Showing 1–50 of 465 results for author: Rieke, G

Determining Total Infrared Luminosities from Submm Measurements of High Redshift Galaxies

Authors: Maria Emilia De Rossi, George H. Rieke, Christina C. Williams, Volker Bromm, Jianwei Lyu, Meredith A. Stone, Yang Sun, Christopher N. A. Willmer, Yongda Zhu

Abstract: Determining total infrared luminosities for very high redshift galaxies is important to estimate the rate of star formation in heavily dust-embedded environments. It is also challenging because the most sensitive far infrared observatory, Herschel, was limited in sensitivity and its deepest measurements are subject to confusion noise. Thus, these determinations largely depend on ALMA, observing in… ▽ More Determining total infrared luminosities for very high redshift galaxies is important to estimate the rate of star formation in heavily dust-embedded environments. It is also challenging because the most sensitive far infrared observatory, Herschel, was limited in sensitivity and its deepest measurements are subject to confusion noise. Thus, these determinations largely depend on ALMA, observing in the mm- and/or submm-wavelengths, which sample only the long-wavelength part of the spectral energy distributions (SEDs). Luminosities are conventionally estimated with modified blackbody fits to these measurements, but do not include the emission in the mid-infrared by warmer dust; there is evidence that this mid-IR component may be relatively strong in very high-redshift galaxies compared with local ones. A correction factor must be applied to the modified black body luminosities to derive the total infrared luminosity. We study infrared SEDs using simulations tuned to galactic conditions typical of high-z galaxies. We find that the different behaviors of infrared SEDs are dominated by a single key physical parameter, the luminosity density. This allows us to estimate the corrections for the missing mid-infrared luminosity in a general way. We find that a factor of ~ 1.6 - 1.7 (0.2 dex) is appropriate in most circumstances, with a larger factor of ~ 1.75 - 1.85 (~ 0.25 dex) up to 2 (0.3 dex) necessary for high redshift (z > 4) galaxies at the highest luminosities, > 10^{12} Lsun. These corrections are needed to estimate star formation rates based on total infrared luminosity. △ Less

Submitted 30 July, 2026; originally announced July 2026.

Comments: accepted by ApJ

JWST/NIRCam Imaging of Young Stellar Objects. IV. Detailed Imaging of the Protoplanetary Disk around TW Hya

Authors: Yu-Chia Lin, Jarron Leisenring, Schuyler G. Wolff, Justin Hom, Kellen Lawson, Ewan S. Douglas, George Rieke, Gabriele Cugno, John Debes, Ruobing Dong, Doug Johnstone, Camryn Mullin, Taylor L. Tobin, Kevin R. Wagner, Thomas P. Greene, Michael R. Meyer, Marcia Rieke

Abstract: As the nearest protoplanetary disk to Earth ($d = 60.14$ pc), TW Hya is one of the most studied protoplanetary disks and a critical benchmark for testing planet formation theories. We present high-contrast coronagraphic imaging of the TW Hya disk from JWST/NIRCam across four filters (F187N, F200W, F356W, and F444W). We detect the disk's scattered-light emission in F200W, F356W, and F444W. An ellip… ▽ More As the nearest protoplanetary disk to Earth ($d = 60.14$ pc), TW Hya is one of the most studied protoplanetary disks and a critical benchmark for testing planet formation theories. We present high-contrast coronagraphic imaging of the TW Hya disk from JWST/NIRCam across four filters (F187N, F200W, F356W, and F444W). We detect the disk's scattered-light emission in F200W, F356W, and F444W. An elliptical fit to the disk image yields an average inclination of $i = 8.74^{+1.03}_{-0.94}$ degrees and a position angle of $\mathrm{PA} = 75.62^{+7.86}_{-6.56}$ degrees. We find tentative evidence for radial variations in these parameters, a trend consistent with a disk warp. Our companion search yields no new detections, placing the lowest mass limits yet on companions that might be responsible for carving out the dust gap. Assuming no local extinction and a system age of 10 Myr, the F444W data are sensitive to masses down to $\sim 0.4\,M_{\rm Jup}$ at separations of $1$ arcsec ($\sim 60$ AU). Accounting for local disk extinction analogous to the AS 209 system, our limits reach sub-Jupiter masses beyond $2$ arcsec. Furthermore, our analysis provides a detailed view of a previously detected feature in the outer disk at $\sim 120$ AU, confirming its morphology as a distinct bifurcation structure. This feature may indicate the presence of complex substructures arising from dynamical planet-disk interactions. These results demonstrate JWST's ability to characterize the architecture of protoplanetary disks and constrain the properties of forming worlds. △ Less

Submitted 19 August, 2026; v1 submitted 27 July, 2026; originally announced July 2026.

Comments: 31 pages, 14 figures, 7 tables. Accepted for publication in The Astronomical Journal (AJ)

PhotoIFU: NIRCam as a Photometric Integral Field Unit for Mapping Feedback in Galaxies

Authors: Yongda Zhu, Marcia J. Rieke, Courtney Carreira, Yang Sun, Zhiyuan Ji, Jianwei Lyu, Christina C. Williams, Stacey Alberts, Feng Yuan, Yuxuan Zou, Yurina Nakazato, Andrew J. Bunker, Sandro Tacchella, Fengwu Sun, George H. Rieke, Eiichi Egami, Jacopo Chevallard, Kevin Hainline, Zheng Ma, Pablo G. Pérez-González, Pierluigi Rinaldi, Bruno Rodríguez Del Pino, Tristen Shields, Meredith Stone, Christopher N. A. Willmer , et al. (3 additional authors not shown)

Abstract: We present PhotoIFU, a workflow that uses deep multi-band imaging as a low-resolution photometric integral field unit. Applied to PSF-matched JWST/NIRCam imaging, PhotoIFU treats each spatial pixel as a coarse SED element and fits the pixel SEDs with Prospector to map resolved stellar-population and ISM-related properties. We apply this approach to three galaxies at $z=1.3$--3.7 in JADES: two syst… ▽ More We present PhotoIFU, a workflow that uses deep multi-band imaging as a low-resolution photometric integral field unit. Applied to PSF-matched JWST/NIRCam imaging, PhotoIFU treats each spatial pixel as a coarse SED element and fits the pixel SEDs with Prospector to map resolved stellar-population and ISM-related properties. We apply this approach to three galaxies at $z=1.3$--3.7 in JADES: two systems with extended ionized line emission and one post-starburst galaxy with an exceptionally strong neutral outflow. Pixel-by-pixel SED fitting gives maps of stellar-mass surface density, specific star formation rate, dust attenuation, gas-phase metallicity, and recent star-formation history. We find that regions selected from the extended-emission or outflow geometry occupy distinct parts of the resolved SED-property distribution compared with the full host. In the systems with extended ionized emission, these regions are generally less dusty, consistent with ionized emission being observed along dust-poor, low-column-density pathways through the host. In the neutral-outflow system, the selected regions show enhanced recent star formation, suggesting that compact rejuvenation may mark the aftermath of an earlier energetic phase. These results show that galactic outflows and extended emission-line structures can be spatially associated with measurable differences in resolved host-galaxy stellar populations and ISM-related properties. PhotoIFU provides an imaging-based method for resolved SED mapping of feedback-related structures in larger galaxy samples where full spectroscopic integral-field mapping is unavailable. △ Less

Submitted 24 July, 2026; originally announced July 2026.

Comments: 22 pages. Submitted to ApJ. The code will be made publicly available

A quasar hatching from a buried red phase at z = 3.7

Authors: Zheng Ma, Yongda Zhu, Zhiyuan Ji, Eiichi Egami, Marcia J. Rieke, Xiaohui Fan, Jianwei Lyu, George H. Rieke, Fengwu Sun, Yang Sun, George D. Becker, Andrew J. Bunker, Francesco D'Eugenio, Xiangyu Jin, Ignas Juodžbalis, Weizhe Liu, Roberto Maiolino, Pierluigi Rinaldi, Feige Wang, Christopher N. A. Willmer, Yunjing Wu, Jinyi Yang, Junyu Zhang, Peixin Zhu

Abstract: We present JADES-GS 209777, previously cataloged as CANDELS J033238.02-274626.2, hereafter "the Hatchling," a red quasar at $z=3.711$. While the source has been reported in earlier deep-field catalogs, our multiwavelength analysis reveals a visible active nucleus still embedded in a dense gas- and dust-rich environment. Red quasar continua are often attributed to dust attenuation, including non-st… ▽ More We present JADES-GS 209777, previously cataloged as CANDELS J033238.02-274626.2, hereafter "the Hatchling," a red quasar at $z=3.711$. While the source has been reported in earlier deep-field catalogs, our multiwavelength analysis reveals a visible active nucleus still embedded in a dense gas- and dust-rich environment. Red quasar continua are often attributed to dust attenuation, including non-standard extinction curves, but the highly comprehensive multiwavelength data for this source provide direct constraints on the material being cleared. Using JWST/NIRSpec, NIRCam, MIRI, HST, MUSE, Chandra, ALMA, and VLA data, we detect broad emission lines and strong X-ray emission, showing that the active nucleus is at least partially exposed. We also detect H$α$ and He I absorption, indicating dense gas close to the nucleus. Kinematically disturbed O I, Mg II, Na D, and [O III] features, together with extended Ly$α$ emission over $\gtrsim 20$ kpc, further show that multiphase gas is being accelerated from the nuclear region into the host-galaxy environment. The ALMA detection reveals strong dust emission, with the inferred infrared luminosity placing the system in the ULIRG regime. The continuum is red and sharply declining toward the rest-frame UV, resembling compact red AGNs, and may reflect extreme dust attenuation, gas reprocessing, possible BAL-like absorption, or a combination of these effects. Regardless of which mechanism dominates the continuum shape, the line diagnostics show that the visible nucleus remains partially obscured by nearby material. The Hatchling therefore represents a unique opportunity to explore a poorly known transition phase in which feedback is likely clearing an enshrouded quasar and allowing it to emerge toward a more unobscured active nucleus. △ Less

Submitted 24 July, 2026; originally announced July 2026.

Comments: 26 pages, 5 main figures, and 10 Extended Data figures. Submitted, comments are welcome

Extreme Debris Disks: Insights into Violent Collisions in Planet Formation and Destruction

Authors: Kate Y. L. Su, Attila Moor, Agnes Kospal, George H. Rieke, Antranik A. Sefilian, Renu Malhotra, Ilaria Pascucci, Alan P. Jackson, Peter Abraham, Nicholas P. Ballering

Abstract: Debris disks are dusty structures around mature stars, primarily identified by infrared excesses in the stellar spectra. A subset, known as extreme debris disks (EDDs), exhibits stochastic infrared variability, believed to result from large-scale violent collisions that contribute to the formation or destruction of rocky planetary bodies. We analyze JWST and Spitzer mid-infrared spectra for 21 EDD… ▽ More Debris disks are dusty structures around mature stars, primarily identified by infrared excesses in the stellar spectra. A subset, known as extreme debris disks (EDDs), exhibits stochastic infrared variability, believed to result from large-scale violent collisions that contribute to the formation or destruction of rocky planetary bodies. We analyze JWST and Spitzer mid-infrared spectra for 21 EDDs to investigate the connection between impact-produced dust mineralogy and the age and dynamical state of these systems during various stages of planet formation and evolution. Our findings indicate that EDDs contain significantly more optically thin, small dust grains compared to those typically seen in protoplanetary and debris disks. Predominantly submicron in size, these grains are thermally altered, as shown by their high levels of silica and crystalline silicate composition. Along with stochastic infrared variability, these features define EDDs as a subclass of debris systems where dust is generated from large collisions between Moon- and Mars-sized bodies. Our results not only provide diagnostic information about the physical conditions of violent events during terrestrial planet formation, aiding in differentiating the complex outcomes of these impacts, but also offer a potential marker for identifying planetary systems experiencing dynamical instability. △ Less

Submitted 7 July, 2026; originally announced July 2026.

Comments: accepted for publication in ApJ

Compact Core, Extended Reach: A Bipolar kpc-Scale Elongation in a Little Red Dot at $z \approx 5.5$

Authors: Zhiyuan Ji, Yang Sun, Mauro Giavalisco, Yongda Zhu, George H. Rieke, Christina C. Williams, Michael V. Maseda, Jianwei Lyu, Marcia Rieke, Sandro Tacchella

Abstract: Little Red Dots (LRDs) appear extremely compact at rest-frame optical wavelengths, yet many show extended rest-frame UV morphology revealing more complex internal structure. We present a combined analysis of VLT/MUSE rest-frame UV integral-field spectroscopy and continuum-subtracted [O III], H$β$, and H$α$+[N II] emission-line maps from JWST/NIRCam imaging at sub-kpc resolution for LRD-204851 at… ▽ More Little Red Dots (LRDs) appear extremely compact at rest-frame optical wavelengths, yet many show extended rest-frame UV morphology revealing more complex internal structure. We present a combined analysis of VLT/MUSE rest-frame UV integral-field spectroscopy and continuum-subtracted [O III], H$β$, and H$α$+[N II] emission-line maps from JWST/NIRCam imaging at sub-kpc resolution for LRD-204851 at $z=5.482$ in GOODS-S. We find that LRD-204851 hosts a remarkably thin, bipolar, elongated structure passing through the optical continuum centroid and extending several kpc on either side, traced by both the UV continuum and the rest-frame optical emission lines, with a bright [O III] clump-like structure $\sim$2 kpc to the south-east of the centroid. The MUSE observations reveal a double-peaked Ly$α$ profile, with a broad and bright near-systemic red peak and a relatively faint peak blueshifted by $\sim$430 km s$^{-1}$, accompanied by a tentative N V $λ1238$ detection at similar velocity. In narrow-band imaging extracted from the MUSE IFU cube, both the blue Ly$α$ peak and the tentative N V emission lean toward this same south-eastern direction. Independently, radiative-transfer modeling of the integrated Ly$α$ profile favors a biconical low-column-density cavity in a dense, slowly expanding neutral envelope, in support of the bipolar geometry traced by the line maps. Together, these results suggest that the elongated emission of LRD-204851 is connected to radiation and/or gas flow from its central engine through a low-column-density channel with a small opening angle that may trace either a slow outflow or a quasi-static ionization cone. LRD-204851 is one of the first LRDs where the central engine's impact on its host galaxy is potentially directly observable on kpc scales. △ Less

Submitted 16 June, 2026; originally announced June 2026.

Comments: 15 pages, 9 figures, submitted to ApJL

Through the Veil: Ly$α$ Illuminates the Host Galaxies of Little Red Dots

Authors: Zhiyuan Ji, Yang Sun, Mauro Giavalisco, Anna de Graaff, Christina C. Williams, Yongda Zhu, George H. Rieke, Marcia Rieke

Abstract: Little Red Dots (LRDs) are enigmatic, compact red sources ubiquitous in JWST deep fields whose physical nature remains elusive. As one of the most sensitive tracers of neutral hydrogen in galaxy environments, Ly$α$ is uniquely positioned to probe the gaseous structures proposed to explain LRDs' unusual properties. We present a systematic study of Ly$α$ emission in LRDs, using a sample of 110 spect… ▽ More Little Red Dots (LRDs) are enigmatic, compact red sources ubiquitous in JWST deep fields whose physical nature remains elusive. As one of the most sensitive tracers of neutral hydrogen in galaxy environments, Ly$α$ is uniquely positioned to probe the gaseous structures proposed to explain LRDs' unusual properties. We present a systematic study of Ly$α$ emission in LRDs, using a sample of 110 spectroscopically confirmed LRDs at $z \geq 4$ from the A. de Graaff et al. (2025) catalog, all with NIRSpec/PRISM coverage of the Ly$α$ line. We detect Ly$α$ at signal-to-noise S/N $\geq$ 3 in 32 LRDs, finding Ly$α$ luminosities and the distribution of rest-frame equivalent widths consistent with normal star-forming galaxies at comparable redshifts. Yet the Ly$α$/H$α$ ratios fall systematically below those of star-forming galaxies, and the Ly$α$ luminosity tracks [O III] luminosity more closely than [O III] equivalent width, together suggesting that Ly$α$ is primarily associated with the host-scale component rather than the compact component responsible for the broad Balmer lines and red continuum. For 13 LRDs at $z \gtrsim 5.5$, we construct continuum-subtracted Ly$α$ maps using broadband imaging from HST/ACS or JWST/NIRCam, revealing spatially extended, asymmetric, and often offset emission relative to the rest-optical light, consistent with resonant scattering through clumpy, anisotropic gas commonly observed in high-redshift Ly$α$ emitters. These results support a two-component picture in which the compact rest-optical source is embedded within a more extended host-galaxy environment whose interstellar and circumgalactic gas shapes Ly$α$ escape and spatial redistribution. Ly$α$ opens a new window into the relation between the compact red component, the host galaxy, and the surrounding gas in LRDs. △ Less

Submitted 8 June, 2026; originally announced June 2026.

