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Constraints on cosmology and baryonic feedback with joint analysis of Dark Energy Survey Year 3 lensing data and ACT DR6 thermal Sunyaev-Zel'dovich effect observations
Authors:
S. Pandey,
J. C. Hill,
A. Alarcon,
O. Alves,
A. Amon,
D. Anbajagane,
F. Andrade-Oliveira,
N. Battaglia,
E. Baxter,
K. Bechtol,
M. R. Becker,
G. M. Bernstein,
J. Blazek,
S. L. Bridle,
E. Calabrese,
H. Camacho,
A. Campos,
A. Carnero Rosell,
M. Carrasco Kind,
R. Cawthon,
C. Chang,
R. Chen,
P. Chintalapati,
A. Choi,
J. Cordero
, et al. (116 additional authors not shown)
Abstract:
We present a joint analysis of weak gravitational lensing (shear) data obtained from the first three years of observations by the Dark Energy Survey and thermal Sunyaev-Zel'dovich (tSZ) effect measurements from a combination of Atacama Cosmology Telescope (ACT) and Planck data. A combined analysis of shear (which traces the projected mass) with the tSZ effect (which traces the projected gas pressu…
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We present a joint analysis of weak gravitational lensing (shear) data obtained from the first three years of observations by the Dark Energy Survey and thermal Sunyaev-Zel'dovich (tSZ) effect measurements from a combination of Atacama Cosmology Telescope (ACT) and Planck data. A combined analysis of shear (which traces the projected mass) with the tSZ effect (which traces the projected gas pressure) can jointly probe both the distribution of matter and the thermodynamic state of the gas, accounting for the correlated effects of baryonic feedback on both observables. We detect the shear$~\times~$tSZ cross-correlation at a 21$σ$ significance, the highest to date, after minimizing the bias from cosmic infrared background leakage in the tSZ map. By jointly modeling the small-scale shear auto-correlation and the shear$~\times~$tSZ cross-correlation, we obtain $S_8 = 0.811^{+0.015}_{-0.012}$ and $Ω_{\rm m} = 0.263^{+0.023}_{-0.030}$, results consistent with primary CMB analyses from Planck and P-ACT. We find evidence for reduced thermal gas pressure in dark matter halos with masses $M < 10^{14} \, M_{\odot}/h$, supporting predictions of enhanced feedback from active galactic nuclei on gas thermodynamics. A comparison of the inferred matter power suppression reveals a $2-4σ$ tension with hydrodynamical simulations that implement mild baryonic feedback, as our constraints prefer a stronger suppression. Finally, we investigate biases from cosmic infrared background leakage in the tSZ-shear cross-correlation measurements, employing mitigation techniques to ensure a robust inference. Our code is publicly available on GitHub.
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Submitted 9 June, 2025;
originally announced June 2025.
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A systematic study of projection biases in the Weak Lensing analysis of cosmic shear and the combination of galaxy clustering and galaxy-galaxy lensing
Authors:
P. R. V. Chintalapati,
G. Gutierrez,
M. H. L. S. Wang
Abstract:
This paper presents the results of a systematic study of projection biases in the Weak Lensing analysis of cosmic shear and the combination of galaxy clustering and galaxy-galaxy lensing using data collected during the first-year of running the Dark Energy Survey experiment. The study uses $Λ$CDM as the cosmological model and two-point correlation functions for the WL analysis. The results in this…
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This paper presents the results of a systematic study of projection biases in the Weak Lensing analysis of cosmic shear and the combination of galaxy clustering and galaxy-galaxy lensing using data collected during the first-year of running the Dark Energy Survey experiment. The study uses $Λ$CDM as the cosmological model and two-point correlation functions for the WL analysis. The results in this paper show that, independent of the WL analysis, projection biases of more than $1σ$ exist, and are a function of the position of the true values of the parameters $h$, $n_{s}$, $Ω_{b}$, and $Ω_νh^{2}$ with respect to their prior probabilities. For cosmic shear, and the combination of galaxy clustering and galaxy-galaxy lensing, this study shows that the coverage probability of the $68.27\%$ credible intervals ranges from as high as $93\%$ to as low as $16\%$, and that these credible intervals are inflated, on average, by $29\%$ for cosmic shear and $20\%$ for the combination of galaxy clustering and galaxy-galaxy lensing. The results of the study also show that, in six out of nine tested cases, the reduction in error bars obtained by transforming credible intervals into confidence intervals is equivalent to an increase in the amount of data by a factor of three.
