The Typical Massive Quiescent Galaxy at z ∼ 3 is a Post-starburst

D’Eugenio, C.; Daddi, E.; Gobat, R.; Strazzullo, V.; Lustig, P.; Delvecchio, I.; Jin, S.; Puglisi, A.; Calabró, A.; Mancini, C.; Dickinson, M.; Cimatti, A.; Onodera, M.

doi:10.3847/2041-8213/ab7a96

The Typical Massive Quiescent Galaxy at z ∼ 3 is a Post-starburst

D’Eugenio, C.; Daddi, E.; Gobat, R.; Strazzullo, V.; Lustig, P.; Delvecchio, I.; Jin, S.; Puglisi, A.; Calabró, A.; Mancini, C.; Dickinson, M.; Cimatti, A.; Onodera, M.

Authors

C. D’Eugenio

E. Daddi

R. Gobat

V. Strazzullo

P. Lustig

I. Delvecchio

S. Jin

Dr Annagrazia Puglisi annagrazia.puglisi@durham.ac.uk
Academic Visitor

A. Calabró

C. Mancini

M. Dickinson

A. Cimatti

M. Onodera

Abstract

We have obtained spectroscopic confirmation with Hubble Space Telescope WFC3/G141 of a first sizeable sample of nine quiescent galaxies at 2.4 < z < 3.3. Their average near-UV/optical rest-frame spectrum is characterized by low attenuation (AV ~ 0.6 mag) and a strong Balmer break, larger than the 4000 Å break, corresponding to a fairly young age of ~300 Myr. This formally classifies a substantial fraction of classically selected quiescent galaxies at z ~ 3 as post-starbursts, marking their convergence to the quenching epoch. The rapid spectral evolution with respect to z ~ 1.5 quiescent galaxies is not matched by an increase of residual star formation, as judged from the weak detection of [O ii]λ3727 emission, pointing to a flattening of the steep increase in gas fractions previously seen from z ~ 0 to 1.8. However, radio 3 GHz stacked emission implies either much stronger dust-obscured star formation or substantial further evolution in radio-mode AGN activity with respect to z ~ 1.5.

Citation

D’Eugenio, C., Daddi, E., Gobat, R., Strazzullo, V., Lustig, P., Delvecchio, I., …Onodera, M. (2020). The Typical Massive Quiescent Galaxy at z ∼ 3 is a Post-starburst. Astrophysical Journal Letters, 892(1), Article L2. https://doi.org/10.3847/2041-8213/ab7a96

Journal Article Type	Article
Acceptance Date	Feb 27, 2020
Online Publication Date	Mar 20, 2020
Publication Date	Mar 20, 2020
Deposit Date	Apr 17, 2020
Publicly Available Date	Apr 17, 2020
Journal	Astrophysical Journal
Print ISSN	2041-8205
Publisher	American Astronomical Society
Peer Reviewed	Peer Reviewed
Volume	892
Issue	1
Article Number	L2
DOI	https://doi.org/10.3847/2041-8213/ab7a96