Comments: 27 pages, 17 figures, submitted to ApJ

Early metal-enriched baryon cycling before the midpoint of cosmic reionization

Authors: Yongda Zhu, Zhiyuan Ji, George D. Becker, Jiani Ding, Eiichi Egami, Xiaohui Fan, Xiangyu Jin, Weizhe Liu, Jianwei Lyu, Zheng Ma, Suprabhas Narisetty, George H. Rieke, Yunjing Wu, Minghao Yue, Junyu Zhang, Marcia J. Rieke

Abstract: Models predict that chemical enrichment and gas redistribution should begin rapidly once star formation starts, but direct constraints at the earliest epochs have been scarce. Here we show that metal-enriched gas in multiple ionic phases was already present around galaxies before the midpoint of cosmic reionization. Using JWST/NIRSpec rest-frame ultraviolet spectroscopy from SPURS, we detect blues… ▽ More Models predict that chemical enrichment and gas redistribution should begin rapidly once star formation starts, but direct constraints at the earliest epochs have been scarce. Here we show that metal-enriched gas in multiple ionic phases was already present around galaxies before the midpoint of cosmic reionization. Using JWST/NIRSpec rest-frame ultraviolet spectroscopy from SPURS, we detect blueshifted metal absorption in three galaxies at $7.2<z<9.3$. The detected transitions span neutral, low-ionization, and high-ionization species, including O I, Si II, C II, Si IV, and C IV, with velocity offsets of $|Δv|\sim 50$--$250\,\mathrm{km\,s^{-1}}$ relative to nebular systemic redshifts. The ionic coexistence, overlapping velocity structure, and equivalent-width ratios are consistent with outflowing or otherwise kinematically disturbed galaxy-associated gas, implying rapid metal enrichment. These results show that key conditions for baryon cycling were established in at least a subset of luminous galaxies within the first several hundred million years of cosmic time, well before the completion of reionization. △ Less

Submitted 22 June, 2026; v1 submitted 22 April, 2026; originally announced April 2026.

Comments: Resubmitted to Nature Astronomy after addressing reviewers' comments and editorial requests

A Census of Na D-traced neutral ISM and outflows at $0.6<z<4$

Authors: Yang Sun, Zhiyuan Ji, Francesco D'Eugenio, Yongda Zhu, George H. Rieke, William M. Baker, Andrew J. Bunker, Stefano Carniani, Jakob M. Helton, Michele Perna, Pablo G. Pérez-González, Pierluigi Rinaldi, Hannah Übler, Christopher N. A. Willmer

Abstract: We present a statistical census of the Na D-traced neutral interstellar medium (ISM) and outflows in 309 galaxies at $0.6<z<4$ using JWST/NIRSpec medium-resolution grating spectroscopy from the SMILES, JADES, Blue Jay, and Aurora surveys. After subtracting the stellar continuum, we model the Na D $λλ5890, 5896$ Åand detect neutral ISM absorption in 76 galaxies. Of the Na D-traced ISM detections, 8… ▽ More We present a statistical census of the Na D-traced neutral interstellar medium (ISM) and outflows in 309 galaxies at $0.6<z<4$ using JWST/NIRSpec medium-resolution grating spectroscopy from the SMILES, JADES, Blue Jay, and Aurora surveys. After subtracting the stellar continuum, we model the Na D $λλ5890, 5896$ Åand detect neutral ISM absorption in 76 galaxies. Of the Na D-traced ISM detections, 85\% are found in massive galaxies ($\log(M_*/M_\odot)>10$), and only 15\% in lower-mass systems. In the massive regime, ISM absorption is seen in both star-forming and quiescent galaxies, whereas in lower-mass systems it is observed only in star-forming galaxies. In massive quiescent galaxies, Na D detectability appears linked to star formation history: it is preferentially detected in older systems with larger 4000 Åbreaks, as well as younger, rapidly quenching galaxies with strong Balmer absorption H$δ_A$. We identify Na D outflows in 26 galaxies, revealing a possible dichotomy in their driving mechanisms between star-forming and quiescent galaxies. In star-forming galaxies, outflow properties correlate with star-formation properties, consistent with a star-formation-driven origin. In quiescent galaxies, however, outflows are not associated with residual star formation and often require more energy than such star formation can provide. Together with the high AGN fraction among outflow-detected quiescent galaxies, this suggests that AGN dominate Na D-traced neutral outflows in cosmic noon quiescent systems. We further identify five quiescent galaxies with possible AGN fossil outflows, suggesting that AGN-driven outflows can persist beyond the active accretion phase and may help maintain quiescence. △ Less

Submitted 20 April, 2026; originally announced April 2026.

Comments: 32 pages, 18 figures, submitted to ApJ

Calibrating Photometric Mid-Infrared Star Formation Rates for JWST

Authors: Stacey Alberts, George H. Rieke, Irene Shivaei, Zhiyuan Ji, Pascal Oesch, Gabriel Brammer, Jakob M. Helton, Jianwei Lyu, Erica J. Nelson, Naveen Reddy, Pierluigi Rinaldi, Yang Sun, Katherine E. Whitaker, Christina C. Williams, Christopher N. A. Willmer, Stijn Wuyts

Abstract: The mid-infrared (IR) spectrum of galaxies has a long history as a valuable proxy for the dust-obscured star formation rate (SFR) in massive galaxies. Now, with JWST, we can explore the mid-IR's full potential as a SFR tracer over four orders of magnitude in total infrared luminosity (9<~log LIR/Lo<~13). First, combining the SMILES and FRESCO surveys, we evaluate MIRI photometry against the Pa-alp… ▽ More The mid-infrared (IR) spectrum of galaxies has a long history as a valuable proxy for the dust-obscured star formation rate (SFR) in massive galaxies. Now, with JWST, we can explore the mid-IR's full potential as a SFR tracer over four orders of magnitude in total infrared luminosity (9<~log LIR/Lo<~13). First, combining the SMILES and FRESCO surveys, we evaluate MIRI photometry against the Pa-alpha emission line - a gold standard SFR indicator - in Main Sequence (MS) galaxies at cosmic noon. We find the rest-frame 6-8um luminosity has a steeply superlinear relation with SFR(Pa-alpha) below ~8 Mo/yr, in contrast with the unity slope seen in coeval massive galaxies. We derive broken power-law SFR indicators from single-band MIRI photometry plus a representative dust template, with a scatter typical of IR SFRs (~0.2-0.3 dex). Despite the break in the mid-IR behavior and our simplifying assumption of a single dust SED, we next successfully formulate a UV+IR composite relation (scatter ~0.15 dex) under the usual assumption of energy balance. This implies that the rest-frame 6-8um primarily tracks the global dust-obscuration fraction - which decreases rapidly at log M*/Mo<~10 - rather than reflecting a deficit in PAH abundances at low mass. Our results thus support MIRI photometry as a robust SFR proxy at log M*/Mo>~9 up to z~3. Finally, extending to local and z>~1 ultraluminous infrared galaxies not represented in SMILES, we examine when Pa-alpha and the IR reliably track SFR in the bright regime. △ Less

Submitted 4 April, 2026; v1 submitted 1 April, 2026; originally announced April 2026.

Comments: 23 pages, 12 figures, 3 tables. Submitted to ApJ. Updated abstract, final version failed to upload due to network issues

JWST Reveals Two Overmassive Black Hole Candidates in Dwarf Galaxies at z $\approx$ 0.7: Pushing Black Hole Searches into the Dwarf-Galaxy Regime

Authors: E. Iani, P. Rinaldi, A. Torralba, J. Lyu, R. Navarro-Carrera, G. H. Rieke, F. Sun, C. Willott, Y. Zhu, A. Alonso-Herrero, M. Annunziatella, P. Bergamini, K. Caputi, M. Catone, L. Colina, R. Cooper, L. Costantin, A. Crespo Gómez, G. Desprez, C. Di Cesare, M. J. Hayes, I. Jermann, G. Kotiwale, I. Kramarenko, D. Langeroodi , et al. (13 additional authors not shown)

Abstract: We report the discovery and characterization of two compact galaxies, Pelias and Neleus, at z ~ 0.71 and z ~ 0.75, identified in MACS J0416.1-2403 and GOODS-North. Both exhibit unusual spectral energy distributions (SEDs), with very blue rest-frame UV-optical emission and a steep rise toward near- and mid-infrared wavelengths. JWST/NIRISS and JWST/NIRSpec spectroscopy show strong rest-frame optica… ▽ More We report the discovery and characterization of two compact galaxies, Pelias and Neleus, at z ~ 0.71 and z ~ 0.75, identified in MACS J0416.1-2403 and GOODS-North. Both exhibit unusual spectral energy distributions (SEDs), with very blue rest-frame UV-optical emission and a steep rise toward near- and mid-infrared wavelengths. JWST/NIRISS and JWST/NIRSpec spectroscopy show strong rest-frame optical lines ([O III] 4959,5007 and Halpha) with extreme equivalent widths (>= 1000 Angstrom), indicating young burst-dominated populations with low metallicities (Z ~ 0.1-0.4 Zsun), low dust attenuation (Av ~ 0.2 mag), and stellar masses of Mstar ~ 10^7 Msun. Nonetheless, JWST/MIRI photometry reveals a strong mid-infrared excess that cannot be explained by stellar populations or star-formation-heated dust alone, requiring a hot-dust component most naturally associated with a deeply embedded active galactic nucleus (AGN). SED modelling yields log10(Lbol [erg/s]) ~ 43.7-44.0, implying black hole masses of log10(MBH [Msun]) ~ 5.7-6.7 under the assumption of Eddington-limited accretion. Given the very low stellar masses of the hosts, this corresponds to black-hole-to-stellar mass ratios of about 6-60%, well above the extrapolation of local scaling relations. The lack of X-ray detections suggests that the accretion may be either heavily obscured or intrinsically X-ray weak. Their SEDs also resemble those of Blue Excess Hot Dust Obscured Galaxies and show the characteristic V-shaped continuum seen in Little Red Dots, although with the inflection occurring at redder wavelengths. △ Less

Submitted 18 March, 2026; originally announced March 2026.

Comments: 16 pages (main text), 9 figures (+2 in the appendix), 2 tables (+6 in the appendix)

Little Red Dots: One Photometric Tag Concealing Diverse Spectroscopic Flavors of Massive Star Formation and Black Hole Activity

Authors: Pablo G. Pérez-González, Guillermo Barro, Stefano Carniani, Francesco D'Eugenio, George H. Rieke, Roberta Tripodi, Andrew J. Bunker, Xihan Ji, Rui Marques-Chaves, Daniel Schaerer, Giacomo Venturi, Flor Arévalo-González, Santiago Arribas, Pierluigi Rinaldi, Bruno Rodríguez Del Pino, Joris Witstok, Rachana Bhatawdekar, Leindert A. Boogaard, Stephane Charlot, Jacopo Chevallard, Luca Costantin, Mirko Curti, Emma Curtis-Lake, Emanuele Daddi, Kelcey Davis , et al. (40 additional authors not shown)

Abstract: We compile JWST/NIRSpec prism and MIRI data for 249 Little Red Dots (LRDs) at 2.3<z<9.3, forming a representative spectroscopic subset of NIRCam-selected LRDs. We derive a median stacked spectrum covering rest-frame 0.09-1.2 $μ$m, with MIRI photometry extending the spectral energy distribution to 4 $μ$m. Four additional stacks for subsamples defined by optical-to-UV luminosity ratios show that LRD… ▽ More We compile JWST/NIRSpec prism and MIRI data for 249 Little Red Dots (LRDs) at 2.3<z<9.3, forming a representative spectroscopic subset of NIRCam-selected LRDs. We derive a median stacked spectrum covering rest-frame 0.09-1.2 $μ$m, with MIRI photometry extending the spectral energy distribution to 4 $μ$m. Four additional stacks for subsamples defined by optical-to-UV luminosity ratios show that LRDs form a heterogeneous population spanning diverse continuum slopes and line properties. Assuming LRDs host super-massive black holes (BHs) surrounded by dense gas clouds, and stars accompany this core, we infer masses of $M_{BH}\sim10^{6.0-6.5}$ M$_\odot$ and $M_\bigstar\sim10^{8.3}$ M$_\odot$, corresponding to BH-to-stellar mass ratios of 1-2%. The stacks show ubiquitous UV and optical FeII emission, indicating a direct view of the broad-line region and high (but sub-Eddington) accretion ($λ_{Edd}=0.6\pm0.2$). We find a significant stellar contribution in the far-UV, reaching $\sim80$% in the bluest systems. Possible Wolf-Rayet features (HeII$λ$4687, nitrogen lines) are identified, tracing a young (3-7 Myr) compact starburst event. We also detect strong Balmer breaks and atypical Balmer, Paschen, [OIII], and optical and near-infrared HeI line ratios, and an absorption at $\sim4550$ Angstrom (probably linked to FeII), all consistent with radiative-transfer effects in high-density gas with warm temperatures (4000-7000 K). We find a diversity of LRD flavors modulated by the luminosity ratio between between a short ($\lesssim20$ Myr) and intense phase of BH activity, the most extreme stage lasting $\sim3-7$ Myr, characterized by near-Eddington-limit radiation, and a nuclear and compact starburst dominated by massive stars (even super-massive, $\mathrm{M}_\mathrm{SMS}\sim10^{5}$ M$_\odot$), all embedded in dense gas with modest dust content producing a variety of optical depths. △ Less

Submitted 27 February, 2026; v1 submitted 23 February, 2026; originally announced February 2026.

Comments: Submitted to ApJ. Comments welcome. Stacks available through https://doi.org/10.5281/zenodo.18733578

The Little Blue and Red Dots Rosetta Stones: Non-Gaussian broad lines, hot dust, and X-ray weakness

Authors: M. Brazzini, F. D'Eugenio, R. Maiolino, J. Lyu, C. DeCoursey, H. Übler, X. Ji, I. Juodžbalis, J. Scholtz, G. C. Jones, K. Hainline, E. Dalla Bontà, P. G. P érez-González, S. Geris, A. Harshan, C. Feruglio, M. Bischetti, G. Mazzolari, G. Rieke, S. Alberts, B. Trefoloni, S. Carniani, E. Parlanti, A. Marconi, G. Risaliti , et al. (9 additional authors not shown)

Abstract: The population of Active Galactic Nuclei (AGN) newly discovered by the James Webb Space Telescope (JWST) exhibits peculiar properties that distinguish it from both local type I AGN and high-redshift quasars. Most of these sources are compact, appearing as 'little dots': among them, the sub-class (10-30% of the total) characterized by significantly red optical colors has been named 'Little Red Dots… ▽ More The population of Active Galactic Nuclei (AGN) newly discovered by the James Webb Space Telescope (JWST) exhibits peculiar properties that distinguish it from both local type I AGN and high-redshift quasars. Most of these sources are compact, appearing as 'little dots': among them, the sub-class (10-30% of the total) characterized by significantly red optical colors has been named 'Little Red Dots' (LRDs), while here we analogously introduce the term 'Little Blue Dots' (LBDs) for the remaining, bluer sources (70-90%). We then present a comparative analysis of the prototypical representatives ('Rosetta Stones') of the two classes: GN-28074 at z=2.26, the Red Rosetta Stone, and GS-3073 at z=5.55, the Blue Rosetta Stone. In both Rosetta Stones the broad Balmer lines are better described by exponential profiles rather than single Gaussians, similarly to normal low-redshift type I AGN, indicating that exponential profiles are not unique to LRDs. They are both extremely X-ray weak, show strong auroral [OIII] 4363 emission, weak hot dust mid-IR emission, and no time variability. However, they differ in terms of excitation diagnostics: the HeII 4686 line is undetected in the Red Rosetta but strongly detected in the Blue Rosetta in both narrow and broad components, with the latter much broader than hydrogen Balmer lines. This supports BLR stratification and disfavors the cocoon electron-scattering scenario. An additional difference is the presence of prominent Balmer absorption in the Red Rosetta -- indicative of extremely dense gas along the line of sight -- but absent in the Blue Rosetta. Taken together, these results suggest that LRDs and LBDs share the same central engine as standard type I AGN, while differing in the amount and geometry of dense gas surrounding the accretion disk, and/or in their accretion properties. △ Less

Submitted 29 January, 2026; originally announced January 2026.

