Study Of High Energy Astrophysical Processes In Galaxy Clusters And Black Holes

The thesis studies several important high energy astrophysical processes in galaxyclusters and super-massive black holes (SMBHs).Electrons in the fully ionized intracluster medium (ICM) hot gas will change theenergy spectrum of cosmic microwave background by Compton scattering. This so-called Sunyaev-Zel'dovich effect (SZE) is a unique tool for the study of cosmologyand structure and evolution of galaxy clusters. We explore the modification mech-anism of intracluster magnetic fields on the classical SZE. Such magnetic SZ effect(MSZE) tends to enhance the SZE signal with a steeper radial profile. By applyingthe MSZE model to spectral observations of SZE signals and X-ray emissions fromthe galaxy clusters, the intracluster magnetic field can be constrained, i.e., a～30μGcentral magnetic field is predicted for the galaxy cluster A2163. We analyze the three-year data of WMAP satellite, find SZE signal of 10σsignificance in a sample of galaxyclusters. Combined SZ and X-ray data fitting require the outer edge of ICM distribu-tion at cluster virial radius, which could be the evidence of virilization shock aroundthe clusters. We confirm the previous results that the baryons fraction in clusters islower than the cosmic mean value. The existence of the MSZE and an outer edge ofICM distribution bear important systematic uncertainty for cluster-based estimation ofcosmological parameters.Galaxy clusters are the astrophysical laboratory for the study of dark mat-ter. The collision between dark matter particles (DMPs) and baryons is a possi-ble heating source accounting for the absence of over-cooling gas in the central re-gions of"cooling ?ow"clusters. We examine this mechanism in a sample of clus-ters and derive the upper limit for the collisional cross section per DMP mass asσxp/mx～< 2×10?25 cm2 GeV?1. The stability analysis on the energy equilibriumequation of ICM demonstrates that the DMPs-baryons collision cannot be the domi-nant heating source in the center of"cooling ?ow"clusters. We calculate the equiva- lent"temperature"(velocity dispersion) profiles of dark matter in a sample of 21 galaxyclusters with X-ray observations of high spatial and spectral resolution. The dark mat-ter is found to be cooler than the ICM in part of clusters, indicating the existence ofnon-gravitational heating mechanism for ICM.The formation problem of SMBHs in the center of galaxies are crucial for thestudy of galaxy formation and evolution, and cosmic reionization. We proposed theSMBHs quick formation mechanism by two-phase accretion of self-interacting darkmatter and baryons in the early universe, thus explain the formation of quasar SDSS1148+5251, and predict the existence of massive black holes dwelling in the centerof dark galaxies. We also model the dynamics of quasar system HE 0450-2958 andexplain the processes of its SMBH formation and star-burst in the companion galaxy,show that the quasar is triggered by the strong interaction in the high-speed encounterwith the companion galaxy.