (THE300) project. Here, we report the first application on real data. The method consists in modelling the images with a set of orthogonal functions defined on circular apertures, the Zernike polynomials. From the fit we compute a single parameter, $\mathcal{C}$, that quantifies the morphological features present in each image. The link between the morphology of 2D images and the dynamical state of the galaxy clusters is well known, even if not obvious. We use mock $Planck$-like Compton parameter maps generated for THE300 clusters to validate our morphological analysis. These clusters, in fact, are properly classified for their dynamical state with the relaxation parameter, $χ$, by exploiting 3D information from simulations. We find a mild linear correlation of $\sim 38\%$ between $\mathcal{C}$ and $χ$ for THE300 clusters, mainly affected by the noise present in the maps. In order to obtain a proper dynamical-state classification for the $Planck$ clusters, we exploit the conversion from the $\mathcal{C}$ parameter derived in each $Planck$ map in $χ$. A fraction of the order of $63\%$ of relaxed clusters is estimated in the selected $Planck$ sample. Our classification is then compared with those of previous works that have attempted to evaluate, with different indicators and/or other wavelengths, the dynamical state of the same $Planck$ objects. The agreement with the other works is larger than $58\%$. △ Less

Submitted 14 April, 2025; v1 submitted 17 October, 2024; originally announced October 2024.

Comments: 14 pages, 7 figures, 2 tables, Appendix A. Accepted for publication in A&A. Reproduced with permission from Astronomy & Astrophysics, copyright ESO

Journal ref: A&A 698, A201 (2025)

Exploiting the high-resolution NIKA2 data to study the intracluster medium and dynamical state of ACT-CL J0240.0+0116

Authors: A. Paliwal, M. De Petris, A. Ferragamo, R. Adam, P. Ade, H. Ajeddig, P. André, E. Artis, H. Aussel, I. Bartalucci, A. Beelen, A. Benoît, S. Berta, L. Bing, O. Bourrion, M. Calvo, A. Catalano, F. De Luca, F. -X. Désert, S. Doyle, E. F. C. Driessen, G. Ejlali, A. Gomez, J. Goupy, C. Hanser , et al. (32 additional authors not shown)

Abstract: Having a detailed knowledge of the intracluster medium (ICM) to infer the exact cluster physics such as the cluster dynamical state is crucial for cluster-based cosmological studies. This knowledge limits the accuracy and precision of mass estimation, a key parameter for such studies. In this paper, we conduct an in-depth analysis of cluster ACT-CL J0240.0+0116 using a multi-wavelength approach, w… ▽ More Having a detailed knowledge of the intracluster medium (ICM) to infer the exact cluster physics such as the cluster dynamical state is crucial for cluster-based cosmological studies. This knowledge limits the accuracy and precision of mass estimation, a key parameter for such studies. In this paper, we conduct an in-depth analysis of cluster ACT-CL J0240.0+0116 using a multi-wavelength approach, with a primary focus on high angular resolution Sunyaev-Zeldovich (SZ) thermal component observations obtained under the NIKA2 Sunyaev-Zeldovich Large Programme (LPSZ). We create composite images using NIKA2, X-ray, and optical galaxy number density maps. The results reveal distinct signs of disturbance within the cluster with the distributions of gas and member galaxies that do not overlap. We also find suggestions of an inflow of matter onto the cluster from the southwestern direction. Ultimately, we classify the cluster as disturbed, using morphological indicators derived from its SZ, X-ray, and optical image. The cluster SZ signal is also contaminated by a strong central point source. We adopt different approaches to handling this contaminant and find the estimates of our pressure and hydrostatic mass profiles robust to the point source mitigation model. The cluster hydrostatic mass is estimated at $4.25^{+0.50}_{-0.45\, } \times 10^{14} \,\mathrm{M}_{\odot}$ for the case where the point source was masked. These values are consistent with the mass estimated using only X-ray data and with those from previous SZ studies of the Atacama cosmology telescope (ACT) survey, with improved precision on the mass estimate. Our findings strongly suggest that ACT-CL J0240.0+0116 is a disturbed cluster system, and the detailed observations and derived values serve as a compelling case study for the capabilities of the LPSZ in mapping the cluster ICM with high precision. △ Less

Submitted 15 October, 2024; originally announced October 2024.

Comments: 13 pages, 7 figures, submitted to A&A

Journal ref: A&A 698, A2 (2025)

Interpreting Millimeter Emission from IMEGIN galaxies NGC 2146 and NGC 2976

Authors: G. Ejlali, F. S. Tabatabaei, H. Roussel, R. Adam, P. Ade, H. Ajeddig, P. André, E. Artis, H. Aussel, M. Baes, A. Beelen, A. Benoît, S. Berta, L. Bing, O. Bourrion, M. Calvo, A. Catalano, I. De Looze, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen, F. Galliano, A. Gomez, J. Goupy , et al. (37 additional authors not shown)

Abstract: The millimeter continuum emission from galaxies provides important information about cold dust, its distribution, heating, and role in their InterStellar Medium (ISM). This emission also carries an unknown portion of the free-free and synchrotron radiation. The IRAM 30m Guaranteed Time Large Project, Interpreting Millimeter Emission of Galaxies with IRAM and NIKA2 (IMEGIN) provides a unique opport… ▽ More The millimeter continuum emission from galaxies provides important information about cold dust, its distribution, heating, and role in their InterStellar Medium (ISM). This emission also carries an unknown portion of the free-free and synchrotron radiation. The IRAM 30m Guaranteed Time Large Project, Interpreting Millimeter Emission of Galaxies with IRAM and NIKA2 (IMEGIN) provides a unique opportunity to study the origin of the millimeter emission on angular resolutions of <18" in a sample of nearby galaxies. As a pilot study, we present millimeter observations of two IMEGIN galaxies, NGC 2146 (starburst) and NGC 2976 (peculiar dwarf) at 1.15 mm and 2 mm. Combined with the data taken with Spitzer, Herschel, Plank, WSRT, and the 100m Effelsberg telescopes, we model the infrared-to-radio Spectral Energy Distribution (SED) of these galaxies, both globally and at resolved scales, using a Bayesian approach to 1) dissect different components of the millimeter emission, 2) investigate the physical properties of dust, and 3) explore correlations between millimeter emission, gas, and Star Formation Rate (SFR). We find that cold dust is responsible for most of the 1.15 mm emission in both galaxies and at 2 mm in NGC 2976. The free-free emission emits more importantly in NGC 2146 at 2 mm. The cold dust emissivity index is flatter in the dwarf galaxy ($β= 1.3\pm 0.1$) compared to the starburst galaxy ($β= 1.7\pm 0.1$). Mapping the dust-to-gas ratio, we find that it changes between 0.004 and 0.01 with a mean of $0.006\pm0.001$ in the dwarf galaxy. In addition, no global balance holds between the formation and dissociation of H$_2$ in this galaxy. We find tight correlations between the millimeter emission and both the SFR and molecular gas mass in both galaxies. △ Less

Submitted 13 October, 2024; originally announced October 2024.