Comments: 22 pages, 13 figures. Submitted to A&A, comments are welcome

Clumps in High-Redshift Galaxies: Mass Scaling and Radial Trends from JADES

Authors: Yongda Zhu, Marcia J. Rieke, Zhiyuan Ji, Andrew J. Bunker, Courtney Carreira, A. Lola Danhaive, Qiao Duan, Eiichi Egami, Daniel J. Eisenstein, Kevin Hainline, Benjamin D. Johnson, Zheng Ma, Dávid Puskás, George H. Rieke, Pierluigi Rinaldi, Brant Robertson, Sandro Tacchella, Hannah Übler, Natalia C. Villanueva, Christina C. Williams, Christopher N. A. Willmer, Zihao Wu, Junyu Zhang

Abstract: Massive star-forming clumps are a prominent feature of high-redshift galaxies and are thought to trace gravitational fragmentation, feedback, and bulge growth in gas-rich disks. We present a statistical analysis of clumps in $\sim$3600 galaxies spanning $2 \lesssim z \lesssim 8$ from deep JWST/NIRCam imaging in the JADES GOODS--South field. Clumps are identified as residual features after subtract… ▽ More Massive star-forming clumps are a prominent feature of high-redshift galaxies and are thought to trace gravitational fragmentation, feedback, and bulge growth in gas-rich disks. We present a statistical analysis of clumps in $\sim$3600 galaxies spanning $2 \lesssim z \lesssim 8$ from deep JWST/NIRCam imaging in the JADES GOODS--South field. Clumps are identified as residual features after subtracting smooth Sérsic profiles, enabling a uniform, rest-frame optical census of sub-galactic structure. We characterize their physical properties, size--mass relations, and spatial distributions to constrain models of sub-galactic structure formation and evolution. We find that clumps in our sample are typically low-mass ($10^{\sim7-8}M_\odot$), actively star-forming, and show diverse gas-phase metallicity, dust attenuation, and stellar population properties. Their sizes and average pairwise separations increase with cosmic time (toward lower redshift), consistent with inside-out disk growth. The clump mass function follows a power law with slope $α= -1.50_{-0.17}^{+0.19}$, consistent with fragmentation in turbulent disks. We find a deficit of relatively young clumps near galaxy centers and a radial transition in the size--mass relation: outer clumps exhibit steeper, near-virial slopes ($R_{\rm e}\propto M_*^{\sim 0.3}$), while inner clumps follow flatter trends ($R_{\rm e}\propto M_*^{\sim 0.2}$), consistent with structural evolution via migration or disruption. These results provide new constraints on the formation, survival, and dynamical evolution of clumps, highlighting their role in shaping galaxy morphology during the peak of cosmic star formation. △ Less

Submitted 24 March, 2026; v1 submitted 22 January, 2026; originally announced January 2026.

Comments: Accepted for publication in ApJ. Figures 5, 7, and 9 show our key results

Undermassive Hosts of $z = 4-6 $ AGN from JWST/NIRCam Image Decomposition with CONGRESS, FRESCO, and JADES

Authors: Zheng Ma, Eichi Egami, Yongda Zhu, Fengwu Sun, Jianwei Lyu, Junyu Zhang, Christopher N. A. Willmer, Andrew J. Bunker, Stefano Carniani, Emma Curtis-Lake, Ryan Hausen, Xihan Ji, Zhiyuan Ji, Ignas Juodžbalis, Roberto Maiolino, George H. Rieke, Pierluigi Rinaldi, Yang Sun, Sandro Tacchella, Hannah Übler, Christina C. Williams

Abstract: In the local Universe, supermassive black hole (SMBH) masses strongly correlate with their host-galaxies' stellar masses ($M_{*}$), but galaxies hosting faint AGN recently found by JWST may deviate from this relation. To constrain the M$_{\text{BH}}$-M$_{*}$ relation at high redshift, we performed AGN-host image decomposition for 17 low-luminosity AGN galaxies at $z$ $\sim$ 4-6 using NIRCam images… ▽ More In the local Universe, supermassive black hole (SMBH) masses strongly correlate with their host-galaxies' stellar masses ($M_{*}$), but galaxies hosting faint AGN recently found by JWST may deviate from this relation. To constrain the M$_{\text{BH}}$-M$_{*}$ relation at high redshift, we performed AGN-host image decomposition for 17 low-luminosity AGN galaxies at $z$ $\sim$ 4-6 using NIRCam images in the JADES GOODS-N field. These sources are identified as AGNs from broad H$α$ emission lines detected by the CONGRESS and FRESCO surveys. We used galfit+MCMC to fit spatial profiles in 7 wide-band images and detected extended emission in 9 sources out of 17. The close spatial alignment between the extended components and the AGN centers indicates that this emission likely originates from the host galaxies. These sources are extended at 0.9-2.0~$μ$m, suggesting significant host-galaxy light in the rest-frame UV. For the sources with the host detection, the stellar mass inferred based on image decomposition result can be 1-2 dex lower than the results without image decomposition. The BH-to-stellar mass ratio spans $M_{\text{BH}}/M_\ast$ $\sim$ 0.01-1.48, placing them well above the local $M_{\text{BH}}$-$M_\ast$ relation. In contrast, the host-galaxy size-mass relation broadly agrees with previous measurements. Our results suggest that the host galaxies of these faint AGN are either genuinely under-massive compared to their black hole masses, or too compact to be spatially resolved. △ Less

Submitted 24 July, 2026; v1 submitted 22 January, 2026; originally announced January 2026.

Comments: Submitted to ApJ

JWST Advanced Deep Extragalactic Survey (JADES) Data Release 5: MIRI Coordinated Parallels in GOODS-S and GOODS-N

Authors: Stacey Alberts, Daniel J. Eisenstein, Andrew J. Bunker, Emma Curtis-Lake, Qiao Duan, Kevin Hainline, Ryan Hausen, Jakob M. Helton, Zhiyuan Ji, Benjamin D. Johnson, Jianwei Lyu, Jane Morrison, Pablo G. Perez-Gonzalez, George H. Rieke, Marcia Rieke, Pierluigi Rinaldi, Brant Robertson, Yang Sun, Sandro Tacchella, Christina C. Williams, Christopher N. A. Willmer, Zihao Wu

Abstract: Medium to ultra-deep mid-infrared imaging surveys with the James Webb Space Telescope (JWST)'s Mid-Infrared Instrument (MIRI) are reframing our view of the early Universe, from the emergence of ultra-red dusty and quiescent galaxies to the epoch of reionization to the first galaxies. Here we present the MIRI coordinated parallels component of the JADES program, which obtained ultra-deep (155 ks) i… ▽ More Medium to ultra-deep mid-infrared imaging surveys with the James Webb Space Telescope (JWST)'s Mid-Infrared Instrument (MIRI) are reframing our view of the early Universe, from the emergence of ultra-red dusty and quiescent galaxies to the epoch of reionization to the first galaxies. Here we present the MIRI coordinated parallels component of the JADES program, which obtained ultra-deep (155 ks) imaging at $7.7 μ$m over $\sim10$ arcmin$^2$ as well as medium depth ($\sim5-15$ ks) imaging at $7.7, 12.8$, and $15 μ$m over $\sim36$, 25, and 22 arcmin$^2$, respectively, in the GOODS-S and GOODS-N fields. This paper describes the data reduction, which combines the official JWST Calibration Pipeline with custom steps to optimize flagging of warm/hot pixels and optimize background subtraction. We further introduce a new step to address artifacts caused by persistence from saturating sources. The final, fully reduced JADES/MIRI mosaics are being released as part of JADES Data Release 5, along with prior-based forced photometry using NIRCam detection images, providing critical rest-frame near-infrared and optical constraints on early galaxy populations. △ Less

Submitted 22 January, 2026; originally announced January 2026.

Comments: 15 pages plus appendix

Ionizing Photon Production Efficiencies and Chemical Abundances at Cosmic Dawn Revealed by Ultra-Deep Rest-Frame Optical Spectroscopy of JADES-GS-z14-0

Authors: Jakob M. Helton, Jane E. Morrison, Kevin N. Hainline, Francesco D'Eugenio, George H. Rieke, Stacey Alberts, Stefano Carniani, Joel Leja, Yijia Li, Pierluigi Rinaldi, Jan Scholtz, Meredith Stone, Christopher N. A. Willmer, Zihao Wu, William M. Baker, Andrew J. Bunker, Stephane Charlot, Jacopo Chevallard, Nikko J. Cleri, Mirko Curti, Emma Curtis-Lake, Eiichi Egami, Daniel J. Eisenstein, Peter Jakobsen, Zhiyuan Ji , et al. (18 additional authors not shown)

Abstract: JWST has discovered an early period of galaxy formation that was more vigorous than expected, which has challenged our understanding of the early Universe. In this work, we present the longest spectroscopic integration ever acquired by JWST/MIRI. This spectrum covers the brightest rest-frame optical nebular emission lines for the luminous galaxy JADES-GS-z14-0 at $z > 14$. Most notably, we detect… ▽ More JWST has discovered an early period of galaxy formation that was more vigorous than expected, which has challenged our understanding of the early Universe. In this work, we present the longest spectroscopic integration ever acquired by JWST/MIRI. This spectrum covers the brightest rest-frame optical nebular emission lines for the luminous galaxy JADES-GS-z14-0 at $z > 14$. Most notably, we detect $[\mathrm{OIII}] λλ4959,5007$ at $\approx 11 σ$ and $\mathrm{H}α$ at $\approx 4 σ$ with these ultra-deep observations. These lines reveal that JADES-GS-z14-0 has low dust attenuation with a recent star-formation rate of $\mathrm{SFR} \approx 10 \pm 2\ M_{\odot} / \mathrm{yr}$, star-formation rate surface density of $Σ_{\mathrm{SFR}} \approx 23 \pm 5\ M_{\odot}/\mathrm{yr}/\mathrm{kpc}^{2}$, and ionizing photon production efficiency of $ξ_{\mathrm{ion}} \approx 10^{25.3 \pm 0.1}\ \mathrm{Hz/erg}$. Using standard strong-line diagnostics, we infer a gas-phase oxygen abundance of $[\mathrm{O/H}] \approx -1.1 \pm 0.4$ ($\approx 10\%\ Z_{\odot}$), carbon-to-oxygen ratio of $[\mathrm{C/O}] \approx -0.4 \pm 0.4$, ionization parameter of $\mathrm{log}_{10}(U) \gtrsim -2.4$, and density of $n_{\mathrm{H}} \approx 720 \pm 210\ \mathrm{cm}^{-3}$. Using detailed photoionization modeling, we instead derive $[\mathrm{O/H}] \approx -0.3_{-0.4}^{+0.4}$ ($\approx 50\%\ Z_{\odot}$) and $\mathrm{log}_{10}(U) \approx -1.5_{-0.4}^{+0.3}$. The inferred properties of JADES-GS-z14-0 are similar to those measured for similarly luminous galaxies at $z > 10$ with previous MIRI/Spectroscopy, such as GHZ2/GLASSz12, GN-z11, and MACS0647-JD1. Existing simulations are unable to reproduce the empirical and inferred properties of JADES-GS-z14-0. This work demonstrates an important step toward understanding the formation of the first stars and heavy elements in the Universe. [Abridged] △ Less

Submitted 22 December, 2025; originally announced December 2025.

Comments: Submitted to ApJL; main text has 23 pages, 8 figures, and 2 tables; comments are welcome!

JWST observes the assembly of a massive galaxy at z~4

Authors: Aayush Saxena, Roderik A. Overzier, Catarina Aydar, Jianwei Lyu, George H. Rieke, Victoria Reynaldi, Montserrat Villar-Martín, Krisztina Éva Gabányi, Kenneth J. Duncan, Sándor Frey, Andrew Humphrey, George Miley, Laura Pentericci, Krisztina Perger, Huub Röttgering, Philip Best, Sarah E. I. Bosman, Gyorgy Mező, Masafusa Onoue, Zsolt Paragi, Bram Venemans

Abstract: We present JWST observations of the radio galaxy TGSSJ1530+1049, spectroscopically confirmed at $z=4.0$. NIRCam images and NIRSpec/IFU spectroscopy (R=2700) show that TGSSJ1530+1049 is part of one of the densest-known structures of continuum and line-emitting objects found at these redshifts. NIRCam images show a number of distinct continuum objects and evidence of interactions traced by diffuse e… ▽ More We present JWST observations of the radio galaxy TGSSJ1530+1049, spectroscopically confirmed at $z=4.0$. NIRCam images and NIRSpec/IFU spectroscopy (R=2700) show that TGSSJ1530+1049 is part of one of the densest-known structures of continuum and line-emitting objects found at these redshifts. NIRCam images show a number of distinct continuum objects and evidence of interactions traced by diffuse emission, and the NIRSpec IFU cube reveals further strong line emitting regions. We identify six continuum and four additional strong H$α$ emitting sources with weaker or no underlying continuum within the 3x3 arcsec IFU field. From spatial alignment with high-resolution radio data and emission line profiles, the radio AGN host galaxy is clearly identified. The bright H$α$ emission (but not the optical components) is distributed remarkably linearly along the radio axis, suggestive of a biconical illumination zone by a central obscured AGN. The emission line kinematics indicate jet-gas interactions on scales of a few kpc. However, due to large relative velocities and presence of underlying continuum, the alignment with the radio structure appears to be, at least partly, caused by a particular configuration of interacting galaxies. At least four objects within a 10x10 (projected) kpc$^2$ area which includes the radio source have high stellar masses ($\log(M_\star/M_\odot)>10.3$) and star formation rates in the range $70-163\,M_\odot$ yr$^{-1}$. Using a stellar mass-based analysis, we predict a total dark matter halo mass of $\approx10^{13} M_\odot$. Based on the physical separations and velocity differences between the galaxies, it is expected that these galaxies will merge to form a massive galaxy within a few Gyr. The system qualitatively resembles the forming brightest cluster galaxies in cosmological simulations that form early through a rapid succession of mergers. △ Less

Submitted 23 March, 2026; v1 submitted 17 November, 2025; originally announced November 2025.

