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The majority of massive disk galaxies in the local Universe show a stellar barred structure in their central regions, including our Milky Way 1 , 2 . Bars are supposed to develop in dynamically cold stellar disks at low redshift, as the strong gas turbulence typical of disk galaxies at high redshift suppresses or delays bar formation 3 , 4 . Moreover, simulations predict bars to be almost absent beyond z  = 1.5 in the progenitors of Milky Way-like galaxies 5 , 6 . Here we report observations of ceers-2112, a barred spiral galaxy at redshift z phot  ≈ 3, which was already mature when the Universe was only 2 Gyr old. The stellar mass ( M ★  = 3.9 × 10 9  M ⊙ ) and barred morphology mean that ceers-2112 can be considered a progenitor of the Milky Way 7 – 9 , in terms of both structure and mass-assembly history in the first 2 Gyr of the Universe, and was the closest in mass in the first 4 Gyr. We infer that baryons in galaxies could have already dominated over dark matter at z  ≈ 3, that high-redshift bars could form in approximately 400 Myr and that dynamically cold stellar disks could have been in place by redshift z  = 4–5 (more than 12 Gyrs ago) 10 , 11 . We report observations of ceers-2112 that show that this galaxy, at a redshift of 3, unexpectedly has a barred spiral structure.

During the first 500 million years of cosmic history, the first stars and galaxies formed, seeding the Universe with heavy elements and eventually reionizing the intergalactic medium 1 – 3 . Observations with the James Webb Space Telescope (JWST) have uncovered a surprisingly high abundance of candidates for early star-forming galaxies, with distances (redshifts, z ), estimated from multiband photometry, as large as z  ≈ 16, far beyond pre-JWST limits 4 – 9 . Although such photometric redshifts are generally robust, they can suffer from degeneracies and occasionally catastrophic errors. Spectroscopic measurements are required to validate these sources and to reliably quantify physical properties that can constrain galaxy formation models and cosmology 10 . Here we present JWST spectroscopy that confirms redshifts for two very luminous galaxies with z  > 11, and also demonstrates that another candidate with suggested z  ≈ 16 instead has z  = 4.9, with an unusual combination of nebular line emission and dust reddening that mimics the colours expected for much more distant objects. These results reinforce evidence for the early, rapid formation of remarkably luminous galaxies while also highlighting the necessity of spectroscopic verification. The large abundance of bright, early galaxies may indicate shortcomings in current galaxy formation models or deviations from physical properties (such as the stellar initial mass function) that are generally believed to hold at later times. JWST spectroscopy confirms redshifts for two very luminous galaxies with z  > 11, and also demonstrates that another candidate with suggested z  ≈ 16 instead has z  = 4.9.

VLA A-array snapshots were obtained of a complete sample of steep-spectrum radio sources from the Texas Radio Interferometer survey. Though similar in sensitivity to the FIRST Survey, our A-array snapshots have better resolution, and are complementary to FIRST. All initial A-array maps are made, and we are comparing them to FIRST.

[Shortened for arXiv] We conduct a systematic search for \\(\\log(M_\\ast/M_\\odot) \\geq 9.5\\) quiescent galaxies at \\(z > 3\\) in six extragalactic deep fields observed with NIRCam, with the goal of extracting their physical and statistical features in a uniform and self-consistent manner. We exploit the ASTRODEEP-JWST photometric catalogs to single out robust candidates, including sources quenched only a few tens of Myr before the observation. We apply a SED-fitting procedure which explores three functional forms of star formation history and the \\(\\chi^2\\) probabilities of the solutions, with additional checks to minimise the contamination from interlopers, tuning our selection criteria against available spectroscopic data from the DAWN archive and simulated catalogs. We select 633 candidates, which we rank by a reliability parameter based on the probabilities of the quiescent and alternative star-forming solutions, with 291 candidates tagged as \"gold\". According to the best-fit models, 79\\% of the massive (\\(\\log(M_\\ast/M_\\odot) \\geq 10.5\\)) quiescent galaxies at \\(3 < z < 5\\) stopped forming stars at least 150 Myr before the time of observation, while 89\\% of low-mass sources have been quenched for less than 150 Myr. The abundance of low-mass old quiescent systems does not increase significantly with time from \\(z = 5\\) to 3: low-mass objects seem to be experiencing a short episode of quenching followed by rejuvenation (``breathing''), consistent with a downsizing scenario of galaxy formation. We also find an abrupt drop in the density of massive quiescent candidates at \\(z > 5\\). We derive estimates for the number density of early passive galaxies up to \\(z = 10\\) and compare them against various models: tensions with data remain in the modeling of the observed bimodality of time passed since quenching as a function of mass.

