The Tully–Fisher and mass–size relations from halo abundance matching

Abstract

The Tully-Fisher relation (TFR) expresses the connection between rotating galaxies and the dark matter haloes they inhabit, and therefore contains a wealth of information about galaxy formation. We construct a general framework to investigate whether models based on halo abundance matching are able to reproduce the observed stellar mass TFR and mass-size relation (MSR), and use the data to constrain galaxy formation parameters. Our model tests a range of plausible scenarios, differing in the response of haloes to disc formation, the relative angular momentum of baryons and dark matter, the impact of selection effects, and the abundance matching parameters. We show that agreement with the observed TFR puts an upper limit on the scatter between galaxy and halo properties, requires weak or reversed halo contraction, and favours selection effects that preferentially eliminate fast-rotating galaxies. The MSR constrains the ratio of the disc to halo specific angular momentum to be approximately in the range 0.6−1.2. We identify and quantify two problems that models of this nature face. (1) They predict too large an intrinsic scatter for the MSR, and (2) they predict too strong an anticorrelation between the TFR and MSR residuals. We argue that resolving these problems requires introducing a correlation between stellar surface density and enclosed dark matter mass. Finally, we explore the expected difference between the TFRs of central and satellite galaxies, finding that in the favoured models this difference should be detectable in a sample of ∼ 700 galaxies.

NIHAO XII: galactic uniformity in a ΛCDM universe

“…However, Dutton et al (2007Dutton et al ( , 2011 showed that when models are constrained to reproduce the sizes of galaxies, they also overpredict the circular velocities if haloes contract in response to galaxy formation (Blumenthal et al 1986;Gnedin et al 2004). Such a conclusion has been verified by subsequent studies (e.g., Desmond & Wechsler 2015;Chan et al 2015).…”

The relationship between galaxy and dark matter halo size from z ∼ 3 to the present

“…However, both numerical hydrodynamic simulations (Faucher-Giguère et al 2011;Anglés-Alcázar et al 2016) and observations of galaxy gas content and consumption times at z ∼ 1-2 (Saintonge et al 2013;Genzel et al 2015) are inconsistent with gas accretion ceasing completely at z ∼ 1-2 in disk galaxies in Milky Way or smaller sized halos. Desmond & Wechsler (2015) investigated a model based on abundance matching and an angular momentum partition model similar to Eqn. 6, but allowing for expansion as well as contraction due to baryonic processes.…”

“…Both of these quantities are expected to have significant halo-to-halo scatter. Indeed, Desmond & Wechsler (2015) showed that a model based on abundance matching plus an angular momentum partition type model similar to Eqn 6 produces too large a scatter in galaxy size at fixed stellar mass. Second, it holds across populations that are almost entirely disk dominated to ones that are almost entirely composed of giant ellipticals.…”

On the galaxy–halo connection in the EAGLE simulation

“…Table 1. Comparison of statistics of the galaxy-halo connection in observations (P07), the EAGLE simulation, an abundance matching model with sizes chosen to match the stellar mass-size relation by construction ("SHAM"), and an analogous model with sizes set by angular momentum partition ("SHAM+MMW"; Desmond & Wechsler 2015). s MSR is the scatter in size of the stellar mass-size relation, ρ denotes Spearman rank correlation coefficient, and ∆ is defined in Eq.…”