Massimiliano Bonamente, Nicole Hasler, Esra Bulbul, John E. Carlstrom, Thomas L. Culverhouse, Megan Gralla, Christopher Greer, David Hawkins, Ryan Hennessy, Marshall Joy, Jeffery Kolodziejczak, James W. Lamb, David Landry, Erik M. Leitch, Daniel P. Marrone, Amber Miller, Tony Mroczkowski, Stephen Muchovej, Thomas Plagge, Clem Pryke, Matthew Sharp, David Woody
We present Sunyaev-Zel'dovich (SZ) effect observations of a sample of 25
massive relaxed galaxy clusters observed with the Sunyaev-Zel'dovich Array
(SZA), an 8-element interferometer that is part of the Combined Array for
Research in Millimeter-wave Astronomy (CARMA). We perform an analysis of new
SZA data and archival Chandra observations of this sample to investigate the
integrated pressure -- a proxy for cluster mass -- determined from X-ray and SZ
observations, two independent probes of the intra-cluster medium. This analysis
makes use of a model for the intra-cluster medium introduced by Bulbul (2010)
which can be applied simultaneously to SZ and X-ray data. With this model, we
estimate the pressure profile for each cluster using a joint analysis of the SZ
and X-ray data, and using the SZ data alone. We find that the integrated
pressures measured from X-ray and SZ data are consistent. This conclusion is in
agreement with recent results obtained using WMAP and Planck data, confirming
that SZ and X-ray observations of massive clusters detect the same amount of
thermal pressure from the intra-cluster medium. To test for possible biases
introduced by our choice of model, we also fit the SZ data using the universal
pressure profile proposed by Arnaud (2010), and find consistency between the
two models out to r500 in the pressure profiles and integrated pressures.
View original:
http://arxiv.org/abs/1112.1599
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