One of JWST's most remarkable discoveries is a population of compact red galaxies known as Little Red Dots (LRDs). Their existence raises many questions about their nature, origin, and evolution. These galaxies show a steep decline in number density-nearly two orders of magnitude-from \\(z=6\\) to \\(z=3\\). In this study, we explore their potential evolution by identifying candidate descendants in CEERS, assuming a single evolutionary path: the development of a blue star-forming outskirt around the red compact core. Our color-magnitude selection identifies galaxies as red as LRDs at \\(z<4\\), surrounded by young, blue stellar outskirts. Morphological parameters were derived from single Sérsic profile fits; physical properties were obtained from SED fitting using a stellar-only model. These \"post-LRD\" candidates show LRD-like features with \\(M_\\ast \\sim 10^{10} \\ M_\\odot \\), central densities (\\( \\Sigma_\\ast \\sim 10^{11} \\ M_\\odot \\ \\text{kpc}^{-2}\\) ), compact sizes, and red rest-frame colors, but with an added extended component. Their number density at \\(z = 3 \\pm 0.5\\) ( \\( \\sim 10^{-4.15} \\, \\text{Mpc}^{-3} \\)) matches that of LRDs at \\(5 < z < 7\\) , supporting a possible evolutionary link. We observe a redshift-dependent increase in outskirts mass fraction and galaxy size-from \\(\\sim 250\\) pc at \\( z = 5 \\) to \\(\\sim 600\\) pc at \\( z = 3 \\)-suggesting global stellar growth. Meanwhile, the core remains red and compact, but the V-shaped SED fades as the outskirts grow. These findings support an evolutionary scenario in which LRDs gradually acquire an extended stellar component over cosmic time by cold accretion. This may explain the apparent decline in their observed number density at lower redshift.

During the last decade, studies about highly attenuated and massive red star-forming galaxies (RedSFGs) at \\(z 4\\) have suggested that they could constitute a crucial population for unraveling the mechanisms driving the transition from vigorous star formation to quiescence at high redshifts. Since such a transition seems to be linked to a morphological transformation, studying the morphological properties of these RedSFGs is essential to our understanding of galaxy evolution. To this end, we are using JWST/NIRCam images from the CEERS survey to assemble a mass-complete sample of 188 massive galaxies at \\(z=3-4\\), for which we perform resolved-SED fit. After classifying galaxies into typical blue SFGs (BlueSFGs), RedSFGs and quiescent galaxies (QGs), we compare the morphologies of each population in terms of stellar mass density, SFR density, sSFR, dust-attenuation and mass-weighted age. We find that RedSFGs and QGs present similar stellar surface density profiles and that RedSFGs manifest a dust attenuation concentration significantly higher than that of BlueSFGs at all masses. This indicates that to become quiescent, a BlueSFG must transit through a major compaction phase once it has become sufficiently massive. At the same time, we find RedSFGs and QGs to account for more than \\(50\\%\\) of galaxies with \\( log(M_/M_)> 10.4\\) at this redshift. This transition mass corresponds to the \"critical mass\" delineating the bimodality between BlueSFGs and QGs in the local Universe. We then conclude that there is a bimodality between extended BlueSFGs and compact, highly attenuated RedSFGs that have undergone a major gas compaction phase enabling the latter to build a massive bulb in situ. There is evidence that this early-stage separation is at the origin of the local bimodality between BlueSFGs and QGs, which we refer to as a \"primeval bimodality\".

Optical rest-frame spectroscopic diagnostics are usually employed to distinguish between star formation and AGN-powered emission. However, this method is biased against dusty sources, hampering a complete census of the AGN population across cosmic epochs. To mitigate this effect, it is crucial to observe at longer wavelengths in the rest-frame near-infrared (near-IR), which is less affected by dust attenuation and can thus provide a better description of the intrinsic properties of galaxies. AGN diagnostics in this regime have not been fully exploited so far, due to the scarcity of near-IR observations of both AGNs and star-forming galaxies, especially at redshifts higher than 0.5. Using Cloudy photoionization models, we identify new AGN - star formation diagnostics based on the ratio of bright near-infrared emission lines, namely [SIII] 9530 Angstrom, [CI] 9850 Angstrom, [PII] 1.188 \\(\\mu m\\), [FeII] \\(1.257 \\mu m\\), and [FeII] \\(1.64 \\mu m\\) to Paschen lines (either Pa\\(\\gamma\\) or Pa\\(\\beta\\)), providing simple, analytical classification criteria. We apply these diagnostics to a sample of 64 star-forming galaxies and AGNs at 0 < z < 1, and 65 sources at 1 < z < 3 recently observed with JWST-NIRSpec in CEERS. We find that the classification inferred from the near-infrared is broadly consistent with the optical one based on the BPT and the [SII]/H\\(\\alpha\\) ratio. However, in the near-infrared, we find \\(\\sim 60 \\%\\) more AGNs than in the optical (13 instead of 8), with 5 sources classified as 'hidden' AGNs, showing a larger AGN contribution at longer wavelengths, possibly due to the presence of optically thick dust. The diagnostics we present provide a promising tool to find and characterize AGNs from z=0 to z=3 with low and medium-resolution near-IR spectrographs in future surveys.

