Mass Distribution in Galaxy Cluster Cores

Abstract

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The Onset of Thermally Unstable Cooling from the Hot Atmospheres of Giant Galaxies in Clusters: Constraints on Feedback Models

“…Hogan et al (2017) developed techniques to determine cluster mass profiles across wide radial ranges that extend from cluster halos into the cores of the central galaxies. We adopt this methodology in this paper to calculate more accurate t cool /t ff profiles for a large sample of clusters, many of which are actively experiencing thermally unstable cooling.…”

“…Furthermore the t cool /t ff minimum is usually reported to occur at cluster-centric radii of 5-20kpc (e.g., Gaspari et al 2012;Hogan et al 2017). Highresolution measurements are therefore required to constrain the minimum value of t cool /t ff .…”

“…Angular scale is plotted rather than redshift to allow a more direct view of resolvable scales. It was found in Hogan et al (2017) that taking a minimum circular annulus of radius 3×0.492 arcsec pixels (roughly equivalent to the Chandra resolution), and then extending the radius of each successive annulus by one pixel (i.e., widths of 3, 4, 5, etc. pixels) provided good spatial sampling while ensuring more successful deprojection.…”

“…Data reduction was performed using CIAO version 4.7 with CALDB version 4.6.7 (Fruscione et al 2006) following the methods described in Hogan et al (2017). A brief outline is given here.…”

Buoyant AGN Bubbles in the Quasi-isothermal Potential of NGC 1399

“…This deviation may indicate a transition from the potential of the BCG to that of the Fornax Cluster. Hogan et al (2017) also found § For an annular sector, we calculate its volume as V = . For a box region, we assume it is a cylinder in 3D with an approximately radial symmetry axis and we calculate its volume as V = l × π(w/2) 2 .…”