Comments: 15 pages, 9 figures; Published in the Open Journal of Astrophysics; Based on JWST programs GO 1964 and GTO 1205

The Relation Between AGN and Host Galaxy Properties in the JWST Era: II. The merger-driven evolution of Seyferts at Cosmic Noon

Authors: Nina Bonaventura, Jianwei Lyu, George H. Rieke, Andrew J. Bunker, Chris J. Willott, Christopher N. A. Willmer

Abstract: In Paper I, we exploited the unsurpassed resolution and depth of JWST/NIRCam imagery to investigate the relationship between AGN and host-galaxy properties in the JWST era, finding a correlation between the level of spatial disturbance (as measured by shape asymmetry, $A_S$) and obscuration ($N_H$). Here in Paper II, we report an expansion of our X-ray and infrared analysis of Seyfert-luminosity h… ▽ More In Paper I, we exploited the unsurpassed resolution and depth of JWST/NIRCam imagery to investigate the relationship between AGN and host-galaxy properties in the JWST era, finding a correlation between the level of spatial disturbance (as measured by shape asymmetry, $A_S$) and obscuration ($N_H$). Here in Paper II, we report an expansion of our X-ray and infrared analysis of Seyfert-luminosity host galaxies with four additional metrics to the single-metric morphology analysis of Paper I, as well as new samples of inactive control galaxies. This expanded study of one of the largest and most complete, multi-wavelength samples of AGN detected at $0.6<z<2.4$ in the GOODS-South and North fields, confirms that mergers surprisingly play a significant role in obscured, sub-quasar AGN host galaxies. Additionally, the pattern of morphological disturbances observed amongst the X-ray- and mid-IR-selected AGN suggests that these represent different phases of AGN evolution tied to a major-merger timeline, as opposed to distinct populations of AGN. These results indicate that mergers are important in triggering sub-quasar AGN at these redshifts. △ Less

Submitted 14 October, 2025; v1 submitted 13 October, 2025; originally announced October 2025.

Confirming Near- to Mid-IR Photometrically-Identified Obscured AGNs in the JWST era

Authors: George H. Rieke, Yang Sun, Jianwei Lyu, Christopher N. A. Willmer, Yongda Zhu, Pierluigi Rinaldi, Meredith A. Stone, Kevin N. Hainline, Pablo G. Perez-Gonzalez

Abstract: We evaluate the underlying assumptions for the identification of Active Galactic Nuclei (AGNs) through near- and mid-infrared photometry and spectral energy distribution (SED) fitting out to z ~ 3. For massive galaxies, log(M) > 9.5, our high resolution spectra of the rest optical range generally confirm the results of SED fitting, which relies primarily on excesses above the stellar emission betw… ▽ More We evaluate the underlying assumptions for the identification of Active Galactic Nuclei (AGNs) through near- and mid-infrared photometry and spectral energy distribution (SED) fitting out to z ~ 3. For massive galaxies, log(M) > 9.5, our high resolution spectra of the rest optical range generally confirm the results of SED fitting, which relies primarily on excesses above the stellar emission between 1 and 6 microns to identify AGN. However, the method is undermined if the redshift used for the SED fitting is incorrect. Low mass galaxies, log(M) < 9:5, can contain relatively warm dust that emits in the 4 - 6 micron range. We show that the potential contamination of AGN samples by purely star forming low-mass galaxies can be avoided by the use of the infrared properties of Haro 11 as a limiting star-forming SED template. However, relatively few star forming galaxies emit as strongly in the 3 - 6 micron range as this template, so this could result in missing some obscured AGNs to avoid a minor contamination. Including the behavior of the galaxies at rest lamda ~ 13.5 microns can mitigate this problem and yield more complete samples of bona fide AGN. JWST/MIRI supports this approach out to z ~ 0.6. △ Less

Submitted 8 October, 2025; originally announced October 2025.

Comments: ApJ, in press

JWST/MIRI Imaging of the Warm Dust Component of the Epsilon Eridani Debris Disk

Authors: Schuyler G. Wolff, András Gáspár, George Rieke, Jarron M. Leisenring, Antranik A. Sefilian, Marie Ygouf, Jorge Llop-Sayson

Abstract: We present JWST/MIRI observations of the debris disk surrounding the nearby, solar analog Epsilon Eridani obtained as part of the Archetypal Debris Disk GTO program. Multi-wavelength images from 15, 18, 21, and 25.5 $μm$ show a smooth dust distribution with no evidence of sculpting by massive planets outside of 5 au. Maps of the color temperature and opacity constrain the dust properties while rad… ▽ More We present JWST/MIRI observations of the debris disk surrounding the nearby, solar analog Epsilon Eridani obtained as part of the Archetypal Debris Disk GTO program. Multi-wavelength images from 15, 18, 21, and 25.5 $μm$ show a smooth dust distribution with no evidence of sculpting by massive planets outside of 5 au. Maps of the color temperature and opacity constrain the dust properties while radiative transfer modeling of a warm dust component traces the interaction between the debris disk and Epsilon Eri b ($\sim$3.5 au). Dynamical and collisional modeling further shows that the disk morphology is dominated by dust produced in the outer planetesimal belt ($\sim 70 \, au$) moving inward via stellar wind drag. We confirm the presence of a disk interior to the Epsilon Eri b orbit first detected from mid-IR interferometry. Drag dominated inner disk regions have also been observed around Vega and Fomalhaut hinting at the diversity of asteroid belt analogs. △ Less

Submitted 27 October, 2025; v1 submitted 29 September, 2025; originally announced September 2025.

Journal ref: 2025 AJ 170 244

Quasar Radiative Feedback May Suppress Galaxy Growth on Intergalactic Scales at $z = 6.3$

Authors: Yongda Zhu, Eiichi Egami, Xiaohui Fan, Fengwu Sun, George D. Becker, Christopher Cain, Huanqing Chen, Anna-Christina Eilers, Yoshinobu Fudamoto, Jakob M. Helton, Xiangyu Jin, Maria Pudoka, Andrew J. Bunker, Zheng Cai, Jaclyn B. Champagne, Zhiyuan Ji, Xiaojing Lin, Weizhe Liu, Hai-Xia Ma, Zheng Ma, Roberto Maiolino, George H. Rieke, Marcia J. Rieke, Pierluigi Rinaldi, Yang Sun , et al. (5 additional authors not shown)

Abstract: We present observational evidence that intense ionizing radiation from a luminous quasar suppresses nebular emission in nearby galaxies on intergalactic scales at $z=6.3$. Using JWST/NIRCam grism spectroscopy from the SAPPHIRES and EIGER programs, we identify a moderate but statistically significant decline in [O\,\textsc{iii}]\,$\lambda5008$ luminosity relative to the UV continuum (… ▽ More We present observational evidence that intense ionizing radiation from a luminous quasar suppresses nebular emission in nearby galaxies on intergalactic scales at $z=6.3$. Using JWST/NIRCam grism spectroscopy from the SAPPHIRES and EIGER programs, we identify a moderate but statistically significant decline in [O\,\textsc{iii}]\,$\lambda5008$ luminosity relative to the UV continuum ($L_{5008}/L_{1500}$) among galaxies within $\sim$ 7 comoving Mpc (cMpc) of the quasar J0100$+$2802, the most UV-luminous quasar known at this epoch ($M_{1450}=-29.26$). While $L_{1500}$ remains roughly constant with transverse distance, $L_{5008}$ increases significantly, suggesting suppression of very recent star formation toward the quasar. The effect persists after controlling for completeness, local density, and UV luminosity, and correlates with the projected photoionization-rate profile $Γ_{\mathrm{qso}}$. A weaker but directionally consistent suppression in $L_{5008}/L_{1500}$ is also observed along the line of sight. The transverse suppression radius ($\sim$ 7 cMpc) implies a recent radiative episode with a cumulative duration $\sim$ 3.1 Myr, shorter than required for thermal photoheating to dominate and thus more naturally explained by rapid H$_2$ photodissociation and related radiative processes. Environmental effects alone appear insufficient to explain the signal. Our results provide direct, geometry-based constraints on large-scale quasar radiative feedback and recent quasar lifetimes. △ Less

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

Comments: Accepted for publication in The Astrophysical Journal Letters (ApJL); to be presented at AAS 247

SMILES Data Release II: Probing Galaxy Evolution during Cosmic Noon and Beyond with NIRSpec Medium-Resolution Spectra

Authors: Yongda Zhu, Nina Bonaventura, Yang Sun, George H. Rieke, Stacey Alberts, Jianwei Lyu, Irene Shivaei, Jane E. Morrison, Zhiyuan Ji, Eiichi Egami, Jakob M. Helton, Marcia J. Rieke, Pierluigi Rinaldi, Fengwu Sun, Christopher N. A. Willmer

Abstract: We present the second data release of the Systematic Mid-Infrared Instrument (MIRI) Legacy Extragalactic Survey (SMILES), focusing on JWST/NIRSpec medium-resolution spectroscopy of galaxies across cosmic time. This release includes spectroscopic observations of 166 galaxies spanning $0 < z < 7.5$, sampling star-forming galaxies, quiescent systems, and active galactic nuclei (AGN), with an emphasis… ▽ More We present the second data release of the Systematic Mid-Infrared Instrument (MIRI) Legacy Extragalactic Survey (SMILES), focusing on JWST/NIRSpec medium-resolution spectroscopy of galaxies across cosmic time. This release includes spectroscopic observations of 166 galaxies spanning $0 < z < 7.5$, sampling star-forming galaxies, quiescent systems, and active galactic nuclei (AGN), with an emphasis on galaxies at cosmic noon ($z \sim 1$-3). We describe the target selection strategy, the observational setup with the G140M/F100LP and G235M/F170LP gratings, and the data calibration process. The final data products include the reduced spectra, redshift catalog, emission-line catalogs produced with \texttt{GELATO} for emission-line galaxies and \texttt{pPXF} fits for quiescent systems, and ancillary spectral energy distribution (SED) fit results derived from multi-band photometry. The SMILES NIRSpec dataset enables investigations of obscured AGN, multi-phase outflows, ionizing properties, and the role of environment in galaxy evolution. △ Less

Submitted 9 December, 2025; v1 submitted 17 August, 2025; originally announced August 2025.

Comments: Accepted for publication in ApJ. The data products can be found at https://github.com/ydzhuastro/smiles_dr2 before publishing on STScI/MAST; DR1 (MIRI) can be found at https://github.com/staceyalberts/JWST-SMILES and http://dx.doi.org/10.17909/et3f-zd57

A Promise for the JWST era: Massive black holes directly collapsed from wave dark matter haloes, and Star formation in and around their accretion flows

Authors: Xiaobo Dong, Yongda Zhu, Marcia Rieke, George Rieke, Xinyu Li, Peter Behroozi, Haixia Ma, Runyu Meng, Zhiying Mao, Zhe Sun

Abstract: There are several puzzling phenomena from recent JWST observations, which seem to push the standard ΛCDM cosmology over the edge. All those puzzles can be understood in a coherent way if we assume that first massive black holes (MBHs, the "heavy eggs") formed by directly collapsing from wave CDM haloes, which can be even earlier than the formation of first galaxies (the "chickens"). We elucidate t… ▽ More There are several puzzling phenomena from recent JWST observations, which seem to push the standard ΛCDM cosmology over the edge. All those puzzles can be understood in a coherent way if we assume that first massive black holes (MBHs, the "heavy eggs") formed by directly collapsing from wave CDM haloes, which can be even earlier than the formation of first galaxies (the "chickens"). We elucidate two false obstacles that have been believed to prevent wave CDM haloes from collapsing into black holes (namely "maximum stable mass" and "bosenova") and point out that general-relativistic instabilities (e.g., the non-axisymmetric instability numerically found in spinning scalar-field boson stars) could serve as the concrete mechanisms for direct-collapse black holes (DCBHs) born from wave dark matter. Once the MBHs formed, star formation bursts in and around the accretion flows, characteristic of a special mode in compact regions of high gravitational accelerations. △ Less

Submitted 12 August, 2025; originally announced August 2025.

Comments: Comments welcome. "In the beginning, let's think in concepts."

Searching for Planets Orbiting $ε$~Eridani with JWST/NIRCam

Authors: Jorge Llop-Sayson, Charles Beichman, Geoffrey Bryden, Marie Ygouf, Andras Gaspar, William Thompson, Aniket Sanghi, Dimitri Mawet, Alexandra Z. Greenbaum, Jarron Leisenring, Schuyler Wolff, Marcia Rieke, George Rieke

Abstract: We present observations of \epseri~with the JWST/NIRCam coronagraph aimed at imaging planets orbiting within this system. In particular, these observations targeted (1) the Jupiter-like planet, first detected orbiting at 3.5 AU with radial velocity observations, and (2) the planet postulated to be responsible for carving the edges of \epseri's outer ring, expected to orbit at 40-50 AU. However, no… ▽ More We present observations of \epseri~with the JWST/NIRCam coronagraph aimed at imaging planets orbiting within this system. In particular, these observations targeted (1) the Jupiter-like planet, first detected orbiting at 3.5 AU with radial velocity observations, and (2) the planet postulated to be responsible for carving the edges of \epseri's outer ring, expected to orbit at 40-50 AU. However, no point sources were detected at a statistically significant level. We report new, improved upper limits at 4 $μ$m: $\sim$1e-7~contrast at 1\arcsec, and $\sim$2e-8~beyond 5\arcsec. The latter contrast limit precludes Saturn-mass planets at separations $>$16~AU given current models. We also report upper limits for \epseri's disk emission at 4 $μ$m. While the radial surface brightness profile shows no evidence of emission, we detect a 1-$σ$ surface brightness signal on the east side of the system, consistent with forward scattering emission expected for \epseri's disk inclination. Finally, we evaluate the performance of the 3-roll observation strategy, which was first employed in these observations: the gains in contrast are modest, with 20-30\% improvements with respect to the conventional 2-roll strategy. △ Less

Submitted 11 August, 2025; originally announced August 2025.

Comments: Accepted for publication in AJ

JADES-GS-z14-1: A Compact, Faint Galaxy at $z\approx14$ with Weak Metal Lines from Extremely Deep JWST MIRI, NIRCam, and NIRSpec Observations

Authors: Zihao Wu, Daniel J. Eisenstein, Benjamin D. Johnson, Peter Jakobsen, Stacey Alberts, Santiago Arribas, William M. Baker, Andrew J. Bunker, Stefano Carniani, Stéphane Charlot, Jacopo Chevallard, Mirko Curti, Emma Curtis-Lake, Francesco D'Eugenio, Kevin Hainline, Jakob M. Helton, Tiger Yu-Yang Hsiao, Xihan Ji, Zhiyuan Ji, Tobias J. Looser, George Rieke, Pierluigi Rinaldi, Brant Robertson, Jan Scholtz, Fengwu Sun , et al. (7 additional authors not shown)

Abstract: JWST has shed light on galaxy formation and metal enrichment within 300 Myr of the Big Bang. While luminous galaxies at $z > 10$ often show significant [O III]$λλ$4959, 5007 emission lines, it remains unclear whether such features are prevalent among fainter, more typical galaxies due to observational limits. We present deep imaging and spectroscopy of JADES-GS-z14-1 at… ▽ More JWST has shed light on galaxy formation and metal enrichment within 300 Myr of the Big Bang. While luminous galaxies at $z > 10$ often show significant [O III]$λλ$4959, 5007 emission lines, it remains unclear whether such features are prevalent among fainter, more typical galaxies due to observational limits. We present deep imaging and spectroscopy of JADES-GS-z14-1 at $z_\mathrm{spec}=13.86^{+0.04}_{-0.05}$, currently the faintest spectroscopically confirmed galaxy at $z\approx 14$. It serendipitously received 70.7 hours of MIRI/F770W imaging in the JWST Advanced Deep Extragalactic Survey (JADES), the deepest MIRI exposure for any high-redshift galaxy to date. Nonetheless, we detect only tentative F770W emission of $7.9\pm2.8$ nJy at $2.8σ$ significance, constraining the total equivalent width of [O III]$λλ$4959, 5007 + H$β$ to $520^{+400}_{-380}$ A, weaker than most $z > 10$ galaxies with MIRI detections. This source is unresolved across 16 NIRCam bands, implying a physical radius $\lesssim50$ pc. NIRSpec/PRISM spectroscopy totaling 56 hours reveals no rest-frame ultraviolet emission lines above $3 σ$. Stellar population synthesis suggests a stellar mass $\sim4\times 10^{7}$ $\mathrm{M_\odot}$ and a star formation rate $\sim 2$ $\mathrm{M_\odot yr^{-1}}$. The absence of strong metal emission lines despite intense star formation suggests a gas-phase metallicity below 10% solar and potentially a high escape fraction of ionizing photons. These deep observations provide rare constraints on faint, early galaxies, tracing the onset of chemical enrichment and ionization in the early Universe. △ Less

Submitted 1 September, 2025; v1 submitted 30 July, 2025; originally announced July 2025.

