Details

Autor(en) / Beteiligte

• Setton, David J.
• Dey, Biprateep
• Khullar, Gourav
• Bezanson, Rachel
• Newman, Jeffrey A.
• Aguilar, Jessica N.
• Ahlen, Steven
• Andrews, Brett H.
• Brooks, David
• de la Macorra, Axel
• Dey, Arjun
• Eftekharzadeh, Sarah
• Font-Ribera, Andreu
• A Gontcho, Satya Gontcho
• Kremin, Anthony
• Juneau, Stephanie
• Landriau, Martin
• Meisner, Aaron
• Miquel, Ramon
• Moustakas, John
• Pearl, Alan
• Prada, Francisco
• Tarlé, Gregory
• Siudek, Małgorzata
• Weaver, Benjamin Alan
• Zhou, Zhimin
• Zou, Hu

Titel

DESI Survey Validation Spectra Reveal an Increasing Fraction of Recently Quenched Galaxies at z ∼ 1

Ist Teil von

• Astrophysical journal. Letters, 2023-04, Vol.947 (2), p.L31

Ort / Verlag

Austin: The American Astronomical Society

Erscheinungsjahr

2023

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Abstract 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 < z < 1.3. We use Prospector to infer nonparametric star formation histories and identify a significant population of recently quenched galaxies that have joined the quiescent population within the past ∼1 Gyr. The highest-redshift subset (277 at z > 1) of our sample of recently quenched galaxies represents the largest spectroscopic sample of post-starburst galaxies at that epoch. At 0.4 < z < 0.8, we measure the number density of quiescent LRGs, finding that recently quenched galaxies constitute a growing fraction of the massive galaxy population with increasing look-back time. Finally, we quantify the importance of this population among massive ( log ( M ⋆ / M ⊙ ) > 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.