Ram pressure profiles in galaxy groups and clusters

TL;DR

This paper models ram pressure profiles in galaxy groups and clusters across various redshifts using simulations and semi-analytic methods, providing fitting formulas for easier integration into galaxy evolution models.

Contribution

It introduces a self-consistent method to determine ram pressure profiles and provides simple parameter-dependent beta profile models for different halo masses and redshifts.

Findings

Ram pressure profiles follow beta models with parameters depending on mass and redshift.

Fitting formulae enable incorporation of ram pressure effects into semi-analytic galaxy formation models.

Profiles are validated across a wide range of halo masses and redshifts.

Abstract

Using a hybrid method which combines non-radiative hydrodynamical simulations with a semi-analytic model of galaxy formation, we determine the ram pressure as a function of halocentric distance experienced by galaxies in haloes with virial masses 12.5 <= log (M_200 h/M_Sun) < 15.35, for redshifts 0 <= z <= 3. The ram pressure is calculated with a self-consistent method which uses the simulation gas particles to obtain the properties of the intergalactic medium. The ram pressure profiles obtained can be well described by beta profile models, with parameters that depend on redshift and halo virial mass in a simple fashion. The fitting formulae provided here will prove useful to include ram pressure effects into semi-analytic models based on methods which lack gas physics, such as dark matter-only simulations or the Press-Schechter formalism.