Comments: Accepted for publication in Astronomy & Astrophysics

Journal ref: A&A 693, A88 (2025)

Deep Learning generated observations of galaxy clusters from dark-matter-only simulations

Authors: Andrés Caro, Daniel de Andres, Weiguang Cui, Gustavo Yepes, Marco De Petris, Antonio Ferragamo, Félicien Schiltz, Amélie Nef

Abstract: Hydrodynamical simulations play a fundamental role in modern cosmological research, serving as a crucial bridge between theoretical predictions and observational data. However, due to their computational intensity, these simulations are currently constrained to relatively small volumes. Therefore, this study investigates the feasibility of utilising dark matter-only simulations to generate observa… ▽ More Hydrodynamical simulations play a fundamental role in modern cosmological research, serving as a crucial bridge between theoretical predictions and observational data. However, due to their computational intensity, these simulations are currently constrained to relatively small volumes. Therefore, this study investigates the feasibility of utilising dark matter-only simulations to generate observable maps of galaxy clusters using a deep learning approach based on the U-Net architecture. We focus on reconstructing Compton-y parameter maps (SZ maps) and bolometric X-ray surface brightness maps (X-ray maps) from total mass density maps. We leverage data from \textsc{The Three Hundred} simulations, selecting galaxy clusters ranging in mass from $10^{13.5} h^{-1}M_{\odot}\leq M_{200} \leq 10^{15.5} h^{-1}M_{\odot}$. Despite the machine learning models being independent of baryonic matter assumptions, a notable limitation is their dependency on the underlying physics of hydrodynamical simulations. To evaluate the reliability of our generated observable maps, we employ various metrics and compare the observable-mass scaling relations. For clusters with masses greater than $2 \times 10^{14} h^{-1} M_{\odot}$, the predictions show excellent agreement with the ground-truth datasets, with percentage errors averaging (0.5 $\pm$ 0.1)\% for the parameters of the scaling laws. △ Less

Submitted 11 March, 2025; v1 submitted 5 October, 2024; originally announced October 2024.

Comments: 16 pages, 13 Figures. Accepted in RASTI

KISS: instrument description and performance

Authors: J. F. Macías-Pérez, M. Fernández-Torreiro, A. Catalano, A. Fasano, M. Aguiar, A. Beelen, A. Benoit, A. Bideaud, J. Bounmy, O. Bourrion, M. Calvo, J. A. Castro-Almazán, P. de Bernardis, M. de Petris, A. P. de Taoro, G. Garde, R. T. Génova-Santos, A. Gomez, M. F. Gómez-Renasco, J. Goupy, C. Hoarau, R. Hoyland, G. Lagache, J. Marpaud, M. Marton , et al. (13 additional authors not shown)

Abstract: Kinetic inductance detectors (KIDs) have been proven as reliable systems for astrophysical observations, especially in the millimetre range. Their compact size enables to optimally fill the focal plane, thus boosting sensitivity. The KISS (KIDs Interferometric Spectral Surveyor) instrument is a millimetre camera that consists of two KID arrays of 316 pixels each coupled to a Martin-Puplett interfe… ▽ More Kinetic inductance detectors (KIDs) have been proven as reliable systems for astrophysical observations, especially in the millimetre range. Their compact size enables to optimally fill the focal plane, thus boosting sensitivity. The KISS (KIDs Interferometric Spectral Surveyor) instrument is a millimetre camera that consists of two KID arrays of 316 pixels each coupled to a Martin-Puplett interferometer (MPI). The addition of the MPI grants the KIDs camera the ability to provide spectral information in the 100 and 300 GHz range. In this paper we report the main properties of the KISS instrument and its observations. We also describe the calibration and data analysis procedures used. We present a complete model of the observed data including the sky signal and several identified systematics. We have developed a full photometric and spectroscopic data analysis pipeline that translates our observations into science-ready products. We show examples of the results of this pipeline on selected sources: Moon, Jupiter and Venus. We note the presence of a deficit of response with respect to expectations and laboratory measurements. The detectors noise level is consistent with values obtained during laboratory measurements, pointing to a sub-optimal coupling between the instrument and the telescope as the most probable origin for the problem. This deficit is large enough as to prevent the detection of galaxy clusters, which were KISS main scientific objective. Nevertheless, we have demonstrated the feasibility of this kind of instrument, in the prospect for other KID interferometers (such as the CONCERTO instrument). As this regard, we have developed key instrumental technologies such as optical conception, readout electronics and raw calibration procedures, as well as, adapted data analysis procedures. △ Less

Submitted 30 September, 2024; originally announced September 2024.

Comments: 23 pages, 15 figures. Accepted for publication in Publications of the Astronomical Society of the Pacific

Journal ref: Publications of the Astronomical Society of the Pacific, Volume 136, Issue 11, id.114505 (2024) 19 pp

Toward the first cosmological results of the NIKA2 Sunyaev-Zeldovich Large Program: The SZ-Mass scaling relation

Authors: A. Moyer-Anin, R. Adam, P. Ade, H. Ajeddig, P. André, E. Artis, H. Aussel, I. Bartalucci, A. Beelen, A. Benoît, S. Berta, L. Bing, B. Bolliet, O. Bourrion, M. Calvo, A. Catalano, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen, G. Ejlali, A. Ferragamo, A. Gomez, J. Goupy, C. Hanser , et al. (31 additional authors not shown)

Abstract: In Sunyaev-Zeldovich (SZ) cluster cosmology, two tools are needed to be able to exploit data from large scale surveys in the millimeter-wave domain. An accurate description of the IntraCluster Medium (ICM) pressure profile is needed along with the scaling relation connecting the SZ brightness to the mass. With its high angular resolution and large field of view, The NIKA2 camera, operating at 150… ▽ More In Sunyaev-Zeldovich (SZ) cluster cosmology, two tools are needed to be able to exploit data from large scale surveys in the millimeter-wave domain. An accurate description of the IntraCluster Medium (ICM) pressure profile is needed along with the scaling relation connecting the SZ brightness to the mass. With its high angular resolution and large field of view, The NIKA2 camera, operating at 150 and 260 GHz, is perfectly suited for precise cluster SZ mapping. The SZ Large Program (LPSZ) of the NIKA2 collaboration is dedicated to the observation of a sample of 38 SZ-selected clusters at intermediate to high redshift and observed both in SZ and X-ray. The current status is that all LPSZ clusters have been observed and the analysis toward the final results is ongoing. We present in detail how NIKA2-LPSZ will obtain a robust estimation of the SZ-Mass scaling relation and how it will be used to obtain cosmological constraints. △ Less

Submitted 2 September, 2024; originally announced September 2024.

