Dark X-Ray Galaxies in the A1367 Galaxy Cluster

Date

2021-08-24

Department

Program

Citation of Original Publication

Henriksen, Mark; Dusek, Scott; Dark X-Ray Galaxies in the A1367 Galaxy Cluster; The Astrophysical Journal Letters, Volume 917, Number 2, 24 August, 2021; https://doi.org/10.3847/2041-8213/abf941

Rights

This item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author.
Access to this item will begin on 2022-08-24

Subjects

Abstract

We have characterized a sample of extended X-ray sources in the A1367 galaxy cluster that lack optical counterparts. The sources are galaxy size and have an average total mass of 1.3 × 10¹¹ solar masses. The average hot gas mass is 3.0 × 10⁹ solar masses and the average X-ray luminosity is 4.3 × 10⁴¹ erg cm⁻² s⁻¹. Analysis of a composite source spectrum indicates the X-ray emission is thermal, with temperature of 1.25–1.45 keV and has low metallicity, 0.026–0.067 solar. The average hot gas radius (12.7 kpc) is well matched to nominal stripping radius. We argue that this optically dark, X-ray bright galaxy population forms by a sequence of stripping followed by heating and mixing with the intracluster medium.