CCD-based diagnostics for pulsed MeV photon beams

Abstract

Narrow bandwidth, MeV-level photon beams can be generated by Thomson scattering of laser light from fast electrons. Intense photon sources (> 1 MeV, 108 photons/shot) from laser plasma accelerated GeV electrons present the possibility for compact active interrogation devices. However, the characterization of such intense photon beams is inherently challenging due to mm-scale focusing and fs-scale pulse duration. A solution to the characterization of both spatial and energy distributions of each shot is to employ a low mass scattering material and track the scattered Compton electron's direction and energy. Following previous work at UC Berkeley with electron track Compton imaging in fully-depleted silicon CCDs, we present a measurement scheme for the shot-by-shot measurement of MeV photon beam position and energy.