Comments: 4 pages, 3 figures, contribution to the 2024 Cosmology session of the 58th Rencontres de Moriond

LiteBIRD Science Goals and Forecasts. Mapping the Hot Gas in the Universe

Authors: M. Remazeilles, M. Douspis, J. A. Rubiño-Martín, A. J. Banday, J. Chluba, P. de Bernardis, M. De Petris, C. Hernández-Monteagudo, G. Luzzi, J. Macias-Perez, S. Masi, T. Namikawa, L. Salvati, H. Tanimura, K. Aizawa, A. Anand, J. Aumont, C. Baccigalupi, M. Ballardini, R. B. Barreiro, N. Bartolo, S. Basak, M. Bersanelli, D. Blinov, M. Bortolami , et al. (82 additional authors not shown)

Abstract: We assess the capabilities of the LiteBIRD mission to map the hot gas distribution in the Universe through the thermal Sunyaev-Zeldovich (SZ) effect. Our analysis relies on comprehensive simulations incorporating various sources of Galactic and extragalactic foreground emission, while accounting for specific instrumental characteristics of LiteBIRD, such as detector sensitivities, frequency-depend… ▽ More We assess the capabilities of the LiteBIRD mission to map the hot gas distribution in the Universe through the thermal Sunyaev-Zeldovich (SZ) effect. Our analysis relies on comprehensive simulations incorporating various sources of Galactic and extragalactic foreground emission, while accounting for specific instrumental characteristics of LiteBIRD, such as detector sensitivities, frequency-dependent beam convolution, inhomogeneous sky scanning, and $1/f$ noise. We implement a tailored component-separation pipeline to map the thermal SZ Compton $y$-parameter over 98% of the sky. Despite lower angular resolution for galaxy cluster science, LiteBIRD provides full-sky coverage and, compared to the Planck satellite, enhanced sensitivity, as well as more frequency bands to enable the construction of an all-sky $y$-map, with reduced foreground contamination at large and intermediate angular scales. By combining LiteBIRD and Planck channels in the component-separation pipeline, we obtain an optimal $y$-map that leverages the advantages of both experiments, with the higher angular resolution of the Planck channels enabling the recovery of compact clusters beyond the LiteBIRD beam limitations, and the numerous sensitive LiteBIRD channels further mitigating foregrounds. The added value of LiteBIRD is highlighted through the examination of maps, power spectra, and one-point statistics of the various sky components. After component separation, the $1/f$ noise from LiteBIRD is effectively mitigated below the thermal SZ signal at all multipoles. Cosmological constraints on $S_8=σ_8\left(Ω_{\rm m}/0.3\right)^{0.5}$ obtained from the LiteBIRD-Planck combined $y$-map power spectrum exhibits a 15% reduction in uncertainty compared to constraints from Planck alone. This improvement can be attributed to the increased portion of uncontaminated sky available in the LiteBIRD-Planck combined $y$-map. △ Less

Submitted 23 October, 2024; v1 submitted 24 July, 2024; originally announced July 2024.

Comments: 38 pages, 13 figures, abstract shortened. Updated to match version accepted by JCAP

Reconsidering the dynamical states of galaxy clusters using PCA and UMAP

Authors: Roan Haggar, Federico De Luca, Marco De Petris, Elizaveta Sazonova, James E. Taylor, Alexander Knebe, Meghan E. Gray, Frazer R. Pearce, Ana Contreras-Santos, Weiguang Cui, Ulrike Kuchner, Robert A. Mostoghiu Paun, Chris Power

Abstract: Numerous metrics exist to quantify the dynamical state of galaxy clusters, both observationally and within simulations. Many of these correlate strongly with one another, but it is not clear whether all of these measures probe the same intrinsic properties. In this work, we use two different statistical approaches -- principal component analysis (PCA) and uniform manifold approximation and project… ▽ More Numerous metrics exist to quantify the dynamical state of galaxy clusters, both observationally and within simulations. Many of these correlate strongly with one another, but it is not clear whether all of these measures probe the same intrinsic properties. In this work, we use two different statistical approaches -- principal component analysis (PCA) and uniform manifold approximation and projection (UMAP) -- to investigate which dynamical properties of a cluster are in fact the best descriptors of its dynamical state. We use measurements taken directly from The Three Hundred suite of galaxy cluster simulations, as well as morphological properties calculated using mock X-ray and SZ maps of the same simulated clusters. We find that four descriptions of dynamical state naturally arise, and although correlations exist between these, a given cluster can be "dynamically relaxed" according to all, none, or some of these four descriptions. These results demonstrate that it is highly important for future observational and theoretical studies to consider in which sense clusters are dynamically relaxed. Cluster dynamical states are complex and multi-dimensional, and so it is not meaningful to classify them simply as "relaxed" and "unrelaxed" based on a single linear scale. △ Less

Submitted 21 June, 2024; originally announced June 2024.

Comments: 18 pages, 7 figures, 3 tables, accepted for publication in MNRAS

Measuring the CMB spectral distortions with COSMO: the multi-mode antenna system

Authors: E. Manzan, L. Albano, C. Franceschet, E. S. Battistelli, P. de Bernardis, M. Bersanelli, F. Cacciotti, A. Capponi, F. Columbro, G. Conenna, G. Coppi, A. Coppolecchia, G. D'Alessandro, G. De Gasperis, M. De Petris, M. Gervasi, G. Isopi, L. Lamagna, A. Limonta, E. Marchitelli, S. Masi, A. Mennella, F. Montonati, F. Nati, A. Occhiuzzi , et al. (7 additional authors not shown)

Abstract: In this work, we present the design and manufacturing of the two multi-mode antenna arrays of the COSMO experiment and the preliminary beam pattern measurements of their fundamental mode compared with simulations. COSMO is a cryogenic Martin-Puplett Fourier Transform Spectrometer that aims at measuring the isotropic y-type spectral distortion of the Cosmic Microwave Background from Antarctica, b… ▽ More In this work, we present the design and manufacturing of the two multi-mode antenna arrays of the COSMO experiment and the preliminary beam pattern measurements of their fundamental mode compared with simulations. COSMO is a cryogenic Martin-Puplett Fourier Transform Spectrometer that aims at measuring the isotropic y-type spectral distortion of the Cosmic Microwave Background from Antarctica, by performing differential measurements between the sky and an internal, cryogenic reference blackbody. To reduce the atmospheric contribution, a spinning wedge mirror performs fast sky-dips at varying elevations while fast, low-noise Kinetic Inductance detectors scan the interferogram. Two arrays of antennas couple the radiation to the detectors. Each array consists of nine smooth-walled multi-mode feed-horns, operating in the $120-180$ GHz and $210-300$ GHz range, respectively. The multi-mode propagation helps increase the instrumental sensitivity without employing large focal planes with hundreds of detectors. The two arrays have a step-linear and a linear profile, respectively, and are obtained by superimposing aluminum plates made with CNC milling. The simulated multi-mode beam pattern has a $\sim 20^{\circ} - 26^{\circ}$ FWHM for the low-frequency array and $\sim 16^{\circ}$ FWHM for the high-frequency one. The side lobes are below $-15$ dB. To characterize the antenna response, we measured the beam pattern of the fundamental mode using a Vector Network Analyzer, in far-field conditions inside an anechoic chamber at room temperature. We completed the measurements of the low-frequency array and found a good agreement with the simulations. We also identified a few non-idealities that we attribute to the measuring setup and will further investigate. A comprehensive multi-mode measurement will be feasible at cryogenic temperature once the full receiver is integrated. △ Less

Submitted 13 June, 2024; originally announced June 2024.

