English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We analyse Chandra X-ray Observatory observations of a set of galaxy clustersselected by the South Pole Telescope using a new publicly-availableforward-modelling projection code, MBProj2, assuming hydrostatic equilibrium.By fitting a powerlaw plus constant entropy model we find no evidence for acentral entropy floor in the lowest-entropy systems. A model of the underlyingcentral entropy distribution shows a narrow peak close to zero entropy whichaccounts for 60 per cent of the systems, and a second broader peak around 130keV cm^2. We look for evolution over the 0.28 to 1.2 redshift range of thesample in density, pressure, entropy and cooling time at 0.015 R_500 and at 10kpc radius. By modelling the evolution of the central quantities with a simplemodel, we find no evidence for a non-zero slope with redshift. In addition, anon-parametric sliding median shows no significant change. The fraction ofcool-core clusters with central cooling times below 2 Gyr is consistent aboveand below z=0.6 (~30-40 per cent). Both by comparing the median thermodynamicprofiles, centrally biased towards cool cores, in two redshift bins, and bymodelling the evolution of the unbiased average profile as a function ofredshift, we find no significant evolution beyond self-similar scaling in anyof our examined quantities. Our average modelled radial density, entropy andcooling-time profiles appear as powerlaws with breaks around 0.2 R_500. Thedispersion in these quantities rises inwards of this radius to around 0.4 dex,although some of this scatter can be fit by a bimodal model.

Hydrostatic Chandra X-ray analysis of SPT-selected galaxy clusters - I. Evolution of profiles and core properties