A break in the high-redshift stellar mass Tully–Fisher relation

Abstract

We investigate the stellar-mass Tully-Fisher relation (TFR) between the stellar mass and the integrated gas velocity dispersion, quantified by the kinematic estimator S 0.5 measured from strong emission lines in spectra of galaxies at 0 < z < 5. We combine luminosity-selected galaxies ('high-luminosity sample') with galaxies selected in other ways ('low-luminosity sample') to cover a range in stellar mass that spans almost five orders of magnitude: 7.0 ∼ < log M * /M ⊙ ∼ < 11.5. We find that the logarithmic power-law slope and normalisation of the TFR are independent of redshift out to z ∼ 3. The scatter in the TFR is < 0.5 dex such that the gas velocity dispersion can be used as a proxy for the stellar mass of a galaxy independently of its redshift. At z > 3 the scatter increases and the existence of a correlation is not obvious. The high-luminosity sample exhibits a flatter slope of 1.5±0.2 at z < 3 compared to the lowluminosity sample slope of 2.9±0.3, suggesting a turnover in the TFR. The combined sample is well fit with a break in the TFR at a characteristic stellar mass scale of M * ∼ 10 10 M ⊙ , with no significant evolution out to z ∼ 3. We demonstrate that a break in the TFR with a steeper slope at the low-mass end is a natural consequence of galaxy models with a mass-dependent stellar to halo-mass ratio.

The KMOS Lens-Amplified Spectroscopic Survey (KLASS): Kinematics and clumpiness of low-mass galaxies at cosmic noon

“…These data do not suggest that the slope has any dependence on the stellar mass and redshift when using the circular velocity, which is in good agreement with the results from Harrison et al (2017), for example, but in contradiction with Christensen & Hjorth (2017), where they reported a steeper slope for low-mass galaxies. However, this sample is small and more statistics are needed to better look at the variation of the slope with redshift and stellar mass.…”

“…Simons et al (2015) found that the galaxies with log(M /M ) < 9.5 do not follow the Tully-Fisher relation since they show a large scatter at 0.1 < z < 0.375. In addition, Christensen & Hjorth (2017) reported a power-law slope and normalisation independent of the redshift, but also found a break with a steeper slope for low-mass galaxies in their sample at 0 < z < 3 with stellar mass of 7.0<log(M /M )<11.5. In this section, we use KLASS to investigate the redshift and stellar mass evolution of the Tully-Fisher relation to extend these previous studies to low-mass galaxies at 0.6 < z < 2.3.…”

Mass and metallicity scaling relations of high-redshift star-forming galaxies selected by GRBs

“…1. We clearly see a correlation between stellar mass and σHα (see also Christensen & Hjorth 2017). The velocity width of the Hα emission line contains contributions from rotational velocity.…”

Exploring galaxy dark matter haloes across redshifts with strong quasar absorbers

“…Several effects could contribute to the observed scatter of the data points relative to that predicted by the various DM halo models. Outflows from galaxies would increase both ∆v90 and σem as the latter also scales with galaxy star-formation rates (Krühler et al 2015;Christensen & Hjorth 2017). Outflows will therefore cause minor increase in the scatter of the ∆v90/σem ratio.…”