Comments: To appear in Proceedings of the SPIE Astronomical Telescopes + Instrumentation, 2024

The LiteBIRD mission to explore cosmic inflation

Authors: T. Ghigna, A. Adler, K. Aizawa, H. Akamatsu, R. Akizawa, E. Allys, A. Anand, J. Aumont, J. Austermann, S. Azzoni, C. Baccigalupi, M. Ballardini, A. J. Banday, R. B. Barreiro, N. Bartolo, S. Basak, A. Basyrov, S. Beckman, M. Bersanelli, M. Bortolami, F. Bouchet, T. Brinckmann, P. Campeti, E. Carinos, A. Carones , et al. (134 additional authors not shown)

Abstract: LiteBIRD, the next-generation cosmic microwave background (CMB) experiment, aims for a launch in Japan's fiscal year 2032, marking a major advancement in the exploration of primordial cosmology and fundamental physics. Orbiting the Sun-Earth Lagrangian point L2, this JAXA-led strategic L-class mission will conduct a comprehensive mapping of the CMB polarization across the entire sky. During its 3-… ▽ More LiteBIRD, the next-generation cosmic microwave background (CMB) experiment, aims for a launch in Japan's fiscal year 2032, marking a major advancement in the exploration of primordial cosmology and fundamental physics. Orbiting the Sun-Earth Lagrangian point L2, this JAXA-led strategic L-class mission will conduct a comprehensive mapping of the CMB polarization across the entire sky. During its 3-year mission, LiteBIRD will employ three telescopes within 15 unique frequency bands (ranging from 34 through 448 GHz), targeting a sensitivity of 2.2\,$μ$K-arcmin and a resolution of 0.5$^\circ$ at 100\,GHz. Its primary goal is to measure the tensor-to-scalar ratio $r$ with an uncertainty $δr = 0.001$, including systematic errors and margin. If $r \geq 0.01$, LiteBIRD expects to achieve a $>5σ$ detection in the $\ell=$2-10 and $\ell=$11-200 ranges separately, providing crucial insight into the early Universe. We describe LiteBIRD's scientific objectives, the application of systems engineering to mission requirements, the anticipated scientific impact, and the operations and scanning strategies vital to minimizing systematic effects. We will also highlight LiteBIRD's synergies with concurrent CMB projects. △ Less

Submitted 4 June, 2024; originally announced June 2024.

Comments: 23 pages, 9 figures, 1 table, SPIE Astronomical Telescopes + Instrumentation 2024

The Three Hundred project: Estimating the dependence of gas filaments on the mass of galaxy clusters

Authors: Sara Santoni, Marco De Petris, Gustavo Yepes, Antonio Ferragamo, Matteo Bianconi, Meghan E. Gray, Ulrike Kuchner, Frazer R. Pearce, Weiguang Cui, Stefano Ettori

Abstract: Galaxy clusters are located in the densest areas of the universe and are intricately connected to larger structures through the filamentary network of the Cosmic Web. In this scenario, matter flows from areas of lower density to higher density. As a result, the properties of galaxy clusters are deeply influenced by the filaments that are attached to them, which are quantified by a parameter known… ▽ More Galaxy clusters are located in the densest areas of the universe and are intricately connected to larger structures through the filamentary network of the Cosmic Web. In this scenario, matter flows from areas of lower density to higher density. As a result, the properties of galaxy clusters are deeply influenced by the filaments that are attached to them, which are quantified by a parameter known as connectivity. We explore the dependence of gas-traced filaments connected to galaxy clusters on the mass and dynamical state of the cluster. Moreover, we evaluate the effectiveness of the cosmic web extraction procedure from the gas density maps of simulated cluster regions. Using the DisPerSE cosmic web finder, we identify filamentary structures from 3D gas particle distribution in 324 simulated regions of $30 \, h^{-1}$ Mpc side from The Three Hundred hydrodynamical simulation at redshifts z=0, 1, and 2. We estimate the connectivity at various apertures for $\sim3000$ groups and clusters spanning a mass range from $10^{13} \, h^{-1} \, M_{\odot}$ to $10^{15} \, h^{-1} \, M_{\odot}$. Relationships between connectivity and cluster properties like radius, mass, dynamical state and hydrostatic mass bias are explored. We show that the connectivity is strongly correlated with the mass of galaxy clusters, with more massive clusters being on average more connected. This finding aligns with previous studies in literature, both from observational and simulated data sets. Additionally, we observe a dependence of the connectivity on the aperture at which it is estimated. We find that connectivity decreases with cosmic time, while no dependencies on the dynamical state and hydrostatic mass bias of the cluster are found. Lastly, we observe a significant agreement between the connectivity measured from gas-traced and mock-galaxies-traced filaments in the simulation. △ Less

Submitted 12 November, 2024; v1 submitted 27 May, 2024; originally announced May 2024.

Comments: 12 pages, 11 figures Accepted for publication in A&A on 28/10/2024. Reproduced with permission from Astronomy & Astrophysics, copyright ESO

Journal ref: A&A 692, A44 (2024)

Euclid. I. Overview of the Euclid mission

Authors: Euclid Collaboration, Y. Mellier, Abdurro'uf, J. A. Acevedo Barroso, A. Achúcarro, J. Adamek, R. Adam, G. E. Addison, N. Aghanim, M. Aguena, V. Ajani, Y. Akrami, A. Al-Bahlawan, A. Alavi, I. S. Albuquerque, G. Alestas, G. Alguero, A. Allaoui, S. W. Allen, V. Allevato, A. V. Alonso-Tetilla, B. Altieri, A. Alvarez-Candal, S. Alvi, A. Amara , et al. (1115 additional authors not shown)

Abstract: The current standard model of cosmology successfully describes a variety of measurements, but the nature of its main ingredients, dark matter and dark energy, remains unknown. Euclid is a medium-class mission in the Cosmic Vision 2015-2025 programme of the European Space Agency (ESA) that will provide high-resolution optical imaging, as well as near-infrared imaging and spectroscopy, over about 14… ▽ More The current standard model of cosmology successfully describes a variety of measurements, but the nature of its main ingredients, dark matter and dark energy, remains unknown. Euclid is a medium-class mission in the Cosmic Vision 2015-2025 programme of the European Space Agency (ESA) that will provide high-resolution optical imaging, as well as near-infrared imaging and spectroscopy, over about 14,000 deg^2 of extragalactic sky. In addition to accurate weak lensing and clustering measurements that probe structure formation over half of the age of the Universe, its primary probes for cosmology, these exquisite data will enable a wide range of science. This paper provides a high-level overview of the mission, summarising the survey characteristics, the various data-processing steps, and data products. We also highlight the main science objectives and expected performance. △ Less

Submitted 24 September, 2024; v1 submitted 22 May, 2024; originally announced May 2024.

