Date of Award

8-2009

Degree Name

Master of Arts

Department

Physics

First Advisor

Dr. Kirk T. Korista

Second Advisor

Dr. Dean Halderson

Third Advisor

Dr. Alan H. Wuosmaa

Access Setting

Masters Thesis-Campus Only

Abstract

My thesis is concerned with an investigation of the mechanism thought to power Quasars: the accretion of gas onto super-massive black holes in the centers of galaxies. I work with a simple model of an accretion disk surrounding a non-rotating black hole, for which I derive theoretical predictions of the local gas temperature as function of disk radius. I have developed a FORTRAN program which queries the user to input key parameters such as mass of the black hole, mass accretion rate, etc. Key characteristics of the luminous accretion disk are computed, such as the maximum disk temperature. Assuming that the disk emits locally like a blackbody, this program then computes the blackbody radiation flux and luminous power as functions of radius through the disk, as well as the radius-integrated total luminous power and its ratio to a theoretical maximum value. Finally, this program computes the accretion disk's integrated luminous spectrum. This spectrum is then plotted and compared to a typical quasar spectrum from the near-infrared to the ultraviolet. I will explore the dependency of this spectrum on key physical parameters such as the mass of the black hole, mass accretion rate, matter-to-energy efficiency, etc.

Share

COinS