Comments: Accepted for publication in ApJ

Beyond the Dot: an LRD-like nucleus at the Heart of an IR-Bright Galaxy and its implications for high-redshift LRDs

Authors: Pierluigi Rinaldi, George H. Rieke, Zihao Wu, Carys J. E. Gilbert, Fabio Pacucci, Luigi Barchiesi, Stacey Alberts, Stefano Carniani, Andrew J. Bunker, Rachana Bhatawdekar, Francesco D'Eugenio, Zhiyuan Ji, Benjamin D. Johnson, Kevin Hainline, Vasily Kokorev, Nimisha Kumari, Edoardo Iani, Jianwei Lyu, Roberto Maiolino, Eleonora Parlanti, Brant E. Robertson, Yang Sun, Cristian Vignali, Christina C. Williams, Christopher N. A. Willmer , et al. (1 additional authors not shown)

Abstract: Little Red Dots (LRDs) are compact, red sources discovered by JWST at high redshift ($z \gtrsim 4$), marked by distinctive 'V-shaped' spectral energy distributions (SEDs) and often interpreted as rapidly accreting Active Galactic Nuclei (AGNs). Their true nature remains unclear, however, and their evolutionary connection to their lower-redshift counterparts is still poorly constrained. Thus, we pr… ▽ More Little Red Dots (LRDs) are compact, red sources discovered by JWST at high redshift ($z \gtrsim 4$), marked by distinctive 'V-shaped' spectral energy distributions (SEDs) and often interpreted as rapidly accreting Active Galactic Nuclei (AGNs). Their true nature remains unclear, however, and their evolutionary connection to their lower-redshift counterparts is still poorly constrained. Thus, we present WISEA J123635.56+621424.2, here dubbed {\it the Saguaro}, a $z=2.0145$ galaxy in GOODS-North, as a possible analog of high-redshift LRDs and a potential missing link in their evolutionary path toward lower-redshift systems. It features a compact LRD-like nucleus surrounded by a face-on spiral host. Its connection to LRDs includes that: (1) its nuclear spectrum shows a clear `V-shaped'' SED; and (2) when redshifted to $z=7$, surface-brightness dimming makes the host undetectable, thus mimicking an LRD. This suggests that high-redshift LRDs may be embedded in extended hosts. To test this, we stack rest-frame UV images of 99 photometrically selected LRDs, revealing faint, diffuse emission. Stacking in redshift bins reveals mild radial growth, consistent with the expected galaxy size evolution. A simple analytic model confirms that surface-brightness dimming alone can explain their compact appearance. Lastly, we show that {\it the Saguaro} is not unique by describing similar objects from the literature at $z\lesssim3.5$. Taken together, our results support a scenario in which LRDs may not be a distinct population, but could instead be the visible nuclei of galaxies undergoing a short-lived, perhaps AGN-dominated, evolutionary phase, with their compact, red appearance driven largely by observational biases. △ Less

Submitted 16 June, 2026; v1 submitted 23 July, 2025; originally announced July 2025.

Comments: 33 pages, 13 plots, and 3 tables. Accepted for publication in ApJ

The $z=7.08$ quasar ULAS J1120+0641 May Never Reach a "Normal" Black Hole to Stellar Mass Ratio

Authors: Meredith A. Stone, George H. Rieke, Jianwei Lyu, Michael K. Florian, Kevin N. Hainline, Yang Sun, Yongda Zhu

Abstract: JWST observations of quasars in the Epoch of Reionization have revealed that many lie in host galaxies that are severely undermassive relative to the supermassive black holes. It is unclear how these systems will evolve to the tight local relation between stellar mass and black hole mass. We search for companions around the z=7.08 quasar ULAS J1120+0641 using JWST/NIRCam narrow, medium, and wide-b… ▽ More JWST observations of quasars in the Epoch of Reionization have revealed that many lie in host galaxies that are severely undermassive relative to the supermassive black holes. It is unclear how these systems will evolve to the tight local relation between stellar mass and black hole mass. We search for companions around the z=7.08 quasar ULAS J1120+0641 using JWST/NIRCam narrow, medium, and wide-band photometry to identify [O III] emitters at the quasar redshift, and explore the potential for growth of the host galaxy through future mergers. We find 22 sources near the quasar's redshift across our two 4.4 arcmin$^2$ fields, indicating that environment of ULAS J1120+0641 is strongly overdense in z~7.1 galaxies relative to the field. We estimate the potential future mass budget of the quasar host galaxy by summing the current stellar and gas masses of the quasar host and surrounding galaxies, correcting for incompleteness and selection effects. With no further black hole growth, ULAS J1120+0641 is unlikely to reach a $M_{\mathrm{BH}}/M_*$ ratio less than ~2.5% at z=0, still much higher than typical for local galaxies. However, such systems -- a quiescent black hole in a low-luminosity galaxy -- may have escaped detection locally if they are sufficiently distant. △ Less

Submitted 15 August, 2025; v1 submitted 17 July, 2025; originally announced July 2025.

Comments: 23 pages, 8 figures plus 4 in appendix. Replacing with revised version after submitting to ApJ, comments welcome

Discovery of Volatile Gas in the Giant Impact Disk around the 150-Myr old HD 23514

Authors: Kate Y. L. Su, Attila Moór, Chengyan Xie, Ilaria Pascucci, George H. Rieke, Ágnes Kóspál, Mark C. Wyatt, Péter Ábrahám, Luca Matrà, Zoe Roumeliotis, D. J. Wilner

Abstract: We report the discovery of CO$_2$ gas emission around HD 23514, an F5V star in the $\sim$150 Myr-old Pleiades cluster, hosting one of the rare giant-impact disks with unique mineralogy dominated by silica dust. We show that the dust feature remains stable over several decades, and that the sub-$μ$m grains, which give rise to the $\sim$9 $μ$m feature, are co-spatial with the hot CO$_2$ molecules wi… ▽ More We report the discovery of CO$_2$ gas emission around HD 23514, an F5V star in the $\sim$150 Myr-old Pleiades cluster, hosting one of the rare giant-impact disks with unique mineralogy dominated by silica dust. We show that the dust feature remains stable over several decades, and that the sub-$μ$m grains, which give rise to the $\sim$9 $μ$m feature, are co-spatial with the hot CO$_2$ molecules within the sub-au vicinity of the star. Examining the Spitzer spectrum taken 15 years earlier, we show that the CO$_2$ emission was also present at 4.3 $σ$ significance. The existence of tiny silica grains and volatile gas requires special conditions to prevent the rapid loss caused by stellar radiation pressure and photodissociation. We explore several pathways explaining the observed properties and suggest that a past giant impact and/or stripping atmospheric event, involving large bodies with volatile content similar to the carbonaceous chondritic material, can simultaneously explain both the silica and volatile emission. Our discovery provides an important context for the amount of volatiles that a newly formed planet or the largest planetesimals could retain during the giant impact phase in the early solar system evolution. △ Less

Submitted 6 July, 2025; v1 submitted 25 June, 2025; originally announced June 2025.

Comments: accepted for publication in ApJL; fixed typos; updated DOI

The Identification of Two JWST/NIRCam-Dark Starburst Galaxies at $z=6.6$ with ALMA

Authors: Fengwu Sun, Jinyi Yang, Feige Wang, Daniel J. Eisenstein, Roberto Decarli, Xiaohui Fan, George H. Rieke, Eduardo Bañados, Sarah E. I. Bosman, Zheng Cai, Jaclyn B. Champagne, Luis Colina, Francesco D'Eugenio, Yoshinobu Fudamoto, Mingyu Li, Xiaojing Lin, Weizhe Liu, Jianwei Lyu, Chiara Mazzucchelli, Xiangyu Jin, Hyunsung D. Jun, Yunjing Wu, Huanian Zhang

Abstract: We analyze two dusty star-forming galaxies at $z=6.6$. These galaxies are selected from the ASPIRE survey, a JWST Cycle-1 medium and ALMA Cycle-9 large program targeting 25 quasars and their environments at $z\simeq6.5 - 6.8$. These galaxies are identified as companions to UV-luminous quasars and robustly detected in ALMA continuum and [C II] emission, yet they are extraordinarily faint at the NIR… ▽ More We analyze two dusty star-forming galaxies at $z=6.6$. These galaxies are selected from the ASPIRE survey, a JWST Cycle-1 medium and ALMA Cycle-9 large program targeting 25 quasars and their environments at $z\simeq6.5 - 6.8$. These galaxies are identified as companions to UV-luminous quasars and robustly detected in ALMA continuum and [C II] emission, yet they are extraordinarily faint at the NIRCam wavelengths (down to $>28.0$ AB mag in the F356W band). They are more obscured than galaxies like Arp220, and thus we refer to them as "NIRCam-dark" starburst galaxies (star formation rate $\simeq 80 - 250\,\mathrm{M}_{\odot}\,\mathrm{yr}^{-1}$). Such galaxies are typically missed by (sub)-millimeter blank-field surveys. From the star-formation history (SFH), we show that the NIRCam-dark galaxies are viable progenitors of massive quiescent galaxies at $z\gtrsim4$ and descendants of UV-luminous galaxies at $z>10$. Although it is hard to constrain their number density from a quasar survey, we conclude that NIRCam-dark galaxies can be as abundant as $n\sim10^{-5.5}$ Mpc$^{-3}$ assuming a light halo occupation model. If true, this would equal to $\sim$30% of the number densities of both the quiescent galaxies at $z\gtrsim4$ and UV-luminous galaxies at $z>10$. We further predict that analogs at $z\sim8$ should exist according to the SFH of early massive quiescent galaxies. However, they may fall below the current detection limits of wide JWST and ALMA surveys, thus remaining "JWST-dark". To fully trace the evolution of massive galaxies and dust-obscured cosmic star formation at $z\gtrsim8$, wide-field JWST/NIRCam imaging and slitless spectroscopic surveys of early protoclusters are essential. △ Less

Submitted 6 June, 2025; originally announced June 2025.

Comments: 14 pages, 5 figures, submitted to an AAS journal. Comments are welcome

The Stellar Populations and Rest-Frame Colors of Star-Forming Galaxies at $z \approx 8$: Exploring the Impact of Filter Choice and Star Formation History Assumption with JADES

Authors: Jakob M. Helton, Stacey Alberts, George H. Rieke, Kevin N. Hainline, Zhiyuan Ji, Marcia J. Rieke, Benjamin D. Johnson, Brant Robertson, Sandro Tacchella, Lily Whitler, William M. Baker, Rachana Bhatawdekar, Kristan Boyett, Andrew J. Bunker, Phillip A. Cargile, Stefano Carniani, Stephane Charlot, Jacopo Chevallard, Emma Curtis-Lake, Eiichi Egami, Daniel J. Eisenstein, Ryan Hausen, Jianwei Lyu, Roberto Maiolino, Erica Nelson , et al. (8 additional authors not shown)

Abstract: Our understanding of the physical properties of star-forming galaxies during the Epoch of Reionization (EoR, at $z > 6$) suffers from degeneracies among the apparent properties of the stars, the nebular gas, and the dust. These degeneracies are most prominent with photometry, which has insufficient (1) spectral resolution and (2) rest-frame spectral coverage. We explore ways to break these degener… ▽ More Our understanding of the physical properties of star-forming galaxies during the Epoch of Reionization (EoR, at $z > 6$) suffers from degeneracies among the apparent properties of the stars, the nebular gas, and the dust. These degeneracies are most prominent with photometry, which has insufficient (1) spectral resolution and (2) rest-frame spectral coverage. We explore ways to break these degeneracies with a sample of $N = 22$ high-redshift star-forming galaxies at $7 < z_{\mathrm{phot}} \leq 9$, using some of the deepest existing imaging from JWST/NIRCam and JWST/MIRI with JADES. Key to this study is the imaging from JWST/MIRI at $7.7\ μ\mathrm{m}$, which provides coverage of the rest-frame $I$-band at the observed redshifts. We infer stellar population properties and rest-frame colors using a variety of filter sets and star formation history assumptions to explore the impact of these choices. Evaluating these quantities both with and without the $7.7\ μ\mathrm{m}$ data point shows that dense spectral coverage with JWST/NIRCam (eight or more filters, including at least one medium-band) can compensate for lacking the rest-frame $I$-band coverage for the vast majority ($\approx 80\%$) of our sample. Furthermore, these galaxy properties are most consistently determined by assuming the delayed-tau star formation history, which provides the smallest offsets and scatters around these offsets when including JWST/MIRI. Within extragalactic surveys like JADES and CEERS, our findings suggest that robust characterization of the stellar population properties and rest-frame colors for high-redshift star-forming galaxies is possible with JWST/NIRCam alone at $z \approx 8$. △ Less

Submitted 2 June, 2025; originally announced June 2025.

Comments: Submitted to ApJ; main text has 22 pages, 8 figures (including 2 figure sets) and 4 tables; appendix has 2 pages, 2 figures (including 2 figure sets), and 5 tables

The First Photometric Evidence of a Transient/Variable Source at z>5 with JWST

Authors: Christa DeCoursey, Eiichi Egami, Fengwu Sun, Arshia Akhtarkavan, Rachana Bhatawdekar, Andrew J. Bunker, David A. Coulter, Michael Engesser, Ori D. Fox, Sebastian Gomez, Kohei Inayoshi, Benjamin D. Johnson, Mitchell Karmen, Conor Larison, Xiaojing Lin, Jianwei Lyu, Seppo Mattila, Takashi J. Moriya, Justin D. R. Pierel, Dávid Puskás, Armin Rest, George H. Rieke, Brant Robertson, Sepehr Salamat, Louis-Gregory Strolger , et al. (5 additional authors not shown)

Abstract: The James Webb Space Telescope (JWST) discovered 79 transients out to $z$$\sim$4.8 through the JADES Transient Survey (JTS), but the JTS did not find any $z$$>$5 transients. Here, we present the first photometric evidence of a $z$$>$5 transient/variable source with JWST. The source, AT 2023adya, resides in a $z_{\mathrm{spec}}$$=$5.274 galaxy in GOODS-N, which dimmed from $m_{\rm F356W}$$=$26.05… ▽ More The James Webb Space Telescope (JWST) discovered 79 transients out to $z$$\sim$4.8 through the JADES Transient Survey (JTS), but the JTS did not find any $z$$>$5 transients. Here, we present the first photometric evidence of a $z$$>$5 transient/variable source with JWST. The source, AT 2023adya, resides in a $z_{\mathrm{spec}}$$=$5.274 galaxy in GOODS-N, which dimmed from $m_{\rm F356W}$$=$26.05$\pm$0.02 mag to 26.24$\pm$0.02 mag in the rest-frame optical over approximately two rest-frame months, producing a clear residual signal in the difference image ($m_{\rm F356W}$$=$28.01$\pm$0.17 mag; SN$_\mathrm{var}$$=$6.09) at the galaxy center. Shorter-wavelength bands (F090W/F115W) show no rest-frame ultraviolet brightness change. Based on its rest-frame V-band absolute magnitude of M$_\mathrm{V}$$=$$-$18.48 mag, AT 2023adya could be any core-collapse supernova (SN) subtype or an SN Ia. However, due to low SN Ia rates at high redshift, the SN Ia scenario is unlikely. Alternatively, AT 2023adya may be a variable active galactic nucleus (AGN). However, the JWST NIRCam/Grism spectrum shows no broad H$α$ emission line (FWHM$=$130$\pm$26 km s$^{-1}$), disfavoring the variable AGN scenario. It is also unlikely that AT 2023adya is a tidal disruption event (TDE) because the TDE models matching the observed brightness changes have low event rates. Although it is not possible to determine AT 2023adya's nature based on the two-epoch single-band photometry alone, this discovery indicates that JWST can push the frontier of transient/variable science past $z$$=$5 and towards the epoch of reionization. △ Less

Submitted 31 July, 2025; v1 submitted 23 April, 2025; originally announced April 2025.