Comments: Accepted for publication in the A&A special issue`Euclid on Sky'

Journal ref: A&A 697, A1 (2025)

Generating Galaxy Clusters Mass Density Maps from Mock Multiview Images via Deep Learning

Authors: Daniel de Andres, Weiguang Cui, Gustavo Yepes, Marco De Petris, Gianmarco Aversano, Antonio Ferragamo, Federico De Luca, A. Jiménez Muñoz

Abstract: Galaxy clusters are composed of dark matter, gas and stars. Their dark matter component, which amounts to around 80\% of the total mass, cannot be directly observed but traced by the distribution of diffused gas and galaxy members. In this work, we aim to infer the cluster's projected total mass distribution from mock observational data, i.e. stars, Sunyaev-Zeldovich, and X-ray, by training deep l… ▽ More Galaxy clusters are composed of dark matter, gas and stars. Their dark matter component, which amounts to around 80\% of the total mass, cannot be directly observed but traced by the distribution of diffused gas and galaxy members. In this work, we aim to infer the cluster's projected total mass distribution from mock observational data, i.e. stars, Sunyaev-Zeldovich, and X-ray, by training deep learning models. To this end, we have created a multiview images dataset from {\sc{The Three Hundred}} simulation that is optimal for training Machine Learning models. We further study deep learning architectures based on the U-Net to account for single-input and multi-input models. We show that the predicted mass distribution agrees well with the true one. △ Less

Submitted 9 April, 2024; v1 submitted 8 April, 2024; originally announced April 2024.

Comments: To appear in Proc. of the mm Universe 2023 conference, Grenoble (France), June 2023, published by F. Mayet et al. (Eds), EPJ Web of conferences, EDP Sciences

OLIMPO: a Balloon-Borne SZE Imager to Probe ICM Dynamics and the WHIM

Authors: Jack Sayers, Camille Avestruz, Ritoban Basu Thakur, Elia Stefano Battistelli, Esra Bulbul, Federico Caccioti, Fabio Columbro, Alessandro Coppolecchia, Scott Cray, Giuseppe D'Alessandro, Paolo de Bernardis, Marco de Petris, Shaul Hanany, Luca Lamagna, Erwin Lau, Silvia Masi, Allesandro Paiella, Giorgio Pettinari, Francesco Piacentini, Eitan Rapaport, Larry Rudnick, Irina Zhuravleva, John ZuHuone

Abstract: OLIMPO is a proposed Antarctic balloon-borne Sunyaev-Zel'dovich effect (SZE) imager to study gas dynamics associated with structure formation along with the properties of the warm-hot intergalactic medium (WHIM) residing in the connective filaments. During a 25 day flight OLIMPO will image a total of 10 z~0.05 galaxy clusters and 8 bridges at 145, 250, 365, and 460 GHz at an angular resolution of… ▽ More OLIMPO is a proposed Antarctic balloon-borne Sunyaev-Zel'dovich effect (SZE) imager to study gas dynamics associated with structure formation along with the properties of the warm-hot intergalactic medium (WHIM) residing in the connective filaments. During a 25 day flight OLIMPO will image a total of 10 z~0.05 galaxy clusters and 8 bridges at 145, 250, 365, and 460 GHz at an angular resolution of 1.0'-3.3'. The maps will be significantly deeper than those planned from CMB-S4 and CCAT-P, and will have excellent fidelity to the large angular scales of our low-z targets, which are difficult to probe from the ground. In combination with X-ray data from eROSITA and XRISM we will transform our current static view of galaxy clusters into a full dynamic picture by measuring the internal intra-cluster medium (ICM) velocity structure with the kinematic SZE, X-ray spectroscopy, and the power spectrum of ICM fluctuations. Radio observations from ASKAP and MeerKAT will be used to better understand the connection between ICM turbulence and shocks with the relativistic plasma. Beyond the cluster boundary, we will combine thermal SZE maps from OLIMPO with X-ray imaging from eROSITA to measure the thermodynamics of the WHIM residing in filaments, providing a better understanding of its properties and its contribution to the total baryon budget. △ Less

Submitted 5 April, 2024; originally announced April 2024.

Comments: From the proceedings of the mm Universe 2023

3D scaling laws and projection effects in The300-NIKA2 Sunyaev-Zeldovich Large Program Twin Samples

Authors: A. Paliwal, W. Cui, D. de Andrés, M. De Petris, A. Ferragamo, C. Hanser, J. -F. Macías-Pérez, F. Mayet, A. Moyer-Anin, M. Muñoz-Echeverría, L. Perotto, E. Rasia, G. Yepes

Abstract: The abundance of galaxy clusters with mass and redshift is a well-known cosmological probe. The cluster mass is a key parameter for studies that aim to constrain cosmological parameters using galaxy clusters, making it critical to understand and properly account for the errors in its estimates. Subsequently, it becomes important to correctly calibrate scaling relations between observables like the… ▽ More The abundance of galaxy clusters with mass and redshift is a well-known cosmological probe. The cluster mass is a key parameter for studies that aim to constrain cosmological parameters using galaxy clusters, making it critical to understand and properly account for the errors in its estimates. Subsequently, it becomes important to correctly calibrate scaling relations between observables like the integrated Compton parameter and the mass of the cluster. The NIKA2 Sunyaev-Zeldovich Large program (LPSZ) enables one to map the intracluster medium profiles in the mm-wavelength band with great details (resolution of $11 \ \mathrm{\&}\ 17^{\prime \prime}$ at $1.2 \ \mathrm{\&}\ 2 $ mm, respectively) and hence, to estimate the cluster hydrostatic mass more precisely than previous SZ observations. However, there are certain systematic effects which can only be accounted for with the use of simulations. For this purpose, we employ THE THREE HUNDRED simulations which have been modelled with a range of physics modules to simulate galaxy clusters. The so-called twin samples are constructed by picking synthetic clusters of galaxies with properties close to the observational targets of the LPSZ. In particular, we use the Compton parameter maps and projected total mass maps of these twin samples along 29 different lines of sight. We investigate the scatter that projection induces on the total masses. Eventually, we consider the statistical values along different lines of sight to construct a kind of 3D scaling law between the integrated Compton parameter, total mass, and overdensity of the galaxy clusters to determine the overdensity that is least impacted by the projection effect. △ Less

Submitted 4 April, 2024; originally announced April 2024.

