Summer Projects:

I worked at South Carolina State University through the CNRT program with Dr. Jeniffer Cash on Cataclysmic Variable star systems which are a type of binary star system. The picture below is an artist's rendering of such a system.



More specifcally I am working on Polars which are a subclass of Cataclysmic Variable Stars systems. Polars have a white dwarf/ main sequence star pair like all cataclysmic variable stars. In normal CV's the white dwarf pulls debris from the secondary normal star which is much larger but has less mass. The debris from a normal CV usually creates a whirlpool (called an accretion disk) of stuff revolving around the more massive white dwarf. A good example of an accretion disk is in the above picture. In a Polar the accretion disk is disrupted by the strong magnetic field of the white dwarf and never has a chance to form, Instead the particles follow magnetic field lines as seen in the above picture on the right.The trajectory of the stream is such that the particles gain a tremendous amount of speed before impacting the surface of the white dwarf. This process creates a hot spot at the point of impact on the white dwarf. This point emits intense ultraviolet and x-ray radiation. The goal of the research I am involed in is to better understand the observational data through computer models of the debris stream. Because the system is rotating the debris stream can eclipse the hot spot of the white dwarf depending on the density of the stream. The models I am attempting to create give us an idea of what the column densities are for a given line of sight perspective. Using this data we can determine when the hot spot will be visible and when the it won't be visible to us. We can then compare this data to actual observed data of a Polars and see if we have accuratly modeled its debris stream.




During the summer of 2004 I worked with Dr Ian George at the Goddard Space Flight Center

This work invlolved high energy spectroscopy
of Active Galctic Nuclei
using Chandra X-ray Observatory
Illustration Credit:
V. Beckmann (NASA's GSFC) et al.,
Illustration Credit: Nasa/CXC/CSO


Active Galaxies are galaxies with a supermassive black whole at the center this is called the active galactic nuclei. Super massive means the mass is approximatly a billion times the mass of the sun.Just to give you a reference the sun's mass is 20000000000000000000000000000000 kg, or 2x10^30kg. Now multiply this number by 1 billion and you will have an estimate for the mass of these black wholes. The black hole in an AGN is surrounded by an accretion disk that emits strong x-rays. The acretion disc is spinning very fast such that the emission from it is red shifted on the side moving away from us and blue shifted on the side moving towards is. Outside the accretion disc is a giant donut shaped cloud of crap, that surrounds the central black hole, called the Taurus. There are four types of active galaxies; Quasars(the most well known), Seyfert 1's, Seyfert 2's, and Blasars. The difference between them is now thought to be because of their orientation relative to us. Look at the above picture of the AGN now image looking at it tilted 45 degrees in your direction. We could probably see alot more of the stuff comming out of the black wholes and the accretion disc that surrounds it. If we were looking at an AGN oriented as the picture shows we would only be able to see the em radiation that can penetrate the taurus. I mainly worked with the two Seyfert type galaxies. These are known for their interesting spectral features.

Home