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Aims.JWST/NIRCam provides rest-frame near-IR photometry of galaxies up toz = 2.5 with exquisite depth and accuracy. This affords us an unprecedented view of the evolution of the UV/optical/near-IR color distribution and its interpretation in terms of the evolving dust attenuation,A_V. Methods.We used the value-added data products (photometric redshift, stellar mass, rest-frameU − VandV − Jcolors, andA_V) provided by the public DAWN JWST Archive. These data products derive from fitting the spectral energy distributions obtained from multiple NIRCam imaging surveys, augmented with preexisting HST imaging data. Our sample consists of a stellar-mass-complete sample of ≈28 000M_⋆ >  10⁹ M_⊙galaxies in the redshift range 0.5 <  z <  2.5. Results.TheV − Jcolor distribution of star-forming galaxies evolves strongly, in particular for high-mass galaxies (M_⋆ >  3 × 10¹⁰ M_⊙), which have a pronounced tail of very red galaxies reachingV − J >  2.5 atz >  1.5 that does not exist atz <  1. Such redV − Jcan only be explained by dust attenuation, with typical values forM_⋆ ≈ 10¹¹ M_⊙galaxies in the rangeA_V ≈ 1.5 − 3.5 atz ≈ 2. This redshift evolution went largely unnoticed before. Today, however, photometric redshift estimates for the reddest (V − J >  2.5), most attenuated galaxies have markedly improved thanks to the new, precise photometry, which is in much better agreement with the 25 available spectroscopic redshifts for such galaxies. The reddest population readily stands out as the independently identified population of galaxies detected at submillimeter wavelengths. Despite the increased attenuation,U − Vcolors across the entire mass range are slightly bluer at higherz. A well-defined and tight color sequence exists at redshifts 0.5 <  z <  2.5 forM_⋆ >  3 × 10¹⁰ M_⊙quiescent galaxies, in bothU − VandV − J, but inV − Jit is bluer rather than redder compared to star-forming galaxies. In conclusion, whereas the rest-frame UV-optical color distribution evolves remarkably little fromz = 0.5 toz = 2.5, the rest-frame optical/near-IR color distribution evolves strongly, primarily due to a very substantial increase with redshift in dust attenuation for massive galaxies. 

Abstract While space-borne optical and near-infrared facilities have succeeded in delivering a precise and spatially resolved picture of our Universe, their small survey area is known to underrepresent the true diversity of galaxy populations. Ground-based surveys have reached comparable depths but at lower spatial resolution, resulting in source confusion that hampers accurate photometry extractions. What once was limited to the infrared regime has now begun to challenge ground-based ultradeep surveys, affecting detection and photometry alike. Failing to address these challenges will mean forfeiting a representative view into the distant Universe. We introduceThe Farmer: an automated, reproducible profile-fitting photometry package that pairs a library of smooth parametric models fromThe Tractorwith a decision tree that determines the best-fit model in concert with neighboring sources. Photometry is measured by fitting the models on other bands leaving brightness free to vary. The resulting photometric measurements are naturally total, and no aperture corrections are required. Supporting diagnostics (e.g.,χ²) enable measurement validation. As fitting models is relatively time intensive,The Farmeris built with high-performance computing routines. We benchmarkThe Farmeron a set of realistic COSMOS-like images and find accurate photometry, number counts, and galaxy shapes.The Farmeris already being utilized to produce catalogs for several large-area deep extragalactic surveys where it has been shown to tackle some of the most challenging optical and near-infrared data available, with the promise of extending to other ultradeep surveys expected in the near future.The Farmeris available to download from GitHub (https://github.com/astroweaver/the_farmer) and Zenodo (https://doi.org/10.5281/zenodo.8205817). 