Comments: to appear in Proc. of the mm Universe 2023 conference, Grenoble (France), June 2023, published by F. Mayet et al. (Eds), EPJ Web of conferences, EDP Sciences

CHEX-MATE : turbulence in the ICM from X-ray surface brightness fluctuations

Authors: Simon Dupourqué, Nicolas Clerc, Etienne Pointecouteau, Dominique Eckert, Massimo Gaspari, Lorenzo Lovisari, Gabriel W. Pratt, Elena Rasia, Mariachiara Rossetti, Franco Vazza, Marco Balboni, Iacopo Bartalucci, Hervé Bourdin, Federico De Luca, Marco De Petris, Stefano Ettori, Simona Ghizzardi, Pasquale Mazzotta

Abstract: The intra-cluster medium is prone to turbulent motion that will contribute to the non-thermal heating of the gas, complicating the use of galaxy clusters as cosmological probes. Indirect approaches can estimate the intensity and structure of turbulent motions by studying the associated fluctuations in gas density and X-ray surface brightness. In this work, we want to constrain the gas density fluc… ▽ More The intra-cluster medium is prone to turbulent motion that will contribute to the non-thermal heating of the gas, complicating the use of galaxy clusters as cosmological probes. Indirect approaches can estimate the intensity and structure of turbulent motions by studying the associated fluctuations in gas density and X-ray surface brightness. In this work, we want to constrain the gas density fluctuations at work in the CHEX-MATE sample to obtain a detailed view of their properties in a large population of clusters. We use a simulation-based approach to constrain the parameters of the power spectrum of density fluctuations, assuming a Kolmogorov-like spectrum and including the sample variance, further providing an approximate likelihood for each cluster. This method requires clusters to be not too disturbed, as fluctuations can originate from dynamic processes such as merging. Accordingly, we remove the less relaxed clusters (centroid shift $w>0.02$) from our sample, resulting in a sample of 64 clusters. We define different subsets of CHEX-MATE to determine properties of density fluctuations as a function of dynamical state, mass and redshift, and investigate the correlation with the presence or not of a radio halo. We found a positive correlation between the dynamical state and density fluctuation variance, a non-trivial behaviour with mass and no specific trend with redshift or the presence/absence of a radio halo. The injection scale is mostly constrained by the core region. The slope in the inertial range is consistent with Kolmogorov theory. When interpreted as originating from turbulent motion, the density fluctuations in $R_{500}$ yield an average Mach number of $M_{3D}\simeq 0.4\pm 0.2$, an associated non-thermal pressure support of $ P_{turb}/P_{tot}\simeq (9\pm 6) \%$ or a hydrostatic mass bias $b_{turb}\simeq 0.09\pm 0.06$, in line with what is expected from the literature. △ Less

Submitted 5 March, 2024; originally announced March 2024.

Comments: Accepted for publication in A&A, abstract slightly abridged for Arxiv

Journal ref: A&A 687, A58 (2024)

Faint millimeter NIKA2 dusty star-forming galaxies: finding the high-redshift population

Authors: L. -J. Bing, A. Beelen, G. Lagache, R. Adam, P. Ade, H. Ajeddig, P. André, E. Artis, H. Aussel, A. Benoît, S. Berta, M. Béthermin, O. Bourrion, M. Calvo, A. Catalano, M. De Petris, F. -X. Désert, S. Doyle, E. F. C. Driessen, A. Gomez, J. Goupy, F. Kéruzoré, C. Kramer, B. Ladjelate, S. Leclercq , et al. (24 additional authors not shown)

Abstract: We develop a new framework to constrain the source redshift. The method jointly accounts for the detection/non-detection of spectral lines and the prior information from the photometric redshift and total infrared luminosity from spectral energy distribution analysis. The method uses the estimated total infrared luminosity to predict the line fluxes at given redshifts and generates model spectra.… ▽ More We develop a new framework to constrain the source redshift. The method jointly accounts for the detection/non-detection of spectral lines and the prior information from the photometric redshift and total infrared luminosity from spectral energy distribution analysis. The method uses the estimated total infrared luminosity to predict the line fluxes at given redshifts and generates model spectra. The redshift-dependent spectral models are then compared with the observed spectra to find the redshift. Results. We apply the aforementioned joint redshift analysis method to four high-z dusty star-forming galaxy candidates selected from the NIKA2 observations of the HLSJ091828.6+514223 (HLS) field, and further observed by NOEMA with blind spectral scans. These sources only have SPIRE/Herschel photometry as ancillary data. They were selected because of very faint or no SPIRE counterparts, as to bias the sample towards the highest redshift candidates. The method finds the spectroscopic redshift of 4 in the 5 NOEMA-counterpart detected sources, with z>3. Based on these measurements, we derive the CO/[CI] lines and millimeter continuum fluxes from the NOEMA data and study their ISM and star-formation properties. We find cold dust temperatures in some of the HLS sources compared to the general population of sub-millimeter galaxies, which might be related to the bias introduced by the SPIRE-dropout selection. Our sources, but one, have short gas depletion time of a few hundred Myrs, which is typical among high-z sub-millimeter galaxies. The only exception shows a longer gas depletion time, up to a few Gyrs, comparable to that of main-sequence galaxies at the same redshift. Furthermore, we identify a possible over-density of dusty star-forming galaxies at z=5.2, traced by two sources in our sample, as well as the lensed galaxy HLSJ091828.6+514223. (abridged) △ Less

Submitted 1 March, 2024; originally announced March 2024.

Comments: A&A in press

CHEX-MATE: Robust reconstruction of temperature profiles in galaxy clusters with XMM-Newton

Authors: M. Rossetti, D. Eckert, F. Gastaldello, E. Rasia, G. W. Pratt, S. Ettori, S. Molendi, M. Arnaud, M. Balboni, I. Bartalucci, R. M. Batalha, S. Borgani, H. Bourdin, S. De Grandi, F. De Luca, M. De Petris, W. Forman, M. Gaspari, S. Ghizzardi, A. Iqbal, S. Kay, L. Lovisari, B. J. Maughan, P. Mazzotta, E. Pointecouteau , et al. (3 additional authors not shown)

Abstract: The "Cluster HEritage project with \xmm: Mass Assembly and Thermodynamics at the Endpoint of structure formation" (CHEX-MATE) is a multi-year Heritage program, to obtain homogeneous XMM-Newton observations of a representative sample of 118 galaxy clusters. The observations are tuned to reconstruct the distribution of the main thermodynamic quantities of the ICM up to $R_{500}$ and to obtain indivi… ▽ More The "Cluster HEritage project with \xmm: Mass Assembly and Thermodynamics at the Endpoint of structure formation" (CHEX-MATE) is a multi-year Heritage program, to obtain homogeneous XMM-Newton observations of a representative sample of 118 galaxy clusters. The observations are tuned to reconstruct the distribution of the main thermodynamic quantities of the ICM up to $R_{500}$ and to obtain individual mass measurements, via the hydrostatic-equilibrium equation, with a precision of 15-20%. Temperature profiles are a necessary ingredient for the scientific goals of the project and it is thus crucial to derive the best possible temperature measurements from our data. This is why we have built a new pipeline for spectral extraction and analysis of XMM-Newton data, based on a new physically motivated background model and on a Bayesian approach with Markov Chain Monte Carlo (MCMC) methods, that we present in this paper for the first time. We applied this new method to a subset of 30 galaxy clusters representative of the CHEX-MATE sample and show that we can obtain reliable temperature measurements up to regions where the source intensity is as low as 20% of the background, keeping systematic errors below 10%. We compare the median profile of our sample and the best fit slope at large radii with literature results and we find a good agreement with other measurements based on XMM-Newton data. Conversely, when we exclude from our analysis the most contaminated regions, where the source intensity is below 20 of the background, we find significantly flatter profiles, in agreement with predictions from numerical simulations and independent measurements with a combination of Sunyaev-Zeldovich and X-ray imaging data. △ Less

Submitted 28 February, 2024; originally announced February 2024.

