The gas mass reservoir of quiescent galaxies at cosmic noon
Abstract
We present a 1.1 mm stacking analysis of moderately massive (log(M*/M⊙) = 10.7 ± 0.2) quiescent galaxies (QGs) at ⟨z⟩∼1.5, searching for cold dust continuum emission, which serves as an excellent tracer of dust and gas mass. Using both the recent GOODS-ALMA survey, as well as the full suite of ALMA Band-6 ancillary data in the GOODS-S field, we report the tentative detection of a dust continuum equivalent of the dust mass log(Mdust/M⊙) = 7.47 ± 0.13 and gas mass log(Mgas/M⊙) = 9.42 ± 0.14. The emerging gas fraction is fgas = 5.3 ± 1.8%, consistent with the results of previous stacking analyses based on lower resolution sub(mm) observations. Our results support the scenario where high-z QGs exhibit a larger fgas value by one order of magnitude compared to their local counterparts and have experienced quenching with a non-negligible gas reservoir in their interstellar medium, namely, with gas retention. Our subsequent analysis yields an anti-correlation between the fgas and the stellar mass of QGs, especially in the high-mass end where galaxies reside in the most massive halos. The fgas − M* anti-correlation promotes the selection bias as a possible solution to the tension between the stacking results pointing towards gas retention in high-z QGs of moderate M* and studies of individual targets that favour a fully depleted ISM in massive (log(M*/M⊙) > 11.2) high-z QGs.
- Publication:
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Astronomy and Astrophysics
- Pub Date:
- June 2023
- DOI:
- 10.1051/0004-6361/202345977
- arXiv:
- arXiv:2303.12110
- Bibcode:
- 2023A&A...674A.166B
- Keywords:
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- Galaxy: evolution;
- galaxies: ISM;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- Accepted to A&