Comments: 13 pages, 4 figures, 1 table, accepted for publication in ApJ

Extreme Neutral Outflow in a non-AGN Quiescent Galaxy at z~1.3

Authors: Yang Sun, Zhiyuan Ji, George H. Rieke, Francesco D'Eugenio, Yongda Zhu, Fengwu Sun, Xiaojing Lin, Andrew J. Bunker, Jianwei Lyu, Pierluigi Rinaldi, Christopher N. A. Willmer

Abstract: We report the discovery of a substantial sodium doublet (Na D $λλ$5890, 5896Å)-traced neutral outflow in the quiescent galaxy JADES-GS-206183 at $z=1.317$. Its JWST/NIRSpec-MSA spectrum shows a deep, blueshifted Na D absorption, revealing a neutral outflow with $v_{\rm out}=828^{+79}_{-49}\,\mathrm{km\,s^{-1}}$ and a mass outflow rate of… ▽ More We report the discovery of a substantial sodium doublet (Na D $λλ$5890, 5896Å)-traced neutral outflow in the quiescent galaxy JADES-GS-206183 at $z=1.317$. Its JWST/NIRSpec-MSA spectrum shows a deep, blueshifted Na D absorption, revealing a neutral outflow with $v_{\rm out}=828^{+79}_{-49}\,\mathrm{km\,s^{-1}}$ and a mass outflow rate of $\log(\dot{M}_{\rm out}/\mathrm{M_{\odot}\,yr^{-1}})=2.40^{+0.11}_{-0.16}$. This outflow rate exceeds that of any neutral outflows identified beyond $z\sim1$ by the same line and is comparable with those in local galaxies with intensive star formation or luminous AGN. JADES-GS-206183 is also a peculiar quiescent galaxy with a spiral$+$bar morphology, high dust attenuation ($A_V=2.27\pm0.23$ mag). Paschen $α$ (Pa$α$) emission from the FRESCO NIRCam grism confirms its low star formation rate ($\mathrm{SFR_{Paα}}=10.78\pm 0.55\,\mathrm{M_{\odot}\,yr^{-1}}$), placing it 0.5 dex below the main-sequence ($\log(\mathrm{sSFR/yr^{-1}})=-10.2$). Despite the systematics introduced by different star formation history (SFH) priors, the SED modeling, combining HST-to-NIRCam photometry with the VLT/MUSE spectrum, suggests that JADES-GS-206183 experienced an older episode of star formation 0.5-2 Gyr ago and a possible rejuvenation within recent $\sim$10 Myr. Moreover, rest-frame optical lines indicate that the current AGN activity of JADES-GS-206183, if present, is also weak. Even though we tentatively detect a broad component of the H$α$ line, it likely traces an ionized outflow rather than an AGN. The results demonstrate that the Na D outflow in JADES-GS-206183 is highly unlikely to be driven by current star formation or nuclear activity. Instead, it may represent a long-lasting fossil outflow from past AGN activity, potentially co-triggered with the early phase of rejuvenation. △ Less

Submitted 12 December, 2025; v1 submitted 20 April, 2025; originally announced April 2025.

Comments: 24 pages, 12 figure, Accepted for publication in ApJ

A Potential Link between Nuclear Winds and Cold Gas Outflows on Kiloparsec Scales in Reionization-Era Quasars

Authors: Yongda Zhu, Marcia J. Rieke, Luis C. Ho, Yang Sun, George H. Rieke, Feng Yuan, Tom J. L. C. Bakx, George D. Becker, Jinyi Yang, Eduardo Bañados, Manuela Bischetti, Christopher Cain, Xiaohui Fan, Yoshinobu Fudamoto, Seyedazim Hashemi, Ryota Ikeda, Zhiyuan Ji, Xiangyu Jin, Weizhe Liu, Yichen Liu, Jianwei Lyu, Hai-Xia Ma, Tsutomu T. Takeuchi, Hideki Umehata, Feige Wang , et al. (1 additional authors not shown)

Abstract: Feedback from accreting supermassive black holes may regulate galaxy evolution, but statistical evidence linking nuclear winds to kiloparsec-scale cold gas outflows remains limited in the early universe. Here we report statistical evidence for such a connection in a sample of luminous quasars at $z \sim 5.5$. We compare stacked [C II] 158 $μ$m emission profiles from ALMA observations, which trace… ▽ More Feedback from accreting supermassive black holes may regulate galaxy evolution, but statistical evidence linking nuclear winds to kiloparsec-scale cold gas outflows remains limited in the early universe. Here we report statistical evidence for such a connection in a sample of luminous quasars at $z \sim 5.5$. We compare stacked [C II] 158 $μ$m emission profiles from ALMA observations, which trace galactic-scale neutral gas, for quasars with and without broad absorption lines (BALs) that indicate powerful nuclear winds on sub-kiloparsec scales. A total of 5 BAL and 11 non-BAL quasar spectra are included in the stacking analysis. The BAL quasar stack exhibits a potential blueshifted broad component in the [C II] line profile, with a velocity offset of $Δv_{\rm b} = -2.1 \times 10^2\,\rm km\,s^{-1}$ and a full width at half maximum of $1.18 \times 10^3\,\rm km\,s^{-1}$, whereas the non-BAL stack shows no obvious broad component. Using a conservative ``clean-stack'' selection that excludes quasars with partial [C II] spectral coverage, the BAL broad residual is reduced to a hint-level feature. We estimate that up to a few percent to one-quarter of the nuclear wind energy may be transferred to cold neutral gas on kiloparsec scales. Although the sample size is limited, these results suggest a potential link between BAL winds and cold gas feedback in quasar host galaxies. These results provide empirical motivation for future tests of how multiphase outflows relate to the diversity of quasar host properties, including $M_{\rm BH}/M_*$. △ Less

Submitted 24 March, 2026; v1 submitted 3 April, 2025; originally announced April 2025.

Comments: 18 pages, 9 figures, 1 table; Accepted for publication in ApJ

Deciphering the Nature of Virgil: An Obscured AGN Lurking Within an Apparently Normal Lyman-α Emitter During Cosmic Reionization

Authors: Pierluigi Rinaldi, Pablo G. Pérez-González, George H. Rieke, Jianwei Lyu, Francesco D'Eugenio, Zihao Wu, Stefano Carniani, Tobias J. Looser, Irene Shivaei, Leindert A. Boogaard, Tanio Diaz-Santos, Luis Colina, Göran Östlin, Stacey Alberts, Javier Álvarez-Márquez, Marianna Annuziatella, Manuel Aravena, Rachana Bhatawdekar, Andrew J. Bunker, Karina I. Caputi, Stéphane Charlot, Alejandro Crespo Gómez, Mirko Curti, Andreas Eckart, Steven Gillman , et al. (24 additional authors not shown)

Abstract: We present a comprehensive analysis of the MIRI Extremely Red Object Virgil, a Lyman-$α$ emitter at $z_{spec} = 6.6379 \pm 0.0035$ with the photometric properties of a Little Red Dot. Leveraging new JWST/MIRI imaging from the MIDIS and PAHSPECS programs, we confirm Virgil's extraordinary nature among galaxies in JADES/GOODS-South, exhibiting a strikingly red NIRCam-to-MIRI color (F444W $-$ F1500W… ▽ More We present a comprehensive analysis of the MIRI Extremely Red Object Virgil, a Lyman-$α$ emitter at $z_{spec} = 6.6379 \pm 0.0035$ with the photometric properties of a Little Red Dot. Leveraging new JWST/MIRI imaging from the MIDIS and PAHSPECS programs, we confirm Virgil's extraordinary nature among galaxies in JADES/GOODS-South, exhibiting a strikingly red NIRCam-to-MIRI color (F444W $-$ F1500W = $2.84\pm0.04$ mag). Deep NIRSpec/PRISM spectroscopy from the OASIS program offers key insights into the host galaxy, revealing properties of an average star-forming galaxy during Cosmic Reionization, such as a subsolar metallicity, low-to-moderate dust content, and a relatively high ionization parameter and electron temperature. By estimating the star formation rate of Virgil from UV and H$α$, we find evidence that the galaxy is either entering or fading out of a bursty episode. Although line-ratio diagnostics employed at high-$z$ would classify Virgil as an Active Galactic Nucleus (AGN), this classification becomes ambiguous once redshift evolution is considered. Nonetheless, Virgil occupies the same parameter space as recently confirmed AGNs at similar redshifts. The new deep MIRI data at 15 $μ$m reinforce the AGN nature of Virgil, as inferred from multiple spectral energy distribution (SED) fitting codes. Virgil's rising infrared SED and UV excess resemble those of Dust-Obscured Galaxies (DOGs) studied with Spitzer at Cosmic Noon, particularly blue-excess HotDOGs. Our results highlight the need for a multi-wavelength approach incorporating MIRI to uncover such extreme sources at $z\gtrsim6$ and to shed light on the interplay between galaxy evolution and early black hole growth during Cosmic Reionization. △ Less

Submitted 5 April, 2025; v1 submitted 2 April, 2025; originally announced April 2025.

Comments: 39 pages, 3 tables, 11 figures. Submitted to ApJ. Comments are welcome

The $M_{*}-M_{\rm BH}$ Relation Evolution from z $\sim$ 6 to the Present Epoch

Authors: Yang Sun, George H. Rieke, Jianwei Lyu, Meredith A. Stone, Zhiyuan Ji, Pierluigi Rinaldi, Christopher N. A. Willmer, Yongda Zhu

Abstract: The ratio between the stellar mass of a galaxy, $M_{*}$, and that of its central supermassive black hole (SMBH), $M_\bullet$, the ``Magorrian'' relationship, traces their coevolution. JWST observations have suggested significant evolution in $M_\bullet/M_{*}$ relative to local scaling relationships both in low-mass galaxies and in quasars at z $\ge$ 4. We test this possibility by (1) determining t… ▽ More The ratio between the stellar mass of a galaxy, $M_{*}$, and that of its central supermassive black hole (SMBH), $M_\bullet$, the ``Magorrian'' relationship, traces their coevolution. JWST observations have suggested significant evolution in $M_\bullet/M_{*}$ relative to local scaling relationships both in low-mass galaxies and in quasars at z $\ge$ 4. We test this possibility by (1) determining the preferred $M_\bullet/M_{*}$ scaling relation among those proposed locally; and (2) providing uniform host galaxy stellar mass estimates. These steps reduce the prominence of the reported evolution. We then apply Monte Carlo simulations to account for observational biases. We still find a significant increase over the local scaling relation in $M_\bullet/M_{*}$ for z $\ge$ 4 SMBHs in very low-mass galaxies ($\log(M_*/M_{\odot})<10$). However, similarly high values of $M_\bullet/M_{*}$ are also found in low mass galaxies at $z \sim$ 0.5 to 3 that may be common at cosmic noon. Nonetheless, galaxies with similar behavior are rare locally and not accounted for in the local scaling relations. In contrast, z $\sim$ 6 quasars can have $M_\bullet/M_{*}$ well above the local relation value, but they can be explained as extreme cases still within the scaling relation for their higher mass host galaxies. Black holes in some of them and in the low-mass systems may be undergoing very high accretion episodes that result in high $M_\bullet/M_{*}$ but that will be followed by quiescent periods when growth of the host drives the systems toward more typical $M_\bullet/M_{*}$ values. △ Less

Submitted 7 March, 2025; v1 submitted 5 March, 2025; originally announced March 2025.

Comments: 20 pages, 7 figures, resubmitted to ApJ based on reviewer report

Unveiling the Aromatic and Aliphatic Universe at Redshifts $z\sim$0.2--0.5 with JWST NIRCam/WFSS

Authors: Jianwei Lyu, Xuejuan Yang, Aigen Li, Fengwu Sun, George H. Rieke, Stacey Alberts, Irene Shivaei

Abstract: Utilizing deep NIRCam/WFSS data from JWST's FRESCO program, we spectroscopically survey the 3.3 $μm$ aromatic and 3.4 $μm$ aliphatic C--H stretching emission bands of polycyclic aromatic hydrocarbon (PAH) molecules in galaxies at redshifts $z$$\sim$0.2--0.5. Unlike pre-JWST studies, largely limited to infrared (IR)-bright galaxies ($L_{\rm IR}\gtrsim10^{11}~L_\odot$) at $z\lesssim0.1$, we probe 20… ▽ More Utilizing deep NIRCam/WFSS data from JWST's FRESCO program, we spectroscopically survey the 3.3 $μm$ aromatic and 3.4 $μm$ aliphatic C--H stretching emission bands of polycyclic aromatic hydrocarbon (PAH) molecules in galaxies at redshifts $z$$\sim$0.2--0.5. Unlike pre-JWST studies, largely limited to infrared (IR)-bright galaxies ($L_{\rm IR}\gtrsim10^{11}~L_\odot$) at $z\lesssim0.1$, we probe 200 galaxies down to $L_{\rm IR}$$\sim$$10^{8.5}$--$10^{10}~L_\odot$ well beyond the local Universe. The 3.3 $μm$ emission is detected at $\geq$3-$σ$ in 88 out of 187 galaxies, correlating tightly with galaxy IR luminosity and star formation rate (SFR) and confirming the 3.3 $μm$ PAH as a viable SFR tracer. Despite a large scatter, the 3.3 $μm$-to-IR luminosity ratio ($L_{3.3}/L_{\rm IR}$) exhibits a strong metallicity dependence with a drop of $L_{3.3}/L_{\rm IR}$ by a factor of $\gtrsim10$ at 12+log(O/H)$\sim$8.4--8.5 towards lower metallicities. The 3.4 $μm$ emission is detected in 37 out of 159 galaxies, with the 3.4 $μm$-to-3.3 $μm$ luminosity ratio ($L_{3.4}/L_{3.3}$) spanning from $\sim$0.05 to $\sim$0.58 (median $\sim$0.19), corresponding to PAH aliphatic fractions of $\sim$0.78%--8.3% (median $\sim$2.9%) in terms of fractional carbon atoms in aliphatic units. While $L_{3.4}/L_{3.3}$ does not depend significantly on redshift, stellar mass, metallicity, or galaxy morphology, it does decrease with various SFR tracers, suggesting that ultraviolet photons in active star-forming regions may strip aliphatic sidegroups from PAH molecules. Our study showcases the unique power of JWST's NIRCam/WFSS to systematically map PAH aromatic and aliphatic content in statistically significant, less-biased galaxy samples, providing critical insights into PAH chemistry and its connection to galaxy properties. △ Less

Submitted 5 May, 2025; v1 submitted 25 February, 2025; originally announced February 2025.

