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Black Hole Accretion and X-Ray Variability in AGN.

DE2004833107

Publication Date	2004
Personal Author	Vollrath, Z.
Page Count	28
Abstract	Active Galactic Nuclei (AGN) have very luminous centers which are so bright that the surrounding stars can not adequately account for the energy emission of AGN. One of the most accepted explanations for this energy release is black hole accretion. These black holes accrete near by gas and dust, and as a result gravitational potential is converted to energy which is released. In order to probe the accretion mechanism which lies close to the black hole, short time scale X-ray variability is analyzed. The very short time scale variability will increase understanding of the processes that occur in the heart of galaxies. Data from the ASCA X-ray telescope was reduced and analyzed using the programs FTOOLS, XSELCT, and ASCASCREEN. Light curves and event lists were generated for long term observations of different AGN which were sent to collaborators for further analysis using the event time arrivals. The analysis will compare accretion and jet dominated AGN and will provide use with an understanding of how short scale time variability can relate to the mechanism very close to black holes buried within AGN.
Keywords	Black holes Stars Galaxies Nuclei Probes
Source Agency	Technical Information Center Oak Ridge Tennessee
Corporate Authors	Clemson Univ., SC.; Stanford Linear Accelerator Center, CA.; Department of Energy, Washington, DC.
Supplemental Notes	Prepared in cooperation with Stanford Linear Accelerator Center, CA. Sponsored by Department of Energy, Washington, DC.
Document Type	Technical Report
NTIS Issue Number	200514

Black Hole Accretion and X-Ray Variability in AGN.

Black Hole Accretion and X-Ray Variability in AGN.
DE2004833107

Publication Date	2004
Personal Author	Vollrath, Z.
Page Count	28
Abstract	Active Galactic Nuclei (AGN) have very luminous centers which are so bright that the surrounding stars can not adequately account for the energy emission of AGN. One of the most accepted explanations for this energy release is black hole accretion. These black holes accrete near by gas and dust, and as a result gravitational potential is converted to energy which is released. In order to probe the accretion mechanism which lies close to the black hole, short time scale X-ray variability is analyzed. The very short time scale variability will increase understanding of the processes that occur in the heart of galaxies. Data from the ASCA X-ray telescope was reduced and analyzed using the programs FTOOLS, XSELCT, and ASCASCREEN. Light curves and event lists were generated for long term observations of different AGN which were sent to collaborators for further analysis using the event time arrivals. The analysis will compare accretion and jet dominated AGN and will provide use with an understanding of how short scale time variability can relate to the mechanism very close to black holes buried within AGN.
Keywords	Black holes Stars Galaxies Nuclei Probes
Source Agency	Technical Information Center Oak Ridge Tennessee
Corporate Authors	Clemson Univ., SC.; Stanford Linear Accelerator Center, CA.; Department of Energy, Washington, DC.
Supplemental Notes	Prepared in cooperation with Stanford Linear Accelerator Center, CA. Sponsored by Department of Energy, Washington, DC.
Document Type	Technical Report
NTIS Issue Number	200514