DOCTORAL DISSERTATION

Written at the Center for Relativity at the University of Texas at Austin.

Neutrino Heating and Baryon Inhomogeneity in Big Bang Nucleosynthesis

• Chapter 1: - Introduction
• Chapter 2: - Comparison of two BBN Codes
• Chapter 3: - The Neutrino Heating Effect
• Chapter 4: - Inhomogeneous Big Bang Nucleosynthesis
• Chapter 5: - Conclusions and Appendix

RESEARCH INTERESTS

Professional Information

Status: Postdoctoral Research Associate at the Department of Physics and Astronomy at Clemson University

Go to the NASA ADS Archives to look up my articles.

Supernova Physics

I have been looking at x-ray and gamma-ray emmisions from Type Ia supernovae.

Certain unstable proton-rich isotopes decay by electron capture, emitting x-rays. In type Ia supernovae there exists the decay line ⁵⁹Cu &rarr ⁵⁹Ni &rarr ⁵⁹Co. I am looking for detection of the x-ray decay line of ⁵⁹Ni in the supernova Tycho. We can make a prediction as to the location of ⁵⁹Ni using theoretical models of TypeIa supernova remnants, and then compare with observation.

For each theoretical model of Type Ia supernovae one can obtain gamma ray line spectra. I am a part of a collaboration with Prof. Mark Leising and Dr. LihSin The of Clemson and Dr. Peter Milne of the University of Arizona at Tuscon Steward Observatory, to determine how well gamma ray line spectra can distinguish between models. We are particularly looking at the decay chain ⁵⁶Ni &rarr ⁵⁶Co &rarr ⁵⁶Fe, seeing how distinctive the light curves, line profiles, and line ratios derived from that chain are for each model. We are trying to determine if the future Advanced Compton Telescope will be able to match a specific model to an actual observation.

Cosmology

Big Bang Nucleosynthesis is the process during the Big Bang wherein free neutrons and protons gradually form heavier nuclei through nuclear reactions and weak decays. BBN produces ⁴He, deuterium, ⁷Li and ⁷Be in significant amounts. For my doctoral dissertation I wrote my own BBN code for a baryon inhomogeneous model of the universe. I worked on calculating the effect of the heating of neutrinos by electron positron scattering and annihilation on nucleosynthesis results. I calculated the effect for both the Standard ( homogeneous and isotrope ) BBN model and the Inhomogeneous BBN model. At Clemson I have continued to look at how the most recent observations of primordial ⁴He, deuterium and ⁷Li+⁷Be look on results from my IBBN code, as individual research in collaboration with Professor Toshitaka Kajino of the National Astronomical Observatory of Japan.

PENDING: The IBBN code used in my journal articles will be made publickly available on this website soon.