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Submitted 12 March, 2024;
originally announced March 2024.
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Constraining the Baryonic Feedback with Cosmic Shear Using the DES Year-3 Small-Scale Measurements
Authors:
A. Chen,
G. Aricò,
D. Huterer,
R. Angulo,
N. Weaverdyck,
O. Friedrich,
L. F. Secco,
C. Hernández-Monteagudo,
A. Alarcon,
O. Alves,
A. Amon,
F. Andrade-Oliveira,
E. Baxter,
K. Bechtol,
M. R. Becker,
G. M. Bernstein,
J. Blazek,
A. Brandao-Souza,
S. L. Bridle,
H. Camacho,
A. Campos,
A. Carnero Rosell,
M. Carrasco Kind,
R. Cawthon,
C. Chang
, et al. (117 additional authors not shown)
Abstract:
We use the small scales of the Dark Energy Survey (DES) Year-3 cosmic shear measurements, which are excluded from the DES Year-3 cosmological analysis, to constrain the baryonic feedback. To model the baryonic feedback, we adopt a baryonic correction model and use the numerical package \texttt{Baccoemu} to accelerate the evaluation of the baryonic nonlinear matter power spectrum. We design our ana…
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We use the small scales of the Dark Energy Survey (DES) Year-3 cosmic shear measurements, which are excluded from the DES Year-3 cosmological analysis, to constrain the baryonic feedback. To model the baryonic feedback, we adopt a baryonic correction model and use the numerical package \texttt{Baccoemu} to accelerate the evaluation of the baryonic nonlinear matter power spectrum. We design our analysis pipeline to focus on the constraints of the baryonic suppression effects, utilizing the implication given by a principal component analysis on the Fisher forecasts. Our constraint on the baryonic effects can then be used to better model and ameliorate the effects of baryons in producing cosmological constraints from the next generation large-scale structure surveys. We detect the baryonic suppression on the cosmic shear measurements with a $\sim 2 σ$ significance. The characteristic halo mass for which half of the gas is ejected by baryonic feedback is constrained to be $M_c > 10^{13.2} h^{-1} M_{\odot}$ (95\% C.L.). The best-fit baryonic suppression is $\sim 5\%$ at $k=1.0 {\rm Mpc}\ h^{-1}$ and $\sim 15\%$ at $k=5.0 {\rm Mpc} \ h^{-1}$. Our findings are robust with respect to the assumptions about the cosmological parameters, specifics of the baryonic model, and intrinsic alignments.
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Submitted 17 June, 2022;
originally announced June 2022.
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A Systematic Study of Projection Biases in Weak Lensing Analysis
Authors:
P. R. V. Chintalapati,
G. Gutierrez,
M. H. L. S. Wang
Abstract:
We present a systematic study of projection biases in the weak lensing analysis of the first year of data from the Dark Energy Survey (DES) experiment. In the analysis we used a $Λ$CDM model and three two-point correlation functions. We show that these biases are a consequence of projecting, or marginalizing, over parameters like $h$, $Ω_b$, $n_s$ and $Ω_νh^2$ that are both poorly constrained and…
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We present a systematic study of projection biases in the weak lensing analysis of the first year of data from the Dark Energy Survey (DES) experiment. In the analysis we used a $Λ$CDM model and three two-point correlation functions. We show that these biases are a consequence of projecting, or marginalizing, over parameters like $h$, $Ω_b$, $n_s$ and $Ω_νh^2$ that are both poorly constrained and correlated with the parameters of interest like $Ω_m$, $σ_8$ and $S_8$. Covering the relevant parameter space we show that the projection biases are a function of where the true values of the poorly constrained parameters lie with respect to the parameter priors. For example, biases in the position of the posteriors can exceed the 1.5$σ$ level if the true values of $h$ and $n_s$ are close to the top of the prior's range and the true values of $Ω_b$ and $Ω_νh^2$ are close to the bottom of the range of their priors. We also show that in some cases the 1D credible intervals can be over-specified by as much as 30% and coverage can be as low as 27%. Finally we estimate these projection biases for the analysis of three and six years worth of DES data.
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Submitted 15 October, 2021; v1 submitted 25 August, 2021;
originally announced August 2021.