We present measurements of morphological parameters from fitting 53,885 galaxies detected to a magnitude limit of F356W\\(< 28.5\\) in the CEERS NIRCam imaging with galfit in six broadband filters: F115W, F150W, F200W, F277W, F356W, and F444W. We provide a public catalog of Sérsic index, effective semi-major axis, axis ratio, integrated magnitude, and position angle for these galaxies in each of the filters. Uncertainties in the measured parameters are estimated from simulated galaxies that have similar noise and background properties as the observed galaxies. We compare our measurements with those in the CANDELS/EGS field measured with HST/WFC3 and find that the sizes agree to within 0.09 dex and the Sérsic indices agree to within 0.13 dex. We further present the evolution in the size-mass relation, and find that the evolution to \\(z9\\) is consistent with previous results derived at lower redshift. Finally, we look at the color gradients of galaxies at \\(12.5\\)), the color gradients are nearly flat with no dependence on mass, indicating that the stellar populations are more uniform throughout. The structural measurements presented are accurate to \\(20\\%\\) or better for most galaxies with F356W \\(<27.0\\) mag and will enable further studies of galaxy morphology to \\(z10\\).

We investigate the morphology and resolved physical properties of a sample of 22 IR-selected DSFG at cosmic noon using the JWST/NIRCam images obtained in the EGS field for the CEERS survey. The resolution of the NIRCam images allowed to spatially resolve these galaxies up to 4.4um and identify their bulge even when extinguished by dust. The goal of this study is to obtain a better understanding of the formation and evolution of FIR-bright galaxies by spatially resolving their properties using JWST in order to look through the dust and bridge the gap between the compact FIR sources and the larger optical SFG. Based on RGB images from the NIRCam filters, we divided each galaxy into several uniformly colored regions, fitted their respective SEDs, and measured physical properties. After classifying each region as SF or quiescent, we assigned galaxies to three classes, depending on whether active SF is located in the core, in the disk or in both. We find (i) that galaxies at a higher z tend to have a fragmented disk with a low core mass fraction. They are at an early stage of bulge formation. When moving toward a lower z, the core mass fraction increases, and the bulge growth is associated with a stabilization of the disk: the NIRCam data clearly point toward bulge formation in preexisting disks. (ii) Lopsidedness is a common feature of DSFGs. It could have a major impact on their evolution; (iii) 23% of galaxies have a SF core embedded in a quiescent disk. They seem to be undergoing outside-in quenching, often facilitated by their strong lopsidedness inducing instabilities. (iv) We show that half of our galaxies with SF concentrated in their core are good SMG counterpart candidates, demonstrating that compact SMGs are usually surrounded by a larger, less obscured disk. (v) Finally, we found surprising evidence for clump-like substructures being quiescent or residing in quiescent regions.

We present the results of deep, ground based U-band imaging with the Large Binocular Telescope of the Cosmic Evolution Survey (COSMOS) field as part of the near-UV imaging program, UVCANDELS. We utilize a seeing sorted stacking method along with night-to-night relative transparency corrections to create optimal depth and optimal resolution mosaics in the U-band, which are capable of reaching point source magnitudes of AB 26.5 mag at 3 sigma. These ground based mosaics bridge the wavelength gap between the HST WFC3 F27W and ACS F435W images and are necessary to understand galaxy assembly in the last 9-10 Gyr. We use the depth of these mosaics to search for the presence of U-band intragroup light (IGrL) beyond the local Universe. Regardless of how groups are scaled and stacked, we do not detect any U-band IGrL to unprecedented U-band depths of 29.1-29.6 mag/arcsec2, which corresponds to an IGrL fraction of less than 1% of the total group light. This stringent upper limit suggests that IGrL does not contribute significantly to the Extragalactic Background Light at short wavelengths. Furthermore, the lack of UV IGrL observed in these stacks suggests that the atomic gas observed in the intragroup medium (IGrM) is likely not dense enough to trigger star formation on large scales. Future studies may detect IGrL by creating similar stacks at longer wavelengths or by pre-selecting groups which are older and/or more dynamically evolved similar to past IGrL observations of compact groups and loose groups with signs of gravitational interactions.