Document Type


Publication Date

January 2017


Here we utilize recent measures of galaxy total dynamical mass and X-ray gas luminosities (LX,Gas) for a sample of 29 massive early-type galaxies from the SLUGGS survey to probe LX, Gas–mass scaling relations. In particular, we investigate scalings with stellar mass, dynamical mass within 5 effective radii (Re) and total virial mass. We also compare these relations with predictions from Λ cold dark matter simulations. We find a strong linear relationship between LX, Gas and galaxy dynamical mass within 5Re, which is consistent with the recent cosmological simulations of Choi et al. that incorporate mechanical heating from AGN. We conclude that the gas surrounding massive early-type galaxies was shock-heated as it fell into collapsing dark matter haloes so that LX, Gas is primarily driven by the depth of a galaxy's potential well. Heating by an AGN plays an important secondary role in determining LX, Gas.


This article was originally published in Monthly Notices of the Royal Astronomical Society Letters, volume 464, issue 1. ©: 2016 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
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