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Dark Energy Survey Year 3 Results: Multi-Probe Modeling Strategy and Validation
Authors:
E. Krause,
X. Fang,
S. Pandey,
L. F. Secco,
O. Alves,
H. Huang,
J. Blazek,
J. Prat,
J. Zuntz,
T. F. Eifler,
N. MacCrann,
J. DeRose,
M. Crocce,
A. Porredon,
B. Jain,
M. A. Troxel,
S. Dodelson,
D. Huterer,
A. R. Liddle,
C. D. Leonard,
A. Amon,
A. Chen,
J. Elvin-Poole,
A. Ferté,
J. Muir
, et al. (99 additional authors not shown)
Abstract:
This paper details the modeling pipeline and validates the baseline analysis choices of the DES Year 3 joint analysis of galaxy clustering and weak lensing (a so-called "3$\times$2pt" analysis). These analysis choices include the specific combination of cosmological probes, priors on cosmological and systematics parameters, model parameterizations for systematic effects and related approximations,…
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This paper details the modeling pipeline and validates the baseline analysis choices of the DES Year 3 joint analysis of galaxy clustering and weak lensing (a so-called "3$\times$2pt" analysis). These analysis choices include the specific combination of cosmological probes, priors on cosmological and systematics parameters, model parameterizations for systematic effects and related approximations, and angular scales where the model assumptions are validated. We run a large number of simulated likelihood analyses using synthetic data vectors to test the robustness of our baseline analysis. We demonstrate that the DES Year 3 modeling pipeline, including the calibrated scale cuts, is sufficiently accurate relative to the constraining power of the DES Year 3 analyses. Our systematics mitigation strategy accounts for astrophysical systematics, such as galaxy bias, intrinsic alignments, source and lens magnification, baryonic effects, and source clustering, as well as for uncertainties in modeling the matter power spectrum, reduced shear, and estimator effects. We further demonstrate excellent agreement between two independently-developed modeling pipelines, and thus rule out any residual uncertainties due to the numerical implementation.
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Submitted 27 May, 2021;
originally announced May 2021.
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Dark Energy Survey Year 3 results: Cosmological constraints from galaxy clustering and galaxy-galaxy lensing using the MagLim lens sample
Authors:
A. Porredon,
M. Crocce,
J. Elvin-Poole,
R. Cawthon,
G. Giannini,
J. De Vicente,
A. Carnero Rosell,
I. Ferrero,
E. Krause,
X. Fang,
J. Prat,
M. Rodriguez-Monroy,
S. Pandey,
A. Pocino,
F. J. Castander,
A. Choi,
A. Amon,
I. Tutusaus,
S. Dodelson,
I. Sevilla-Noarbe,
P. Fosalba,
E. Gaztanaga,
A. Alarcon,
O. Alves,
F. Andrade-Oliveira
, et al. (119 additional authors not shown)
Abstract:
Two of the most sensitive probes of the large scale structure of the universe are the clustering of galaxies and the tangential shear of background galaxy shapes produced by those foreground galaxies, so-called galaxy-galaxy lensing. Combining the measurements of these two two-point functions leads to cosmological constraints that are independent of the galaxy bias factor. The optimal choice of fo…
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Two of the most sensitive probes of the large scale structure of the universe are the clustering of galaxies and the tangential shear of background galaxy shapes produced by those foreground galaxies, so-called galaxy-galaxy lensing. Combining the measurements of these two two-point functions leads to cosmological constraints that are independent of the galaxy bias factor. The optimal choice of foreground, or lens, galaxies is governed by the joint, but conflicting requirements to obtain accurate redshift information and large statistics. We present cosmological results from the full 5000 sq. deg. of the Dark Energy Survey first three years of observations (Y3) combining those two-point functions, using for the first time a magnitude-limited lens sample (MagLim) of 11 million galaxies especially selected to optimize such combination, and 100 million background shapes. We consider two cosmological models, flat $Λ$CDM and $w$CDM. In $Λ$CDM we obtain for the matter density $Ω_m = 0.320^{+0.041}_{-0.034}$ and for the clustering amplitude $S_8 = 0.778^{+0.037}_{-0.031}$, at 68% C.L. The latter is only 1$σ$ smaller than the prediction in this model informed by measurements of the cosmic microwave background by the Planck satellite. In $w$CDM we find $Ω_m = 0.32^{+0.044}_{-0.046}$, $S_8=0.777^{+0.049}_{-0.051}$, and dark energy equation of state $w=-1.031^{+0.218}_{-0.379}$. We find that including smaller scales while marginalizing over non-linear galaxy bias improves the constraining power in the $Ω_m-S_8$ plane by $31$% and in the $Ω_m-w$ plane by $41$% while yielding consistent cosmological parameters from those in the linear bias case. These results are combined with those from cosmic shear in a companion paper to present full DES-Y3 constraints from the three two-point functions (3x2pt).
