Enhancement of Proton Acceleration from Focusing Targets

Book excerpt: Particle acceleration from laser-plasma interactions has been a vibrant area of research since the discovery of electron and proton beams emitted from high intensity laser-plasma interactions in the 1980s. Since then, a large body of work has developed in pursuit of understanding and controlling the mechanisms that generate these particle beams, as well as the beams themselves. In particular, proton beams have a rich set of applications in the fields of medicine, fusion energy, and fundamental physics that motivates their study. In this thesis, we first discuss the laser technology that has enabled this research. We follow this with detailed information on the design and development of a 100 TW power upgrade to the graduate student-run GHOST laser system for the purposes of conducting repetition-rated laser-plasma experiments. We then outline the physics that drives particle acceleration during the interactions of high intensity lasers and solid targets with a particular focus on target normal sheath acceleration, the most widely studied laser-plasma particle acceleration mechanism. Finally, we describe experiments conducted on the Texas Petawatt Laser system to test an approach to enhance the yield, peak energy, and beam characteristics of proton beams generated by laser-plasma interactions with the use of focusing targets