Energy diagnostics of the TOP-IMPLART linac proton beam via radiophotoluminescence of color centers in lithium fluoride

Lithium fluoride crystals have been routinely employed as passive radiation detectors based on radiophotoluminescence to assess the energy characteristics of the TOP-IMPLART linac proton beam during commissioning. This is achieved by leveraging their capability to record full Bragg curves through the stable formation of visible-light-emitting color centers in the LiF crystal lattice due to interactions with incoming protons. Here, a brief overview of the current state of this simple and powerful energy diagnostics method is presented, focusing on the latest improvements made to the theoretical model used for analysis. In particular, a new method to correct the analysis for systematic errors introduced by angular misalignment between the proton beam and the LiF crystal is presented. • Proton irradiation generates spatial distributions of color centers in LiF crystals. • Proton energy is recovered from luminescence of color centers in irradiated LiF. • Proton beam-LiF crystal angular misalignment alters proton energy evaluation. • Post-irradiation angular misalignment correction improves proton energy evaluation.