DESI Survey Validation Spectra Reveal an Increasing Fraction of Recently Quenched Galaxies at z ∼ 1
DESI Survey Validation Spectra Reveal an Increasing Fraction of Recently Quenched Galaxies at z ∼ 1
复制标题
DOI：
10.3847/2041-8213/acc9b5
复制
发表时间：
2022-12
期刊：
影响因子：
--
通讯作者：
David J. Setton;B. Dey;G. Khullar;R. Bezanson;J. Newman;J. Aguilar;S. Ahlen;B. Andrews;D. Brooks;A. de la Macorra;A. Dey;S. Eftekharzadeh;A. Font-Ribera;S. G. A Gontcho;A. Kremin;S. Juneau;M. Landriau;A. Meisner;R. Miquel;J. Moustakas;Alan N. Pearl;F. Prada;G. Tarlé;M. Siudek;B. Weaver;Zhi-min Zhou;H. Zou
中科院分区：
文献类型：
--
作者：
David J. Setton;B. Dey;G. Khullar;R. Bezanson;J. Newman;J. Aguilar;S. Ahlen;B. Andrews;D. Brooks;A. de la Macorra;A. Dey;S. Eftekharzadeh;A. Font-Ribera;S. G. A Gontcho;A. Kremin;S. Juneau;M. Landriau;A. Meisner;R. Miquel;J. Moustakas;Alan N. Pearl;F. Prada;G. Tarlé;M. Siudek;B. Weaver;Zhi-min Zhou;H. Zou
我们利用来自新型暗能量光谱仪器调查验证光谱样本的约17,000个明亮的红色星系（LRGs），利用其深度（约2.5小时星系−1曝光时间）光谱来表征最近淬灭的星系对大质量星系群的贡献，我们的最近淬灭星系样本代表了该时代星暴后星系的最大光谱样本。在0.4 11.2)LRGs，通过测量每个星系在观测前千禧年形成的恒星质量的比例，f 1gyr。虽然在z ~ 0.4（占总星系数的0.5%）处具有f - 1gyr > 0.1的星系很少见，但在z ~ 0.8处，它们构成了大质量星系的3%。放宽这一阈值，我们发现在z ~ 0.8处，f - 1gyr >.5 %的星系构成了大质量星系群的~ 10%。我们还发现了一个小而重要的星系样本，它们在z = 1.1-1.3处形成时的Gyr为50%，这意味着它们可能类似于在相似的时间尺度上形成的高红移静止星系。未来对这个前所未有的样本的分析有望阐明导致大质量星系在宇宙正午之后熄灭的物理机制。
We utilize ∼17,000 bright luminous red galaxies (LRGs) from the novel Dark Energy Spectroscopic Instrument Survey Validation spectroscopic sample, leveraging its deep (∼2.5 hr galaxy−1 exposure time) spectra to characterize the contribution of recently quenched galaxies to the massive galaxy population at 0.4 1) of our sample of recently quenched galaxies represents the largest spectroscopic sample of post-starburst galaxies at that epoch. At 0.4 11.2) LRGs by measuring the fraction of stellar mass each galaxy formed in the gigayear before observation, f 1 Gyr. Although galaxies with f 1 Gyr > 0.1 are rare at z ∼ 0.4 (≲0.5% of the population), by z ∼ 0.8, they constitute ∼3% of massive galaxies. Relaxing this threshold, we find that galaxies with f 1 Gyr > 5% constitute ∼10% of the massive galaxy population at z ∼ 0.8. We also identify a small but significant sample of galaxies at z = 1.1–1.3 that formed with f 1 Gyr > 50%, implying that they may be analogs to high-redshift quiescent galaxies that formed on similar timescales. Future analysis of this unprecedented sample promises to illuminate the physical mechanisms that drive the quenching of massive galaxies after cosmic noon.