Comments: 15 pages, 8 figures, 2 tables; Accepted for publication to The Astrophysical Journal (ApJ)

A SPectroscopic survey of biased halos In the Reionization Era (ASPIRE): Spectroscopically Complete Census of Obscured Cosmic Star Formation Rate Density at $z=4-6$

Authors: Fengwu Sun, Feige Wang, Jinyi Yang, Jaclyn B. Champagne, Roberto Decarli, Xiaohui Fan, Eduardo Bañados, Zheng Cai, Luis Colina, Eiichi Egami, Joseph F. Hennawi, Xiangyu Jin, Hyunsung D. Jun, Yana Khusanova, Mingyu Li, Zihao Li, Xiaojing Lin, Weizhe Liu, Romain A. Meyer, Maria A. Pudoka, George H. Rieke, Yue Shen, Wei Leong Tee, Bram Venemans, Fabian Walter , et al. (3 additional authors not shown)

Abstract: We present a stringent measurement of the dust-obscured star-formation rate density (SFRD) at $z=4-6$ from the ASPIRE JWST Cycle-1 medium and ALMA Cycle-9 large program. We obtained JWST/NIRCam grism spectroscopy and ALMA 1.2-mm continuum map along 25 independent quasar sightlines, covering a total survey area of $\sim$35 arcmin$^2$ where we search for dusty star-forming galaxies (DSFGs) at… ▽ More We present a stringent measurement of the dust-obscured star-formation rate density (SFRD) at $z=4-6$ from the ASPIRE JWST Cycle-1 medium and ALMA Cycle-9 large program. We obtained JWST/NIRCam grism spectroscopy and ALMA 1.2-mm continuum map along 25 independent quasar sightlines, covering a total survey area of $\sim$35 arcmin$^2$ where we search for dusty star-forming galaxies (DSFGs) at $z = 0 - 7$. We identify eight DSFGs in seven fields at $z=4-6$ through the detection of H$α$ or [O III] $λ$5008 lines, including fainter lines such as H$β$, [O III] $λ$4960, [N II] $λ$6585, [S II] $λλ$6718,6733 for six sources. With this spectroscopically complete DSFG sample at $z=4-6$ and negligible impact from cosmic variance (shot noise), we measure the infrared luminosity function (IRLF) down to $L_\mathrm{IR} \sim 2\times10^{11}$ $L_\odot$. We find flattening of IRLF at $z=4-6$ towards the faint end (power-law slope $α= 0.59_{-0.45}^{+0.39}$). We determine the dust-obscured cosmic SFRD at this epoch as $\log[ρ_\mathrm{SFR,IR} / (\mathrm{M}_\odot\,\mathrm{yr}^{-1}\,\mathrm{Mpc}^{-3})] = -1.52_{-0.13}^{+0.14}$. This is significantly higher than previous determination using ALMA data in the Hubble Ultra Deep Field, which is void of DSFGs at $z=4-6$ because of strong cosmic variance (shot noise). We conclude that the majority ($66\pm7$%) of cosmic star formation at $z \sim 5$ is still obscured by dust. We also discuss the uncertainty of SFRD propagated from far-IR spectral energy distribution and IRLF at the bright end, which will need to be resolved with future ALMA and JWST observations. △ Less

Submitted 9 December, 2024; originally announced December 2024.

Comments: 27 pages, 13 figures, 3 tables. Accepted for publication in ApJ

Fading Light, Fierce Winds: JWST Snapshot of a Sub-Eddington Quasar at Cosmic Dawn

Authors: Jianwei Lyu, George H. Rieke, Meredith Stone, Jane Morrison, Stacey Alberts, Xiangyu Jin, Yongda Zhu, Weizhe Liu, Jinyi Yang

Abstract: The majority of most luminous quasars during the epoch of reionization accrete near or above the Eddington limit, marking the vigorous growth of primitive supermassive black holes (SMBHs). However, their subsequent evolution and environmental impact remain poorly characterized. We present JWST/NIRSpec prism IFU observations of HSC J2239+0207, a low-luminosity quasar at $z\sim6.25$ likely in a late… ▽ More The majority of most luminous quasars during the epoch of reionization accrete near or above the Eddington limit, marking the vigorous growth of primitive supermassive black holes (SMBHs). However, their subsequent evolution and environmental impact remain poorly characterized. We present JWST/NIRSpec prism IFU observations of HSC J2239+0207, a low-luminosity quasar at $z\sim6.25$ likely in a late stage of mass assembly with an overmassive SMBH relative to its host galaxy. Using H$β$ and H$α$ broad emission lines, we estimate an SMBH mass $M_{\rm BH}\sim3\times10^8~M_{\odot}$ and confirm its sub-Eddington accretion at $λ_{\rm Edd}\sim0.4$. Strong FeII emission and a proximity zone of typical size suggest a metal-rich, highly evolved system. In the far-UV, this quasar presents strong broad-absorption-line features, indicative of high-velocity winds ($ν\sim10^4~{\rm km/s}$). Meanwhile, minimal dust reddening is inferred from the quasar continuum and broad-line Balmer decrement, suggesting little dust along the polar direction. Most interestingly, we identify a gas companion $\sim$5 kpc from the quasar with a high [OIII]/H$β$ ratio ($\gtrsim10$), likely representing outflowing gas blown away by AGN feedback. These results highlight HSC J2239+0207 as a likely fading quasar in transition, providing rare insights into SMBH evolution, AGN feedback, and AGN-galaxy interactions in the early Universe. △ Less

Submitted 14 February, 2025; v1 submitted 5 December, 2024; originally announced December 2024.

Comments: 12 pages, 5 figures; Accepted for publication in ApJL

Journal ref: ApJL, 981, L20 (2025)

Not Just a Dot: the complex UV morphology and underlying properties of Little Red Dots

Authors: P. Rinaldi, N. Bonaventura, G. H. Rieke, S. Alberts, K. I. Caputi, W. M. Baker, S. Baum, R. Bhatawdekar, A. J. Bunker, S. Carniani, E. Curtis-Lake, F. D'Eugenio, E. Egami, Z. Ji, K. Hainline, J. M. Helton, X. Lin, J. Lyu, B. D. Johnson, Z. Ma, R. Maiolino, P. G. Pérez-González, M. Rieke, B. E. Robertson, I. Shivaei , et al. (9 additional authors not shown)

Abstract: We analyze 99 photometrically selected Little Red Dots (LRDs) at $z \approx 4-8$ in the GOODS fields, leveraging ultra-deep JADES NIRCam short-wavelength (SW) data. We examine the morphology of 30 LRDs, while the remaining 69 appear predominantly compact, with sizes $\leq 400$ pc and no extended components even in stacked SW images. However, their unresolved nature may partly reflect current depth… ▽ More We analyze 99 photometrically selected Little Red Dots (LRDs) at $z \approx 4-8$ in the GOODS fields, leveraging ultra-deep JADES NIRCam short-wavelength (SW) data. We examine the morphology of 30 LRDs, while the remaining 69 appear predominantly compact, with sizes $\leq 400$ pc and no extended components even in stacked SW images. However, their unresolved nature may partly reflect current depth limitations, which could prevent the detection of faint diffuse components. Among the 30 morphologically analyzed LRDs, 50% show multiple associated components, while the rest exhibit highly asymmetric structures, despite appearing as single sources. This diversity in rest-frame UV morphologies may point to interactions or strong internal feedback. We find median stellar masses of $\log_{10}(M_{\star}/M_{\odot}) = 9.07_{-0.08}^{+0.11}$ for pure stellar models with $A_{V} \approx 1.16^{+0.11}{-0.21}$ mag, and $\log{10}(M_{\star}/M_{\odot}) = 9.67^{+0.17}{-0.27}$ for models including AGNs with $A{V} \approx 2.74^{+0.55}_{-0.71}$ mag, in line with recent studies suggesting higher masses and dust content for AGN-fitted LRDs. NIRSpec spectra are available for 15 sources, six of which are also in the morphological sample. Broad H$α$ is detected in 40% (FWHM = 1200-2900 km/s), and one source shows broad H$β$ emission. Emission line ratios indicate a composite nature, consistent with both AGN and stellar processes. Altogether, these results suggest that LRDs are a mixed population, and their rest-frame UV morphology reflects this complexity. Morphological studies of larger samples could provide a new way to understand what drives their properties and evolution. △ Less

Submitted 2 October, 2025; v1 submitted 21 November, 2024; originally announced November 2024.

Comments: 28 pages, 10 figures, 3 tables. Accepted for publication in ApJ

Deep Search for a scattered light dust halo around Vega with the Hubble Space Telescope

Authors: Schuyler G. Wolff, András Gáspár, George H. Rieke, Jarron M. Leisenring, Kate Su, David Wilner, Luca Matrà, Marie Ygouf, Nicholas P. Ballering

Abstract: We present a provisory scattered light detection of the Vega debris disk using deep Hubble Space Telescope coronagraphy (PID 16666). At only 7.7 parsecs, Vega is immensely important in debris disk studies both for its prominence and also because it allows the highest physical resolution among all debris systems relative to temperature zones around the star. We employ the STIS coronagraph's widest… ▽ More We present a provisory scattered light detection of the Vega debris disk using deep Hubble Space Telescope coronagraphy (PID 16666). At only 7.7 parsecs, Vega is immensely important in debris disk studies both for its prominence and also because it allows the highest physical resolution among all debris systems relative to temperature zones around the star. We employ the STIS coronagraph's widest wedge position and classical Reference Differential Imaging to achieve among the lowest surface brightness sensitivities to date ($\sim 4\,μJy/arcsec^{2}$) at wide separations using 32 orbits in Cycle 29. We detect a halo extending from the inner edge of our effective inner working angle at $10^{\prime\prime}.5$ out to the photon noise floor at $30^{\prime\prime}$ (80 - 230 au). The face-on orientation of the system and the lack of a perfectly color-matched PSF star have provided significant challenges to the reductions, particularly regarding artifacts from the imperfect color matching. However, we find that a halo of small dust grains provides the best explanation for the observed signal. Unlike Fomalhaut (a close twin to Vega in luminosity, distance, and age), there is no clear distinction in scattered light between the parent planetesimal belt observed with ALMA and the extended dust halo. These HST observations complement JWST GTO Cycle 1 observations of the system with NIRCam and MIRI. △ Less

Submitted 12 November, 2024; v1 submitted 31 October, 2024; originally announced October 2024.

Journal ref: 2024 AJ 168 236

Imaging of the Vega Debris System using JWST/MIRI

Authors: Kate Y. L. Su, Andras Gaspar, George H. Rieke, Renu Malhotra, Luca Matra, Schuyler Grace Wolff, Jarron M. Leisenring, Charles Beichman, Marie Ygouf

Abstract: We present images of the Vega planetary debris disk obtained at 15.5, 23, and 25.5 microns with the Mid-Infrared Instrument (MIRI) on JWST. The debris system is remarkably symmetric and smooth, and centered accurately on the star. There is a broad Kuiper-belt-analog ring at 80 to 170 au that coincides with the planetesimal belt detected with ALMA at 1.34 mm. The interior of the broad belt is fille… ▽ More We present images of the Vega planetary debris disk obtained at 15.5, 23, and 25.5 microns with the Mid-Infrared Instrument (MIRI) on JWST. The debris system is remarkably symmetric and smooth, and centered accurately on the star. There is a broad Kuiper-belt-analog ring at 80 to 170 au that coincides with the planetesimal belt detected with ALMA at 1.34 mm. The interior of the broad belt is filled with warm debris that shines most efficiently at mid-infrared along with a shallow flux dip/gap at 60 au from the star. These qualitative characteristics argue against any Saturn-mass planets orbiting the star outside of about 10 au assuming the unseen planet would be embedded in the very broad planetesimal disk from a few to hundred au. We find that the distribution of dust detected interior to the broad outer belt is consistent with grains being dragged inward by the Poynting-Robertson effect. Tighter constraints can be derived for planets in specific locations, for example any planet shepherding the inner edge of the outer belt is likely to be less than 6 Earth masses. The disk surface brightness profile along with the available infrared photometry suggest a disk inner edge near 3-5 au, disconnected from the sub-au region that gives rise to the hot near-infrared excess. The gap between the hot, sub-au zone and the inner edge of the warm debris might be shepherded by a modest mass, Neptune-size planet. △ Less

Submitted 31 October, 2024; originally announced October 2024.

Comments: accepted for publication in ApJ

Searching for Planets Orbiting Vega with the James Webb Space Telescope

Authors: Charles Beichman, Geoffrey Bryden, Jorge Llop-Sayson, Marie Ygouf, Alexandra Greenbaum, Jarron Leisenring, Andras Gaspar, John Krist, George Rieke, Schuyler Wolff, Kate Su, Klaus Hodapp, Michael Meyer, Doug Kelly, Martha Boyer, Doug Johnstone, Scott Horner, Marcia Rieke

Abstract: The most prominent of the IRAS debris disk systems, $α$ Lyrae (Vega), at a distance of 7.7 pc, has been observed by both the NIRCam and MIRI instruments on the James Webb Space Telescope (JWST). This paper describes NIRCam coronagraphic observations which have achieved F444W contrast levels of 3$\times10^{-7}$ at 1\arcsec\ (7.7 au), 1$\times10^{-7}$ at 2\arcsec\ (15 au) and few $\times 10^{-8}$ be… ▽ More The most prominent of the IRAS debris disk systems, $α$ Lyrae (Vega), at a distance of 7.7 pc, has been observed by both the NIRCam and MIRI instruments on the James Webb Space Telescope (JWST). This paper describes NIRCam coronagraphic observations which have achieved F444W contrast levels of 3$\times10^{-7}$ at 1\arcsec\ (7.7 au), 1$\times10^{-7}$ at 2\arcsec\ (15 au) and few $\times 10^{-8}$ beyond 5\arcsec\ (38 au), corresponding to masses of $<$ 3, 2 and 0.5 MJup for a system age of 700 Myr. Two F444W objects are identified in the outer MIRI debris disk, around 48 au. One of these is detected by MIRI, appears to be extended and has a spectral energy distribution similar to those of distant extragalactic sources. The second one also appears extended in the NIRCam data suggestive of an extragalactic nature.The NIRCam limits within the inner disk (1\arcsec\ --10\arcsec) correspond to a model-dependent masses of 2$\sim$3 \mj. \citet{Su2024} argue that planets larger even 0.3 MJup would disrupt the smooth disk structure seen at MIRI wavelengths. Eight additional objects are found within 60\arcsec\ of Vega, but none has astrometric properties or colors consistent with planet candidates. These observations reach a level consistent with expected Jeans Mass limits. Deeper observations achieving contrast levels $<10^{-8}$ outside of $\sim$4\arcsec\ and reaching masses below that of Saturn are possible, but may not reveal a large population of new objects. △ Less

Submitted 11 December, 2024; v1 submitted 21 October, 2024; originally announced October 2024.

Comments: 19 pages, 12 figures. accepted for Astronomical Journal

SMILES: Potentially Higher Ionizing Photon Production Efficiency in Overdense Regions

Authors: Yongda Zhu, Stacey Alberts, Jianwei Lyu, Jane Morrison, George H. Rieke, Yang Sun, Jakob M. Helton, Zhiyuan Ji, Rachana Bhatawdekar, Nina Bonaventura, Andrew J. Bunker, Xiaojing Lin, Marcia J. Rieke, Pierluigi Rinaldi, Irene Shivaei, Christopher N. A. Willmer, Junyu Zhang

Abstract: The topology of reionization and the environments where galaxies efficiently produce ionizing photons are key open questions. For the first time, we investigate the trend between ionizing photon production efficiency, $ξ_{\rm ion}$, and galaxy overdensity, $\log(1+δ)$. We analyze the ionizing properties of 79 galaxies between $1.0 < z < 5.2$ using JWST NIRSpec medium-resolution spectra from the Sy… ▽ More The topology of reionization and the environments where galaxies efficiently produce ionizing photons are key open questions. For the first time, we investigate the trend between ionizing photon production efficiency, $ξ_{\rm ion}$, and galaxy overdensity, $\log(1+δ)$. We analyze the ionizing properties of 79 galaxies between $1.0 < z < 5.2$ using JWST NIRSpec medium-resolution spectra from the Systematic Mid-infrared Instrument (MIRI) Legacy Extragalactic Survey (SMILES) program. Among these, 67 galaxies have H$α$ coverage, spanning $1.0 < z < 3.1$. The galaxy overdensity, $\log(1+δ)$, is measured using the JADES photometric catalog, which covers the SMILES footprint. For the subset with H$α$ coverage, we find that $\logξ_{\rm ion}$ is positively correlated with $\log(1+δ)$, with a slope of $0.94_{-0.46}^{+0.46}$. Additionally, the mean $ξ_{\rm ion}$ for galaxies in overdense regions ($\log(1+δ) > 0.1$) is 2.43 times that of galaxies in lower density regions ($\log(1+δ) < 0.1$). This strong trend is found to be independent of redshift evolution. Furthermore, our results confirm the robust correlations between $ξ_{\rm ion}$ and the rest-frame equivalent widths of the [O III] or H$α$ emission lines. Our results suggest that galaxies in high-density regions are efficient producers of ionizing photons. △ Less

Submitted 5 May, 2025; v1 submitted 18 October, 2024; originally announced October 2024.