Comments: Accepted for publication in Astronomy & Astrophysics. Table C.1. available in electronic format at http://xmm-heritage.oas.inaf.it/data/Rossetti24_table_cds.dat

Journal ref: A&A 686, A68 (2024)

Impact of beam far side-lobe knowledge in the presence of foregrounds for LiteBIRD

Authors: C. Leloup, G. Patanchon, J. Errard, C. Franceschet, J. E. Gudmundsson, S. Henrot-Versillé, H. Imada, H. Ishino, T. Matsumura, G. Puglisi, W. Wang, A. Adler, J. Aumont, R. Aurlien, C. Baccigalupi, M. Ballardini, A. J. Banday, R. B. Barreiro, N. Bartolo, A. Basyrov, M. Bersanelli, D. Blinov, M. Bortolami, T. Brinckmann, P. Campeti , et al. (86 additional authors not shown)

Abstract: We present a study of the impact of an uncertainty in the beam far side-lobe knowledge on the measurement of the Cosmic Microwave Background $B$-mode signal at large scale. It is expected to be one of the main source of systematic effects in future CMB observations. Because it is crucial for all-sky survey missions to take into account the interplays between beam systematic effects and all the dat… ▽ More We present a study of the impact of an uncertainty in the beam far side-lobe knowledge on the measurement of the Cosmic Microwave Background $B$-mode signal at large scale. It is expected to be one of the main source of systematic effects in future CMB observations. Because it is crucial for all-sky survey missions to take into account the interplays between beam systematic effects and all the data analysis steps, the primary goal of this paper is to provide the methodology to carry out the end-to-end study of their effect for a space-borne CMB polarization experiment, up to the cosmological results in the form of a bias $δr$ on the tensor-to-scalar ratio $r$. LiteBIRD is dedicated to target the measurement of CMB primordial $B$ modes by reaching a sensitivity of $σ\left( r \right) \leq 10^{-3}$ assuming $r=0$. As a demonstration of our framework, we derive the relationship between the knowledge of the beam far side-lobes and the tentatively allocated error budget under given assumptions on design, simulation and component separation method. We assume no mitigation of the far side-lobes effect at any stage of the analysis pipeline. We show that $δr$ is mostly due to the integrated fractional power difference between the estimated beams and the true beams in the far side-lobes region, with little dependence on the actual shape of the beams, for low enough $δr$. Under our set of assumptions, in particular considering the specific foreground cleaning method we used, we find that the integrated fractional power in the far side-lobes should be known at a level as tight as $\sim 10^{-4}$, to achieve the required limit on the bias $δr < 1.9 \times 10^{-5}$. The framework and tools developed for this study can be easily adapted to provide requirements under different design, data analysis frameworks and for other future space-borne experiments beyond LiteBIRD. △ Less

Submitted 14 December, 2023; originally announced December 2023.

LiteBIRD Science Goals and Forecasts: Improving Sensitivity to Inflationary Gravitational Waves with Multitracer Delensing

Authors: T. Namikawa, A. I. Lonappan, C. Baccigalupi, N. Bartolo, D. Beck, K. Benabed, A. Challinor, P. Diego-Palazuelos, J. Errard, S. Farrens, A. Gruppuso, N. Krachmalnicoff, M. Migliaccio, E. Martínez-González, V. Pettorino, G. Piccirilli, M. Ruiz-Granda, B. Sherwin, J. Starck, P. Vielva, R. Akizawa, A. Anand, J. Aumont, R. Aurlien, S. Azzoni , et al. (97 additional authors not shown)

Abstract: We estimate the efficiency of mitigating the lensing $B$-mode polarization, the so-called delensing, for the $LiteBIRD$ experiment with multiple external data sets of lensing-mass tracers. The current best bound on the tensor-to-scalar ratio, $r$, is limited by lensing rather than Galactic foregrounds. Delensing will be a critical step to improve sensitivity to $r$ as measurements of $r$ become mo… ▽ More We estimate the efficiency of mitigating the lensing $B$-mode polarization, the so-called delensing, for the $LiteBIRD$ experiment with multiple external data sets of lensing-mass tracers. The current best bound on the tensor-to-scalar ratio, $r$, is limited by lensing rather than Galactic foregrounds. Delensing will be a critical step to improve sensitivity to $r$ as measurements of $r$ become more and more limited by lensing. In this paper, we extend the analysis of the recent $LiteBIRD$ forecast paper to include multiple mass tracers, i.e., the CMB lensing maps from $LiteBIRD$ and CMB-S4-like experiment, cosmic infrared background, and galaxy number density from $Euclid$- and LSST-like survey. We find that multi-tracer delensing will further improve the constraint on $r$ by about $20\%$. In $LiteBIRD$, the residual Galactic foregrounds also significantly contribute to uncertainties of the $B$-modes, and delensing becomes more important if the residual foregrounds are further reduced by an improved component separation method. △ Less

Submitted 8 December, 2023; originally announced December 2023.

Comments: 21 pages, 7 figures

Journal ref: JCAP 06 (2024) 010

LiteBIRD Science Goals and Forecasts: A full-sky measurement of gravitational lensing of the CMB

Authors: A. I. Lonappan, T. Namikawa, G. Piccirilli, P. Diego-Palazuelos, M. Ruiz-Granda, M. Migliaccio, C. Baccigalupi, N. Bartolo, D. Beck, K. Benabed, A. Challinor, J. Errard, S. Farrens, A. Gruppuso, N. Krachmalnicoff, E. Martínez-González, V. Pettorino, B. Sherwin, J. Starck, P. Vielva, R. Akizawa, A. Anand, J. Aumont, R. Aurlien, S. Azzoni , et al. (97 additional authors not shown)

Abstract: We explore the capability of measuring lensing signals in $LiteBIRD$ full-sky polarization maps. With a $30$ arcmin beam width and an impressively low polarization noise of $2.16\,μ$K-arcmin, $LiteBIRD$ will be able to measure the full-sky polarization of the cosmic microwave background (CMB) very precisely. This unique sensitivity also enables the reconstruction of a nearly full-sky lensing map u… ▽ More We explore the capability of measuring lensing signals in $LiteBIRD$ full-sky polarization maps. With a $30$ arcmin beam width and an impressively low polarization noise of $2.16\,μ$K-arcmin, $LiteBIRD$ will be able to measure the full-sky polarization of the cosmic microwave background (CMB) very precisely. This unique sensitivity also enables the reconstruction of a nearly full-sky lensing map using only polarization data, even considering its limited capability to capture small-scale CMB anisotropies. In this paper, we investigate the ability to construct a full-sky lensing measurement in the presence of Galactic foregrounds, finding that several possible biases from Galactic foregrounds should be negligible after component separation by harmonic-space internal linear combination. We find that the signal-to-noise ratio of the lensing is approximately $40$ using only polarization data measured over $90\%$ of the sky. This achievement is comparable to $Planck$'s recent lensing measurement with both temperature and polarization and represents a four-fold improvement over $Planck$'s polarization-only lensing measurement. The $LiteBIRD$ lensing map will complement the $Planck$ lensing map and provide several opportunities for cross-correlation science, especially in the northern hemisphere. △ Less

Submitted 8 December, 2023; originally announced December 2023.

