How To Light It Up: Simulating Ram-Pressure Stripped X-ray Bright Tails

TL;DR

This paper uses numerical simulations to identify high ICM pressure as key for producing X-ray bright tails in ram-pressure stripped galaxies, matching observations and constraining ICM mixing and heat conduction.

Contribution

It demonstrates that high ICM pressure is essential for X-ray bright tails and compares simulations with observations to constrain ICM properties.

Findings

High ICM pressure produces X-ray bright tails.

Simulations match observed X-ray and Halpha emissions.

Constraints on ICM mixing and heat conduction are derived.

Abstract

Some tails of ram-pressure stripped galaxies are detected in HI, some in Halpha, and some in X-ray (but never all three so far). We use numerical simulations to probe the conditions for the production of X-ray bright tails, demonstrating that the primary requirement is a high pressure intracluster medium (ICM). This is because the stripped tail is mostly in pressure equilibrium with the ICM, but mixing leaves it with densities and temperatures intermediate between the cold gas in the disk and the hot ICM. Given a high enough ICM pressure, this mixed gas lies in the X-ray bright region of the phase diagram. We compare the simulations to observations of the ram pressure stripped tail of ESO 137-001, showing excellent agreement in the total measured X-ray and Halpha emission and non-flaring morphology of the tail, and consistent HI measurements. Using these comparisons we constrain the level of mixing and efficiency of heat conduction in the intracluster medium (ICM)