Comments: 17 pages. Accepted for publication in ApJ

Extended hot dust emission around the earliest massive quiescent galaxy

Authors: Zhiyuan Ji, Christina C. Williams, George H. Rieke, Jianwei Lyu, Stacey Alberts, Fengwu Sun, Jakob M. Helton, Marcia Rieke, Irene Shivaei, Francesco D'Eugenio, Sandro Tacchella, Brant Robertson, Yongda Zhu, Roberto Maiolino, Andrew J. Bunker, Yang Sun, Christopher N. A. Willmer

Abstract: A major unsolved problem in galaxy evolution is the early appearance of massive quiescent galaxies that no longer actively form stars only $ \sim 1$ billion years after the Big Bang. Their high stellar masses and extremely compact structure indicate that they formed through rapid bursts of star formation between redshift $z \sim 6-11$. Theoretical models of galaxy evolution cannot explain their hi… ▽ More A major unsolved problem in galaxy evolution is the early appearance of massive quiescent galaxies that no longer actively form stars only $ \sim 1$ billion years after the Big Bang. Their high stellar masses and extremely compact structure indicate that they formed through rapid bursts of star formation between redshift $z \sim 6-11$. Theoretical models of galaxy evolution cannot explain their high number density, rapid growth and truncation of star formation at such early times, which likely requires extreme feedback to destroy the cold interstellar medium (the fuel for star formation). We report the discovery of a significant reservoir of hot dust in one of the most distant known examples at $z = 4.658$, GS-9209. The dust was identified using JWST's Mid-Infrared Instrument (MIRI), whose unprecedented sensitivity and high spatial resolution, for the first time, firmly show that this dust is significantly more extended than the stars by $\gtrsim 3$ times. We find that the dust has preferentially been evacuated or diluted in the galaxy center. Our analysis finds that the extended hot dust emission is consistent with recent heating by a younger and more spatially extended generation of star formation. This reveals that the earliest quiescent galaxies did not form in a single rapid burst; instead, similar to galaxy growth at later times, the center formed first with star formation continuing in an extended envelope. The growth of this galaxy is truncating from the inside out, consistent with central gas depletion from early AGN feedback. △ Less

Submitted 25 September, 2024; originally announced September 2024.

Comments: Submitted

A Systematic Search for Galaxies with Extended Emission Line and Potential Outflows in JADES Medium-Band Images

Authors: Yongda Zhu, Marcia J. Rieke, Zhiyuan Ji, Charlotte Simmonds, Fengwu Sun, Yang Sun, Stacey Alberts, Rachana Bhatawdekar, Andrew J. Bunker, Phillip A. Cargile, Stefano Carniani, Anna de Graaff, Kevin Hainline, Jakob M. Helton, Gareth C. Jones, Jianwei Lyu, George H. Rieke, Pierluigi Rinaldi, Brant Robertson, Jan Scholtz, Hannah Übler, Christina C. Williams, Christopher N. A. Willmer

Abstract: For the first time, we present a systematic search for galaxies with extended emission line and potential outflow features using \textit{JWST} medium-band images in the GOODS-S field. This is done by comparing the morphology in medium-band images to adjacent continuum and UV bands. We look for galaxies that have a maximum extent 50\% larger, an excess area 30\% greater, or an axis ratio difference… ▽ More For the first time, we present a systematic search for galaxies with extended emission line and potential outflow features using \textit{JWST} medium-band images in the GOODS-S field. This is done by comparing the morphology in medium-band images to adjacent continuum and UV bands. We look for galaxies that have a maximum extent 50\% larger, an excess area 30\% greater, or an axis ratio difference of more than 0.3 in the medium band compared to the reference bands. After visual inspection, we find 326 candidate galaxies at $1.4 < z < 8.4$, with a peak in the population near cosmic noon, benefiting from the good coverage of the medium-band filters. By fitting their SEDs, we find that the candidate galaxies are at least 20\% more bursty in their star-forming activity and have 50\% more young stellar populations compared to a control sample selected based on the continuum band flux. Additionally, these candidates exhibit a significantly higher production rate of ionizing photons. We further find that candidates hosting known AGN produce extended emission that is more anisotropic compared to non-AGN candidates. A few of our candidates have been spectroscopically confirmed to have prominent outflow signatures through NIRSpec observations, showcasing the robustness of the photometric selection. Future spectroscopic follow-up will better help verify and characterize the kinematics and chemical properties of these systems. △ Less

Submitted 5 May, 2025; v1 submitted 17 September, 2024; originally announced September 2024.

Comments: 23 pages, 12 figures, 2 tables. Accepted for publication in ApJ

The James Webb Space Telescope Absolute Flux Calibration. II. Mid-Infrared Instrument Imaging and Coronagraphy

Authors: Karl D. Gordon, G. C. Sloan, Macarena Garcia Marin, Mattia Libralato, George Rieke, Jonathan A. Aguilar, Ralph Bohlin, Misty Cracraft, Marjorie Decleir, Andras Gaspar, Sarah Kendrew, David R. Law, Alberto Noriega-Crespo, Michael Regan

Abstract: The absolute flux calibration of the Mid-Infrared Instrument Imaging and Coronagraphy is based on observations of multiple stars taken during the first 2.5 years of JWST operations. The observations were designed to ensure that the flux calibration is valid for a range of flux densities, different subarrays, and different types of stars. The flux calibration was measured by combining observed aper… ▽ More The absolute flux calibration of the Mid-Infrared Instrument Imaging and Coronagraphy is based on observations of multiple stars taken during the first 2.5 years of JWST operations. The observations were designed to ensure that the flux calibration is valid for a range of flux densities, different subarrays, and different types of stars. The flux calibration was measured by combining observed aperture photometry corrected to infinite aperture with predictions based on previous observations and models of stellar atmospheres. A subset of these observations were combined with model point-spread-functions to measure the corrections to infinite aperture. Variations in the calibration factor with time, flux density, background level, type of star, subarray, integration time, rate, and well depth were investigated, and the only significant variations were with time and subarray. Observations of the same star taken approximately every month revealed a modest time-dependent response loss seen mainly at the longest wavelengths. This loss is well characterized by a decaying exponential with a time constant of ~200 days. After correcting for the response loss, the band-dependent scatter around the corrected average (aka repeatability) was found to range from 0.1 to 1.2%. Signals in observations taken with different subarrays can be lower by up to 3.4% compared to FULL frame. After correcting for the time and subarray dependencies, the scatter in the calibration factors measured for individual stars ranges from 1 to 4% depending on the band. The formal uncertainties on the flux calibration averaged for all observations are 0.3 to 1.0%, with longer-wavelength bands generally having larger uncertainties. △ Less

Submitted 27 November, 2024; v1 submitted 16 September, 2024; originally announced September 2024.

Comments: 26 pages, 17 figures, AJ, in press (updated to add a missing author and fix A_cor values in Table 4)

No evidence for a significant evolution of $M_{\bullet}$-$M_*$ relation in massive galaxies up to z$\sim$4

Authors: Yang Sun, Jianwei Lyu, George H. Rieke, Zhiyuan Ji, Fengwu Sun, Yongda Zhu, Andrew J. Bunker, Phillip A. Cargile, Chiara Circosta, Francesco D'Eugenio, Eiichi Egami, Kevin Hainline, Jakob M. Helton, Pierluigi Rinaldi, Brant E. Robertson, Jan Scholtz, Irene Shivaei, Meredith A. Stone, Sandro Tacchella, Christina C. Williams, Christopher N. A. Willmer, Chris Willott

Abstract: Over the past two decades, tight correlations between black hole masses ($M_\bullet$) and their host galaxy properties have been firmly established for massive galaxies ($\log(M_*/M_{\odot})\gtrsim10$) at low-$z$ ($z<1$), indicating coevolution of supermassive black holes and galaxies. However, the situation at high-$z$, especially beyond cosmic noon ($z\gtrsim2.5$), is controversial. With a combi… ▽ More Over the past two decades, tight correlations between black hole masses ($M_\bullet$) and their host galaxy properties have been firmly established for massive galaxies ($\log(M_*/M_{\odot})\gtrsim10$) at low-$z$ ($z<1$), indicating coevolution of supermassive black holes and galaxies. However, the situation at high-$z$, especially beyond cosmic noon ($z\gtrsim2.5$), is controversial. With a combination of \emph{JWST} NIRCam/wide field slitless spectroscopy (WFSS) from FRESCO, CONGRESS and deep multi-band NIRCam/image data from JADES in the GOODS fields, we study the black hole to galaxy mass relation at z$\sim$1--4. After identifying 18 broad-line active galactic nuclei (BL AGNs) at $1<z<4$ (with 8 at $z>2.5$) from the WFSS data, we measure their black hole masses based on broad near-infrared lines (Pa $α$, Pa $β$, and He\,I $λ$10833\,Å), and constrain their stellar masses ($M_{*}$) from AGN-galaxy image decomposition or SED decomposition. Taking account of the observational biases, the intrinsic scatter of the $M_{\bullet}-M_{*}$ relation, and the errors in mass measurements, we find no significant difference in the $M_{\bullet}/M_{*}$ ratio for 2.5 $< $ z $ <$ 4 compared to that at lower redshifts ($1 < z < 2.5$), suggesting no evolution of the $M_{\bullet} - M_{*}$ relation at $\log(M_*/M_{\odot})\gtrsim10$ up to z$\sim$4. △ Less

Submitted 13 November, 2024; v1 submitted 10 September, 2024; originally announced September 2024.

Comments: 23 pages, 12 figures, submitted to AAS Journals

JADES Ultra-red Flattened Objects: Morphologies and Spatial Gradients in Color and Stellar Populations

Authors: Justus L. Gibson, Erica Nelson, Christina C. Williams, Sedona H. Price, Katherine E. Whitaker, Katherine A. Suess, Anna de Graaff, Benjamin D. Johnson, Andrew J. Bunker, William M. Baker, Rachana Bhatawdekar, Kristan Boyett, Stephane Charlot, Emma Curtis-Lake, Daniel J. Eisenstein, Kevin Hainline, Ryan Hausen, Roberto Maiolino, George Rieke, Marcia Rieke, Brant Robertson, Sandro Tacchella, Chris Willott

Abstract: One of the more surprising findings after the first year of JWST observations is the large number of spatially extended galaxies (ultra-red flattened objects, or UFOs) among the optically-faint galaxy population otherwise thought to be compact. Leveraging the depth and survey area of the JADES survey, we extend observations of the optically-faint galaxy population to an additional 112 objects, 56… ▽ More One of the more surprising findings after the first year of JWST observations is the large number of spatially extended galaxies (ultra-red flattened objects, or UFOs) among the optically-faint galaxy population otherwise thought to be compact. Leveraging the depth and survey area of the JADES survey, we extend observations of the optically-faint galaxy population to an additional 112 objects, 56 of which are well-resolved in F444W with effective sizes, $R_e > 0.25''$, more than tripling previous UFO counts. These galaxies have redshifts around $2 < z < 4$, high stellar masses ($\mathrm{log(M_*/M_{\odot})} \sim 10-11$), and star-formation rates around $\sim 100-1000 \mathrm{M_{\odot}/yr}$. Surprisingly, UFOs are red across their entire extents which spatially resolved analysis of their stellar populations shows is due to large values of dust attenuation (typically $A_V > 2$ mag even at large radii). Morphologically, the majority of our UFO sample tends to have low Sérsic indices ($n \sim 1$) suggesting these large, massive, optically faint galaxies have little contribution from a bulge in F444W. Further, a majority have axis-ratios between $0.2 < q < 0.4$, which Bayesian modeling suggests that their intrinsic shapes are consistent with being a mixture of inclined disks and prolate objects with little to no contribution from spheroids. While kinematic constraints will be needed to determine the true intrinsic shapes of UFOs, it is clear that an unexpected population of large, disky or prolate objects contributes significantly to the population of optically faint galaxies. △ Less

Submitted 5 August, 2024; originally announced August 2024.

Comments: 24 pages, 13 figures; accepted for publication in The Astrophysical Journal

The JADES Transient Survey: Discovery and Classification of Supernovae in the JADES Deep Field

Authors: Christa DeCoursey, Eiichi Egami, Justin D. R. Pierel, Fengwu Sun, Armin Rest, David A. Coulter, Michael Engesser, Matthew R. Siebert, Kevin N. Hainline, Benjamin D. Johnson, Andrew J. Bunker, Phillip A. Cargile, Stephane Charlot, Wenlei Chen, Mirko Curti, Shea DeFour-Remy, Daniel J. Eisenstein, Ori D. Fox, Suvi Gezari, Sebastian Gomez, Jacob Jencson, Bhavin A. Joshi, Sanvi Khairnar, Jianwei Lyu, Roberto Maiolino , et al. (13 additional authors not shown)

Abstract: The JWST Advanced Deep Extragalactic Survey (JADES) is a multi-cycle JWST program that has taken among the deepest near-/mid-infrared images to date (down to $\sim$30 ABmag) over $\sim$25 arcmin$^2$ in the GOODS-S field in two sets of observations with one year of separation. This presented the first opportunity to systematically search for transients, mostly supernovae (SNe), out to $z$$>$2. We f… ▽ More The JWST Advanced Deep Extragalactic Survey (JADES) is a multi-cycle JWST program that has taken among the deepest near-/mid-infrared images to date (down to $\sim$30 ABmag) over $\sim$25 arcmin$^2$ in the GOODS-S field in two sets of observations with one year of separation. This presented the first opportunity to systematically search for transients, mostly supernovae (SNe), out to $z$$>$2. We found 79 SNe: 38 at $z$$<$2, 23 at 2$<$$z$$<$3, 8 at 3$<$$z$$<$4, 7 at 4$<$$z$$<$5, and 3 with undetermined redshifts, where the redshifts are predominantly based on spectroscopic or highly reliable JADES photometric redshifts of the host galaxies. At this depth, the detection rate is $\sim$1-2 per arcmin$^2$ per year, demonstrating the power of JWST as a supernova discovery machine. We also conducted multi-band follow-up NIRCam observations of a subset of the SNe to better constrain their light curves and classify their types. Here, we present the survey, sample, search parameters, spectral energy distributions (SEDs), light curves, and classifications. Even at $z$$\geq$2, the NIRCam data quality is high enough to allow SN classification via multi-epoch light-curve fitting with confidence. The multi-epoch SN sample includes a Type Ia SN at $z_{\mathrm{spec}}$$=$2.90, Type IIP SN at $z_{\mathrm{spec}}$$=$3.61, and a Type Ic-BL SN at $z_{\mathrm{spec}}$$=$2.83. We also found that two $z$$\sim$16 galaxy candidates from the first imaging epoch were actually transients that faded in the second epoch, illustrating the possibility that moderate/high-redshift SNe could mimic high-redshift dropout galaxies. △ Less

Submitted 27 January, 2025; v1 submitted 7 June, 2024; originally announced June 2024.

Comments: 46 pages, 16 figures, 16 tables. Accepted by ApJ. Appendix A (64 MB) is available at https://drive.google.com/file/d/1xs5jXUVOvdDPgdghK72KR1FMGvPcK7dv/view?usp=sharing . Appendix B (81 MB) is available at https://drive.google.com/file/d/18ImLT80pQdPzXCZA-KEy21DaE2CQiGz1/view?usp=sharing