Description
This table, the Archive of Chandra Cluster Entropy Profile Tables (ACCEPT) Catalog, contains the radial entropy profiles of the intracluster medium (ICM) for a collection of 239 clusters taken from the Chandra X-ray Observatory's Data Archive. Entropy is of great interest because it controls ICM global properties and records the thermal history of a cluster. The authors find that most ICM entropy profiles are well fitted by a model which is a power law at large radii and approaches a constant value at small radii: K(r) = K<sub>0</sub> + K<sub>100</sub> (r/100 kpc)<sup>alpha</sup>, where K<sub>0</sub> quantifies the typical excess of core entropy above the best-fitting power law found at larger radii. The authors also show that the K<sub>0</sub> distributions of both the full archival sample and the primary Highest X-Ray Flux Galaxy Cluster Sample of Reiprich (2001, Ph.D. thesis) are bimodal with a distinct gap between K<sub>0</sub> ~ 30 - 50 keV cm<sup>2</sup> and population peaks at K<sub>0</sub> ~ 15 keV cm<sup>2</sup> and K<sub>0</sub> ~ 150 keV cm<sup>2</sup>. The effects of point-spread function smearing and angular resolution on best-fit K<sub>0</sub> values are investigated using mock Chandra observations and degraded entropy profiles, respectively. The authors find that neither of these effects is sufficient to explain the entropy-profile flattening they measure at small radii. The influence of profile curvature and the number of radial bins on the best-fit K<sub>0</sub> is also considered, and they find no indication that K<sub>0</sub> is significantly impacted by either. All data and results associated with this work are publicly available via the project web site <a href="http://www.pa.msu.edu/astro/MC2/accept/">http://www.pa.msu.edu/astro/MC2/accept/</a>. The sample is collected from observations taken with the Chandra X-ray Observatory and which were publicly available in the CDA (Chandra Data Archive) as of 2008 August. This table was created by the HEASARC in January 2012 based on CDS Catalog J/ApJS/182/12 files table1.dat and table5.dat. This is a service provided by NASA HEASARC .
|