The surprising lack of effect from stellar feedback on the gas stripping rate from massive jellyfish galaxies

Abstract

ABSTRACT We study the role of star formation and stellar feedback in a galaxy being ram pressure (RP) stripped on its infall into a cluster. We use hydrodynamical wind-tunnel simulations of a massive galaxy (Mstar = 1011 M⊙) moving into a massive cluster (Mcluster = 1015 M⊙). We have two types of simulations: with and without star formation and stellar feedback, SF, and radiative cooling (RC), respectively. For each type, we simulate four realizations of the same galaxy: a face-on wind, edge-on wind, 45° angled wind, and a control galaxy not subject to RP. We directly compare the stripping evolution of galaxies with and without star formation. We find that stellar feedback has no direct effect on the stripping process, i.e. there is no enhancement in stripping via a velocity kick to the interstellar medium (ISM) gas. The main difference between RC and SF galaxies is due to the indirect effect of stellar feedback, which produces a smoother and more homogeneous ISM. Hence, while the average gas surface density is comparable in both simulation types, the scatter is broader in the RC galaxies. As a result, at the galaxy outskirts overdense clumps survive in RC simulation, and the stripping proceeds more slowly. At the same time, in the inner disc, underdense gas in the RC holes is removed faster than the smoothly distributed gas in the SF simulation. For our massive galaxy, we therefore find that the effect of feedback on the stripping rate is almost negligible, independent of wind angle.