TOF diagnosis of laser accelerated, high-energy protons

Abstract

Significant challenges in the detection of laser-accelerated ions result from the high flux (1010-1012 ions/pulse) and the short bunch duration which are intrinsic to laser-driven sources. The development of diagnostic techniques able to operate in real-time and on a high-rep basis is a key step towards multidisciplinary applications of such non-conventional beams. Real time diagnosis of the main beam parameters for high-energy protons accelerated by the Vulcan Petawatt (VULCAN-PW) laser system has been performed using an on line diagnostics based on the Time of Flight (TOF) technique and the use of diamond detectors. Proton energy spectra have been measured for energies exceeding 30 MeV. The results show that the TOF method employing state-of-the-art detectors is a robust real-time diagnostics, able to operate efficiently under the harsh conditions occurring with kJ-class, PW laser systems, and offering the possibility to monitor on a shot-by-shot basis the main beam parameters of high intensity proton bunches for energies up to the 100 MeV level.