Thesis/Capstone Archive

Year:
Advisor:
Jacob Barker (Senior Thesis, March 2019, Advisor: Justin Peatross )

Abstract

A focused intense laser pulse can rip multiple electrons from atoms. At low density,the liberated electrons move freely in the laser field in response to the Lorentz force. The movement of a charged particle causes electromagnetic radiation to scatter out of the focus. In our lab, we study these laser-particle interactions by looking at the scattered electromagnetic radiation. As the laser intensity increases, electrons can reach relativistic speeds as they oscillate. Few people have intuition for this complex motion and radiation. I developed a computer simulation that animates these interactions in a physically realistic manner. I discuss the physics of these interaction and the development of the simulation. I present several animations of scenarios similar to our experiments

Christoph Schulzke (Senior Thesis, January 2019, Advisor: Justin Peatross )

Abstract

Electrons driven by intense laser fields exhibit nonlinear Thomson scattering. Measuring these radiation patterns has become of interest to many groups including our group at Brigham Young University.The theoretical description of this phenomenon was outlined by Sarachik and Schappert in 1970. The solution for the scattered light involves a numeric integral. They developed an approximation which uses a series of Bessel functions in place of the integral. In this thesis we investigate the efficacy of the Bessel-series approximation to see if gives an advantage over the numerical-integration approach. We find only a modest advantage for certain parameters. Generally, performing the integration numerically is a sensible approach.