# The Journey Counts: The Importance of Including Orbits when Simulating Ram Pressure Stripping

## TL;DR

This study shows that including variable ram pressure profiles in galaxy simulations significantly affects the morphology, velocity structure, and stripping rates of gas disks, emphasizing the need for realistic modeling of galaxy infall into clusters.

## Contribution

It demonstrates that using a varying ram pressure profile, rather than a constant one, results in more accurate simulations of galaxy gas stripping and morphology during cluster infall.

## Key findings

- Varying ram pressure leads to different tail structures and velocities.
- Constant wind simulations cannot accurately model galaxy infall.
- Varying wind results in lower stripping rates with radiative cooling.

## Abstract

We investigate the importance of varying the ram pressure to more realistically mimic the infall of a cluster satellite galaxy when comparing ram pressure stripping simulations to observations. We examine the gas disk and tail properties of stripped cluster galaxies in eight "wind-tunnel" hydrodynamical simulations with either varying or constant ram pressure strength. In simulations without radiative cooling, applying a varying wind leads to significantly different density and velocity structure in the tail than found when applying a constant wind, although the stripping rate, disk mass, and disk radius remain consistent in both scenarios. In simulations with radiative cooling, the differences between a constant and varying wind are even more pronounced. Not only is there a difference in morphology and velocity structure in the tails, but a varying wind leads to a much lower stripping rate, even after the varying wind has reached the ram pressure strength of the constant wind. Also, galaxies in constant and varying wind simulations with the same gas disk mass do not have in the same gas disk radius. A constant wind cannot appropriately model the ram pressure stripping of a galaxy entering a cluster. We conclude that simulations attempting detailed comparisons with observations must take the variation of the ram pressure profile due to a galaxy's orbit into consideration.