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Physical Sciences and Mathematics Commons

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Physics

Astrophysics and Astronomy

Theses/Dissertations

2007

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

Determining The Agn Fraction Of Galaxy Groups, Rachel Paterno-Mahler May 2007

Determining The Agn Fraction Of Galaxy Groups, Rachel Paterno-Mahler

Pomona Senior Theses

Using the Chandra X-ray Observatory, Martini et al. (2006) found that the AGN fraction of galaxy clusters was five times higher than previous optical studies suggested. Using visual observations only, Dressler et al. (1985) estimated the AGN fraction of field galaxies to be 5%, while that of clusters was thought to be 1%. To understand the role that the environment plays in AGN fueling, the author studied a variety of environments, ranging from the field to groups to clusters. Will the AGN fraction of groups also be higher than that of the field? The author demonstrates how the AGN fraction …


Fuzzy Blackholes, Anand Murugan May 2007

Fuzzy Blackholes, Anand Murugan

Pomona Senior Theses

The fuzzball model of a black hole is an attempt to resolve the many paradoxes and puzzles of black hole physics that have revealed themselves over the last century. These badly behaved solutions of general relativity have given physicists one of the few laboratories to test candidate quantum theories of gravity. Though little is known about exactly what lies beyond the event horizon, and what the ultimate fate of matter that falls in to a black hole is, we know a few intriguing and elegant semi-classical results that have kept physicists occupied. Among these are the known black hole entropy …


Coupling Down Converted Light Into Single Mode Fibers, David A. Niemi Apr 2007

Coupling Down Converted Light Into Single Mode Fibers, David A. Niemi

Theses and Dissertations

We investigate the influence of the pump and collection mode parameters on the collection efficiency of Type I down converted photons into single mode fibers. For best single and coincidence counting rates, we find that the mode sizes should be close to the same size and that the mode waists should be located near the down-conversion crystal. Larger collection waists give higher collection efficiencies, but lower singles counts.