A transition mass in the local Tully-Fisher relation
Abstract
We study the stellar mass Tully-Fisher relation (TFR; stellar mass versus rotation velocity) for a morphologically blind selection of emission line galaxies in the field at redshifts 0.1 < z < 0.375. Kinematics (σg, Vrot) are measured from emission lines in Keck/DEIMOS spectra and quantitative morphology is measured from V- and I-band Hubble images. We find a transition stellar mass in the TFR, log M*/M⊙ = 9.5. Above this mass, nearly all galaxies are rotation dominated, on average more morphologically disc-like according to quantitative morphology, and lie on a relatively tight TFR. Below this mass, the TFR has significant scatter to low rotation velocity and galaxies can either be rotation-dominated discs on the TFR or asymmetric or compact galaxies which scatter off. We refer to this transition mass as the `mass of disc formation', Mdf because above it all star-forming galaxies form discs (except for a small number of major mergers and highly star-forming systems), whereas below it a galaxy may or may not form a disc.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- September 2015
- DOI:
- 10.1093/mnras/stv1298
- arXiv:
- arXiv:1506.04144
- Bibcode:
- 2015MNRAS.452..986S
- Keywords:
-
- galaxies: evolution;
- galaxies: formation;
- galaxies: fundamental parameters;
- galaxies: kinematics and dynamics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- Accepted to MNRAS. 14 pages, 7 figures