ABSTRACT We present a catalogue of 22 755 objects with slitless, optical, Hubble Space Telescope (HST) spectroscopy from the Grism Lens-Amplified Survey from Space (GLASS). The data cover ∼220 sq. arcmin to 7-orbit (∼10 ks) depth in 20 parallel pointings of the Advanced Camera for Survey’s G800L grism. The fields are located 6 arcmin away from 10 massive galaxy clusters in the HFF and CLASH footprints. 13 of the fields have ancillary HST imaging from these or other programs to facilitate a large number of applications, from studying metal distributions at z ∼ 0.5, to quasars at z ∼ 4, to the star formation histories of hundreds of galaxies in between. The spectroscopic catalogue has a median redshift of 〈z〉 = 0.60 with a median uncertainty of $$\Delta z / (1+z)\lesssim 2{{\ \rm per\ cent}}$$ at $$F814\mathit{ W}\lesssim 23$$ AB. Robust continuum detections reach a magnitude fainter. The 5 σ limiting line flux is $$f_{\rm lim}\approx 5\times 10^{-17}\rm ~erg~s^{-1}~cm^{-2}$$ and half of all sources have 50 per cent of pixels contaminated at ≲1 per cent. All sources have 1D and 2D spectra, line fluxes/uncertainties and identifications, redshift probability distributions, spectral models, and derived narrow-band emission-line maps from the Grism Redshift and Line Analysis tool (grizli). We provide other basic sample characterizations, show data examples, and describe sources and potential investigations of interest. All data and products will be available online along with software to facilitate their use. 

ABSTRACT The magnifications of compact-source lenses are extremely sensitive to the presence of low-mass dark matter haloes along the entire sightline from the source to the observer. Traditionally, the study of dark matter structure in compact-source strong gravitational lenses has been limited to radio-loud systems, as the radio emission is extended and thus unaffected by microlensing which can mimic the signal of dark matter structure. An alternate approach is to measure quasar nuclear-narrow-line emission, which is free from microlensing and present in virtually all quasar lenses. In this paper, we double the number of systems which can be used for gravitational lensing analyses by presenting measurements of narrow-line emission from a sample of eight quadruply imaged quasar lens systems, WGD J0405−3308, HS 0810+2554, RX J0911+0551, SDSS J1330+1810, PS J1606−2333, WFI 2026−4536, WFI 2033−4723, and WGD J2038−4008. We describe our updated grism spectral modelling pipeline, which we use to measure narrow-line fluxes with uncertainties of 2–10 per cent, presented here. We fit the lensed image positions with smooth mass models and demonstrate that these models fail to produce the observed distribution of image fluxes over the entire sample of lenses. Furthermore, typical deviations are larger than those expected from macromodel uncertainties. This discrepancy indicates the presence of perturbations caused by small-scale dark matter structure. The interpretation of this result in terms of dark matter models is presented in a companion paper. 

Abstract The Cosmic Evolution Survey (COSMOS) has become a cornerstone of extragalactic astronomy. Since the last public catalog in 2015, a wealth of new imaging and spectroscopic data have been collected in the COSMOS field. This paper describes the collection, processing, and analysis of these new imaging data to produce a new reference photometric redshift catalog. Source detection and multiwavelength photometry are performed for 1.7 million sources across the 2 deg 2 of the COSMOS field, ∼966,000 of which are measured with all available broadband data using both traditional aperture photometric methods and a new profile-fitting photometric extraction tool, The Farmer , which we have developed. A detailed comparison of the two resulting photometric catalogs is presented. Photometric redshifts are computed for all sources in each catalog utilizing two independent photometric redshift codes. Finally, a comparison is made between the performance of the photometric methodologies and of the redshift codes to demonstrate an exceptional degree of self-consistency in the resulting photometric redshifts. The i < 21 sources have subpercent photometric redshift accuracy and even the faintest sources at 25 < i < 27 reach a precision of 5%. Finally, these results are discussed in the context of previous, current, and future surveys in the COSMOS field. Compared to COSMOS2015, it reaches the same photometric redshift precision at almost one magnitude deeper. Both photometric catalogs and their photometric redshift solutions and physical parameters will be made available through the usual astronomical archive systems (ESO Phase 3, IPAC-IRSA, and CDS).