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Arxiv: The UNCOVER Survey: First Release of Ultradeep JWST/NIRSpec PRISM spectra for ~700 galaxies from z~0.3-13 in Abell 2744 Published: 8/7/2024 8:24:12 PM Updated: 2/13/2025 5:45:05 PM

Paper abstract: We present the design and observations of low resolution JWST/NIRSpec PRISMspectroscopy from the Ultradeep NIRSpec and NIRCam ObserVations before theEpoch of Reionization (UNCOVER) Cycle 1 JWST Treasury program. Targets areselected using JWST/NIRCam photometry from UNCOVER and other programs, andcover a wide range of categories and redshifts to ensure the legacy value ofthe survey. These categories include the first galaxies at z\gtrsim10, faintgalaxies during the Epoch of Reionization (z~6-8), high redshift AGN(z\gtrsim6), Population III star candidates, distant quiescent and dustygalaxies (1<~{}z<~ 6), and filler galaxies samplingredshift--color--magnitude space from z~0.1-13. Seven NIRSpec MSA masks acrossthe extended Abell 2744 cluster were observed, along with NIRCam parallelimaging in 8 filters (F090W, F115W, F150W, F200W, F277W, F356W, F410M, F444W,F480M) over a total area of ~26 arcmin^2, overlapping existing HST coveragefrom programs including the Hubble Frontier Fields and BUFFALO. We successfullyobserved 553 objects down to m_{\mathrm{F444W}}~30\mathrm{AB}, and byleveraging mask overlaps, we reach total on-target exposure times ranging from2.4-16.7h. We demonstrate the success rate and distribution of confirmedredshifts, and also highlight the rich information revealed by these ultradeepspectra for a subset of our targets. An updated lens model of Abell 2744 isalso presented, including 14 additional spectroscopic redshifts and finding atotal cluster mass ofM_{\mathrm{SL}}=(2.1\pm0.3)\times10^{15}\,\mathrm{M}_{\odot}. We publiclyrelease reduced 1D and 2D spectra for all objects observed in Summer 2023 alongwith a spectroscopic redshift catalog and the updated lens model of the cluster(https://jwst-uncover.github.io/DR4.html).