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We present analysis results for a nearby galaxy cluster Abell 1631 at $z~=~0.046$ using the X-ray observatory Suzaku. This cluster is categorized as a low X-ray surface brightness cluster. To study the dynamical state of the cluster, we conduct four-pointed Suzaku observations and investigate physical properties of the Mpc-scale hot gas associated with the A1631 cluster for the first time. Unlike relaxed clusters, the X-ray image shows no strong peak at the center and an irregular morphology. We perform spectral analysis and investigate the radial profiles of the gas temperature, density, and entropy out to approximately 1.5~Mpc in the east, north, west, and south directions by combining with the XMM-Newton data archive. The measured gas density in the central region is relatively low (${rm a~few} times~10^{-4}~{rm cm^{-3}}$) at the given temperature ($sim2.9~{rm keV}$) compared with X-ray-selected clusters. The entropy profile and value within the central region ($r<0.1~r_{200}$) are found to be flatter and higher ($gtrsim400~ {rm keV~cm}^2$). The observed bolometric luminosity is approximately three times lower than that expected from the luminosity-temperature relation in previous studies for relaxed clusters. These features are also observed in another low surface brightness cluster, Abell 76. The spatial distributions of galaxies and the hot gas appear to be different. The X-ray luminosity is relatively lower than that expected from the velocity dispersion. A post-merger scenario may explain the observed results.
We present 3.6 and 4.5 micron Spitzer IRAC imaging over 0.77 square degrees at the Virgo cluster core for the purpose of understanding the formation mechanisms of the low surface brightness intracluster light features. Instrumental and astrophysical
We report Suzaku observations of the galaxy cluster Abell 1795 that extend to r_200 ~ 2 Mpc, the radius within which the mean cluster mass density is 200 times the cosmic critical density. These observations are the first to probe the state of the in
The results from Suzaku XIS observations of the relaxed cluster of galaxies Abell2052 are presented. Offset pointing data are used to estimate the Galactic foreground emission in the direction to the cluster. Significant soft X-ray excess emission ab
Abell 548W, one of the galaxy clusters located in the Abell 548 region, has about an order of magnitude lower X-ray luminosity compared to ordinal clusters in view of the well known intracluster medium (ICM) temperature vs X-ray luminosity (kT-L_X) r
The results of Suzaku observations of the outskirts of Abell 3395 including a large-scale structure filament toward Abell 3391 are presented. We measured temperature and abundance distributions from the southern outskirt of Abell 3395 to the north at