The hydrostatic-to-lensing mass bias from resolved X-ray and optical-IR data

Authors: M. Muñoz-Echeverría, J. F. Macías-Pérez, G. W. Pratt, E. Pointecouteau, I. Bartalucci, M. De Petris, A. Ferragamo, C. Hanser, F. Kéruzoré, F. Mayet, A. Moyer-Anin, A. Paliwal, L. Perotto, G. Yepes

Abstract: An accurate reconstruction of galaxy cluster masses is key to use this population of objects as a cosmological probe. In this work we present a study on the hydrostatic-to-lensing mass scaling relation for a sample of 53 clusters whose masses were reconstructed homogeneously in a redshift range between $z= 0.05$ and $1.07$. The $M_{500}$ mass for each cluster was indeed inferred from the mass prof… ▽ More An accurate reconstruction of galaxy cluster masses is key to use this population of objects as a cosmological probe. In this work we present a study on the hydrostatic-to-lensing mass scaling relation for a sample of 53 clusters whose masses were reconstructed homogeneously in a redshift range between $z= 0.05$ and $1.07$. The $M_{500}$ mass for each cluster was indeed inferred from the mass profiles extracted from the X-ray and lensing data, without using a priori observable-mass scaling relations. We assessed the systematic dispersion of the masses estimated with our reference analyses with respect to other published mass estimates. Accounting for this systematic scatter does not change our main results, but enables the propagation of the uncertainties related to the mass reconstruction method or used dataset. Our analysis gives a hydrostatic-to-lensing mass bias of $(1-b) =0.739^{+0.075}_{-0.070}$ and no evidence of evolution with redshift. These results are robust against possible subsample differences. △ Less

Submitted 2 December, 2023; originally announced December 2023.

Journal ref: Astronomy & Astrophysics, Volume 682, id.A147, 27 pp., February 2024

LiteBIRD Science Goals and Forecasts. A Case Study of the Origin of Primordial Gravitational Waves using Large-Scale CMB Polarization

Authors: P. Campeti, E. Komatsu, C. Baccigalupi, M. Ballardini, N. Bartolo, A. Carones, J. Errard, F. Finelli, R. Flauger, S. Galli, G. Galloni, S. Giardiello, M. Hazumi, S. Henrot-Versillé, L. T. Hergt, K. Kohri, C. Leloup, J. Lesgourgues, J. Macias-Perez, E. Martínez-González, S. Matarrese, T. Matsumura, L. Montier, T. Namikawa, D. Paoletti , et al. (85 additional authors not shown)

Abstract: We study the possibility of using the $LiteBIRD$ satellite $B$-mode survey to constrain models of inflation producing specific features in CMB angular power spectra. We explore a particular model example, i.e. spectator axion-SU(2) gauge field inflation. This model can source parity-violating gravitational waves from the amplification of gauge field fluctuations driven by a pseudoscalar "axionlike… ▽ More We study the possibility of using the $LiteBIRD$ satellite $B$-mode survey to constrain models of inflation producing specific features in CMB angular power spectra. We explore a particular model example, i.e. spectator axion-SU(2) gauge field inflation. This model can source parity-violating gravitational waves from the amplification of gauge field fluctuations driven by a pseudoscalar "axionlike" field, rolling for a few e-folds during inflation. The sourced gravitational waves can exceed the vacuum contribution at reionization bump scales by about an order of magnitude and can be comparable to the vacuum contribution at recombination bump scales. We argue that a satellite mission with full sky coverage and access to the reionization bump scales is necessary to understand the origin of the primordial gravitational wave signal and distinguish among two production mechanisms: quantum vacuum fluctuations of spacetime and matter sources during inflation. We present the expected constraints on model parameters from $LiteBIRD$ satellite simulations, which complement and expand previous studies in the literature. We find that $LiteBIRD$ will be able to exclude with high significance standard single-field slow-roll models, such as the Starobinsky model, if the true model is the axion-SU(2) model with a feature at CMB scales. We further investigate the possibility of using the parity-violating signature of the model, such as the $TB$ and $EB$ angular power spectra, to disentangle it from the standard single-field slow-roll scenario. We find that most of the discriminating power of $LiteBIRD$ will reside in $BB$ angular power spectra rather than in $TB$ and $EB$ correlations. △ Less

Submitted 23 March, 2025; v1 submitted 1 December, 2023; originally announced December 2023.

Comments: 22 pages, 13 figures. Published in JCAP 06 (2024) 008. Added comments at end of Sec. 6 reframing conclusions in more general way. Updated references

Journal ref: JCAP 06 (2024), 008

Measuring the CMB primordial B-modes with Bolometric Interferometry

Authors: A. Mennella, P. Ade, A. Almela, G. Amico, L. H. Arnaldi, J. Aumont, S. Banfi, E. S. Battistelli, B. Bélier, L. Bergé, J. -Ph. Bernard, P. de Bernardis, M. Bersanelli, J. Bonaparte, J. D. Bonilla, E. Bunn, D. Buzi, F. Cacciotti, D. Camilieri, F. Cavaliere, P. Chanial, C. Chapron, L. Colombo, F. Columbro, A. Coppolecchia , et al. (89 additional authors not shown)

Abstract: The Q&U Bolometric Interferometer for Cosmology (QUBIC) is the first bolometric interferometer designed to measure the primordial B-mode polarization of the Cosmic Microwave Background (CMB). Bolometric interferometry is a novel technique that combines the sensitivity of bolometric detectors with the control of systematic effects that is typical of interferometry, both key features in the quest fo… ▽ More The Q&U Bolometric Interferometer for Cosmology (QUBIC) is the first bolometric interferometer designed to measure the primordial B-mode polarization of the Cosmic Microwave Background (CMB). Bolometric interferometry is a novel technique that combines the sensitivity of bolometric detectors with the control of systematic effects that is typical of interferometry, both key features in the quest for the faint signal of the primordial B-modes. A unique feature is the so-called "spectral imaging", i.e., the ability to recover the sky signal in several sub-bands within the physical band during data analysis. This feature provides an in-band spectral resolution of Δν/ν \sim 0.04 that is unattainable by a traditional imager. This is a key tool for controlling the Galactic foregrounds contamination. In this paper, we describe the principles of bolometric interferometry, the current status of the QUBIC experiment and future prospects. △ Less

Submitted 5 November, 2023; originally announced November 2023.

Comments: To appear in Proc. of the mm Universe 2023 conference, Grenoble (France), June 2023, published by F. Mayet et al. (Eds), EPJ Web of conferences, EDP Sciences