Sugawara, Chika, Takizawa, Motokazu, Nakazawa, Kazuhiro
We present the results of Suzaku observation of the radio halo cluster Abell 2319. The metal abundance in the central cool region is found to be higher than the surrounding region, which was not...
Hard X-ray properties of the merging cluster Abell 3667 as observed with Suzaku (2009)
Nakazawa, Kazuhiro, Sarazin, Craig L., Kawaharada, Madoka, Kitaguchi, Takao, Okuyama, Sho, Makishima, Kazuo, ...
Hard X-ray Properties of the Merging Cluster Abell 3667 as Observed with Suzaku (2008)
Nakazawa, Kazuhiro, Sarazin, Craig L., Kawaharada, Madoka, Kitaguchi, Takao, Okuyama, Sho, Makishima, Kazuo, ...
Wide-band Suzaku data on the merging cluster Abell 3667 were examined for hard X-ray emission in excess to the known thermal component. Suzaku detected X-ray signals in the wide energy band from 0.5...
We present results from N-body + magnetohydrodynamical simulations of merging clusters of galaxies. We find that cluster mergers cause various characteristic magnetic field structures because of the...
Suzaku Observation of the Ophiuchus Galaxy Cluster: One of the Hottest Cool Core Clusters (2008)
Fujita, Yutaka, Hayashida, Kiyoshi, Nagai, Masaaki, Inoue, Susumu, Matsumoto, Hironori, Okabe, Nobuhiro, ...
We present the analysis of a Suzaku observation of the Ophiuchus galaxy cluster. We confirmed that the cluster has a cool core. While the temperature of the intracluster medium (ICM) decreases toward...
Fujita, Yutaka, Tawa, Noriaki, Hayashida, Kiyoshi, Takizawa, Motokazu, Matsumoto, Hironori, Okabe, Nobuhiro, ...
We present an analysis of a Suzaku observation of the link region between the galaxy clusters A399 and A401. We obtained the metallicity of the intracluster medium (ICM) up to the cluster virial...
We investigate the X-ray and mass distribution in the merging galaxy cluster 1E 0657-56. We study head-on collisions of two virialized clusters with an NFW density profile in the $\Lambda$CDM...
We perform three dimensional hydrodynamical simulations of a moving substructure in a cluster of galaxies. We investigate dynamical evolution of the intracluster medium (ICM) in and around the...
Turbulence Generation by Substructure Motion in Clusters of Galaxies (2005)
Clusters of galaxies form through major merger and/or absorption of smaller groups. In fact, some characteristic structures such as cold fronts, which are likely relevant to moving substructures, are...
Chandra Observations of the Central Region of Abell 3112 (2003)
Takizawa, Motokazu, Sarazin, Craig L., Blanton, Elizabeth L., Taylor, Greg B.
We present the results of a {\it Chandra} observation of the central region of Abell 3112. This cluster has a powerful radio source in the center and was believed to have a strong cooling flow. The...
Nonthermal Emissions from Particles Accelerated by Turbulence in Clusters of Galaxies (2002)
Fujita, Yutaka, Takizawa, Motokazu, Sarazin, Craig L.
We consider nonthermal emission from clusters of galaxies produced by particle acceleration by resonant scattering of Alfv\'{e}n waves driven by fluid turbulence through the Lighthill mechanism in...
Radio Halo Formation through Magneto-turbulent Particle Acceleration in Clusters of Galaxies (2002)
Ohno, Hiroshi, Takizawa, Motokazu, Shibata, Shinpei
We developed a magneto-turbulent model for the cosmic ray (CR) electrons seen in the radio halo clusters of galaxies. Steady state momentum distribution functions of the CR electrons are calculated...
We have calculated evolution of a non-thermal electron population from super-thermal but weakly relativistic to highly relativistic energy range in clusters of galaxies. We investigate evolution of...
Takizawa, Motokazu, Naito, Tsuguya
We have investigated evolution of non-thermal emission from relativistic electrons accelerated at around the shock fronts during merger of clusters of galaxies. We estimate synchrotron radio emission...
We investigate the dynamical evolution of clusters of galaxies and their observational consequences during off-center mergers, explicitly considering the relaxation process between ions and electrons...
Time evolution of galactic warps in prolate haloes (1999)
Ideta, Makoto, Hozumi, Shunsuke, Tsuchiya, Toshio, Takizawa, Motokazu
A recent observation with the Hipparcos satellite and some numerical simulations imply that the interaction between an oblate halo and a disc is inappropriate for the persistence of galactic warps....
Is Galactic Star Formation Activity Increased During Cluster Mergers? (1999)
Fujita, Yutaka, Takizawa, Motokazu, Nagashima, Masahiro, Enoki, Motohiro
We have investigated the effect of pressure from intracluster medium (ICM) on disk galaxies in merging clusters. The ram-pressure on the galaxies rapidly increases when two clusters collide. This...
Two-Temperature Intracluster Medium in Merging Clusters of Galaxies (1999)
We investigate the evolution of intracluster medium during a cluster merger, explicitly considering the relaxation process between the ions and electrons by N-body and hydrodynamical simulations....
A Two-Temperature Model of the Intracluster Medium (1998)
We investigate evolution of the intracluster medium (ICM), considering the relaxation process between the ions and electrons. According to the standard scenario of structure formation, ICM is heated...
Evolution of X-Ray Clusters of Galaxies and Shock Heating of Intracluster Medium (1997)
Takizawa, Motokazu, Mineshige, Shin
Evolutions of X-ray clusters of galaxies are studied by N-body (shell model) + mesh code (TVD) simulations on the assumption of spherical symmetry. We consider a density perturbation of $10^{15}...
Violent Relaxation of Spherical Stellar Systems (1997)
Takizawa, Motokazu, Inagaki, Shogo
Violent relaxation process of spherical stellar systems is examined by numerical simulations of shell model. The collapse of uniform density sphere both with and without external force is...