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Submitted 21 December, 2022; v1 submitted 27 May, 2021;
originally announced May 2021.
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Dark Energy Survey Year 3 Results: Constraints on cosmological parameters and galaxy bias models from galaxy clustering and galaxy-galaxy lensing using the redMaGiC sample
Authors:
S. Pandey,
E. Krause,
J. DeRose,
N. MacCrann,
B. Jain,
M. Crocce,
J. Blazek,
A. Choi,
H. Huang,
C. To,
X. Fang,
J. Elvin-Poole,
J. Prat,
A. Porredon,
L. F. Secco,
M. Rodriguez-Monroy,
N. Weaverdyck,
Y. Park,
M. Raveri,
E. Rozo,
E. S. Rykoff,
G. M. Bernstein,
C. Sánchez,
M. Jarvis,
M. A. Troxel
, et al. (116 additional authors not shown)
Abstract:
We constrain cosmological and galaxy-bias parameters using the combination of galaxy clustering and galaxy-galaxy lensing measurements from the Dark Energy Survey Year-3 data. We describe our modeling framework, and choice of scales analyzed, validating their robustness to theoretical uncertainties in small-scale clustering by analyzing simulated data. Using a linear galaxy bias model and redMaGiC…
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We constrain cosmological and galaxy-bias parameters using the combination of galaxy clustering and galaxy-galaxy lensing measurements from the Dark Energy Survey Year-3 data. We describe our modeling framework, and choice of scales analyzed, validating their robustness to theoretical uncertainties in small-scale clustering by analyzing simulated data. Using a linear galaxy bias model and redMaGiC galaxy sample, we obtain constraints on the matter density to be $Ω_{\rm m} = 0.325^{+0.033}_{-0.034}$. We also implement a non-linear galaxy bias model to probe smaller scales that includes parameterization based on hybrid perturbation theory and find that it leads to a 17% gain in cosmological constraining power. We perform robustness tests of our methodology pipeline and demonstrate the stability of the constraints to changes in the theoretical model. Using the redMaGiC galaxy sample as foreground lens galaxies, we find the galaxy clustering and galaxy-galaxy lensing measurements to exhibit significant signals akin to de-correlation between galaxies and mass on large scales, which is not expected in any current models. This likely systematic measurement error biases our constraints on galaxy bias and the $S_8$ parameter. We find that a scale-, redshift- and sky-area-independent phenomenological de-correlation parameter can effectively capture the impact of this systematic error. We trace the source of this de-correlation to a color-dependent photometric issue and minimize its impact on our result by changing the selection criteria of redMaGiC galaxies. Using this new sample, our constraints on the $S_8$ parameter are consistent with previous studies, and we find a small shift in the $Ω_{\rm m}$ constraints compared to the fiducial redMaGiC sample. We constrain the mean host halo mass of the redMaGiC galaxies in this new sample to be approximately $1.6 \times 10^{13} M_{\odot}/h$.
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Submitted 25 September, 2022; v1 submitted 27 May, 2021;
originally announced May 2021.
