The angular momentum of disc galaxies at z = 1
Abstract
We investigate the relation between stellar mass (M⋆) and specific stellar angular momentum (j⋆), or "Fall relation", for a sample of 17 isolated, regularly rotating disc galaxies at z ∼ 1. All galaxies have rotation curves determined from Hα emission-line data; HST imaging in optical and infrared filters; and robust determinations of their stellar masses. We use HST images in f814w and f160w filters, roughly corresponding to rest-frames B and I bands, to extract surface-brightness profiles for our systems. We robustly bracket j⋆ by assuming that rotation curves beyond the outermost Hα rotation point stay either flat or follow a Keplerian fall-off. By comparing our measurements with those determined for disc galaxies in the local universe, we find no evolution in the Fall relation in the redshift range 0 < z < 1, regardless of the band used and despite the uncertainties in the stellar rotation curves at large radii. This result holds unless stellar masses at z = 1 are systematically underestimated by ≳50%. Our findings are compatible with expectations based on a ΛCDM cosmological framework and support a scenario where both the stellar Tully-Fisher and mass-size relations for spirals do not evolve significantly in this redshift range.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- January 2019
- DOI:
- 10.1051/0004-6361/201834456
- arXiv:
- arXiv:1812.08479
- Bibcode:
- 2019A&A...621L...6M
- Keywords:
-
- galaxies: kinematics and dynamics;
- galaxies: evolution;
- galaxies: high-redshift;
- galaxies: photometry;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 11 pages, 4 figures, 1 table. Accepted by A&