VIP Seminar

Dr. Alex H. Lumpkin, Fermi National Accelerator Laboratory

"Feasibility of Optical Transition Radiation Imaging for Laser-driven Plasma Accelerator Electron-Beam Diagnostics"

4:00pm, RLM 11.204

Abstract: Recent reports of quasi-monoenergetic laser plasma accelerator (LPA) beams at 2 GeV and 100 MeV demonstrated normalized transverse emittances below 1 mm-mrad and divergences less than 1/gamma in both cases. Such unprecedented LPA beam parameters can, in principle, be addressed by utilizing the properties of optical transition radiation (OTR). In particular, the linearly polarized features of that radiation provide additional beam parameter sensitivity. I propose a set of complementary measurements of beam size and divergence with near-field and far-field OTR imaging, respectively. The feasibility is supported by analytical modeling for beam size sensitivity and divergence sensitivity. Additionally, there is the possibility of coherent aspects of OTR to detect.

We anticipate the signal levels from charges of 100 pC will require a 16-bit cooled CCD or scientific CMOS camera. Other practical challenges of utilizing these techniques with the LPA configurations will also be discussed.