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Dark Energy Survey Year 3 Results: Cosmology from Cosmic Shear and Robustness to Modeling Uncertainty
Authors:
L. F. Secco,
S. Samuroff,
E. Krause,
B. Jain,
J. Blazek,
M. Raveri,
A. Campos,
A. Amon,
A. Chen,
C. Doux,
A. Choi,
D. Gruen,
G. M. Bernstein,
C. Chang,
J. DeRose,
J. Myles,
A. Ferté,
P. Lemos,
D. Huterer,
J. Prat,
M. A. Troxel,
N. MacCrann,
A. R. Liddle,
T. Kacprzak,
X. Fang
, et al. (129 additional authors not shown)
Abstract:
This work and its companion paper, Amon et al. (2021), present cosmic shear measurements and cosmological constraints from over 100 million source galaxies in the Dark Energy Survey (DES) Year 3 data. We constrain the lensing amplitude parameter $S_8\equivσ_8\sqrt{Ω_\textrm{m}/0.3}$ at the 3% level in $Λ$CDM: $S_8=0.759^{+0.025}_{-0.023}$ (68% CL). Our constraint is at the 2% level when using angu…
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This work and its companion paper, Amon et al. (2021), present cosmic shear measurements and cosmological constraints from over 100 million source galaxies in the Dark Energy Survey (DES) Year 3 data. We constrain the lensing amplitude parameter $S_8\equivσ_8\sqrt{Ω_\textrm{m}/0.3}$ at the 3% level in $Λ$CDM: $S_8=0.759^{+0.025}_{-0.023}$ (68% CL). Our constraint is at the 2% level when using angular scale cuts that are optimized for the $Λ$CDM analysis: $S_8=0.772^{+0.018}_{-0.017}$ (68% CL). With cosmic shear alone, we find no statistically significant constraint on the dark energy equation-of-state parameter at our present statistical power. We carry out our analysis blind, and compare our measurement with constraints from two other contemporary weak-lensing experiments: the Kilo-Degree Survey (KiDS) and Hyper-Suprime Camera Subaru Strategic Program (HSC). We additionally quantify the agreement between our data and external constraints from the Cosmic Microwave Background (CMB). Our DES Y3 result under the assumption of $Λ$CDM is found to be in statistical agreement with Planck 2018, although favors a lower $S_8$ than the CMB-inferred value by $2.3σ$ (a $p$-value of 0.02). This paper explores the robustness of these cosmic shear results to modeling of intrinsic alignments, the matter power spectrum and baryonic physics. We additionally explore the statistical preference of our data for intrinsic alignment models of different complexity. The fiducial cosmic shear model is tested using synthetic data, and we report no biases greater than 0.3$σ$ in the plane of $S_8\timesΩ_\textrm{m}$ caused by uncertainties in the theoretical models.
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Submitted 13 January, 2022; v1 submitted 27 May, 2021;
originally announced May 2021.
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Dark Energy Survey Year 3 Results: Cosmology from Cosmic Shear and Robustness to Data Calibration
Authors:
A. Amon,
D. Gruen,
M. A. Troxel,
N. MacCrann,
S. Dodelson,
A. Choi,
C. Doux,
L. F. Secco,
S. Samuroff,
E. Krause,
J. Cordero,
J. Myles,
J. DeRose,
R. H. Wechsler,
M. Gatti,
A. Navarro-Alsina,
G. M. Bernstein,
B. Jain,
J. Blazek,
A. Alarcon,
A. Ferté,
M. Raveri,
P. Lemos,
A. Campos,
J. Prat
, et al. (123 additional authors not shown)
Abstract:
This work, together with its companion paper, Secco and Samuroff et al. (2021), presents the Dark Energy Survey Year 3 cosmic shear measurements and cosmological constraints based on an analysis of over 100 million source galaxies. With the data spanning 4143 deg$^2$ on the sky, divided into four redshift bins, we produce the highest significance measurement of cosmic shear to date, with a signal-…
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This work, together with its companion paper, Secco and Samuroff et al. (2021), presents the Dark Energy Survey Year 3 cosmic shear measurements and cosmological constraints based on an analysis of over 100 million source galaxies. With the data spanning 4143 deg$^2$ on the sky, divided into four redshift bins, we produce the highest significance measurement of cosmic shear to date, with a signal-to-noise of 40. We conduct a blind analysis in the context of the $Λ$CDM model and find a 3% constraint of the clustering amplitude, $S_8\equiv σ_8 (Ω_{\rm m}/0.3)^{0.5} = 0.759^{+0.025}_{-0.023}$. A $Λ$CDM-Optimized analysis, which safely includes smaller scale information, yields a 2% precision measurement of $S_8= 0.772^{+0.018}_{-0.017}$ that is consistent with the fiducial case. The two low-redshift measurements are statistically consistent with the Planck Cosmic Microwave Background result, however, both recovered $S_8$ values are lower than the high-redshift prediction by $2.3σ$ and $2.1σ$ ($p$-values of 0.02 and 0.05), respectively. The measurements are shown to be internally consistent across redshift bins, angular scales and correlation functions. The analysis is demonstrated to be robust to calibration systematics, with the $S_8$ posterior consistent when varying the choice of redshift calibration sample, the modeling of redshift uncertainty and methodology. Similarly, we find that the corrections included to account for the blending of galaxies shifts our best-fit $S_8$ by $0.5σ$ without incurring a substantial increase in uncertainty. We examine the limiting factors for the precision of the cosmological constraints and find observational systematics to be subdominant to the modeling of astrophysics. Specifically, we identify the uncertainties in modeling baryonic effects and intrinsic alignments as the limiting systematics.
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Submitted 29 September, 2022; v1 submitted 27 May, 2021;
originally announced May 2021.