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  • COSMOS Spectroscopic Redshift Compilation (First Data Release): 488,000 Redshifts Encompassing Two Decades of Spectroscopy
Title: COSMOS Spectroscopic Redshift Compilation (First Data Release): 488,000 Redshifts Encompassing Two Decades of Spectroscopy
Abstract We present the COSMOS Spectroscopic Redshift Compilation encompassing ∼20 yr of spectroscopic redshifts within a 10 deg2area centered on the 2 deg2COSMOS legacy field. This compilation contains 487,666 redshifts of 266,284 unique objects from 138 individual programs up toz ∼ 8 with median stellar mass ∼108.4–1010M⊙(redshift dependent). Rest-frameNUVrJcolors and star formation rate–stellar mass correlations show that the compilation primarily contains low-to-intermediate-mass star-forming and massive, quiescent galaxies atz < 1.25 and mostly low-mass bursty star-forming galaxies atz > 2. Sources in the compilation cover a diverse range of environments, including protoclusters such as “Hyperion.” The full compilation is 50% spectroscopically complete byi ∼ 23.4 mag andKs ∼ 21.6 mag; however, this is redshift dependent. Spatially, the compilation is >50% (>30%) complete within the central (outer) region limited toi < 24 mag andKs < 22.5 mag, separately. We demonstrate how the compilation can be used to validate photometric redshifts and investigate calibration metrics. By training self-organizing maps on COSMOS2020/Classic and projecting the compilation onto it, we find key subpopulations currently lacking spectroscopic coverage, includingz < 1 intermediate-mass quiescent and low-/intermediate-mass bursty star-forming galaxies,z ∼ 2 massive quiescent galaxies, andz > 3 massive star-forming galaxies. This highlights how combining self-organizing maps with our compilation can provide guidance for future spectroscopic observations to get a complete spectroscopic view of galaxy populations. Lastly, the compilation will undergo periodic data releases incorporating new spectroscopic redshifts and providing a lasting legacy resource for the community.  more » « less
Award ID(s):
2009572
PAR ID:
10682504
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
Astrophysical Journal Supplement
Date Published:
Journal Name:
The Astrophysical Journal Supplement Series
Volume:
282
Issue:
1
ISSN:
0067-0049
Page Range / eLocation ID:
6
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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