Radiation hardness study of liquid scintillator under 80 MeV proton beam irradiations

Abstract

For monitoring the 1.6 GeV high-energy proton beam, used in the CSNS Phase II upgrade project, a liquid scintillator (LS) detector has become a viable option due to its excellent radiation hardness and the possibility of exchanging the LS remotely. This work investigates the effects of radiation damage on LS samples based on linear alkylbenzene (LAB) induced by 80 MeV protons. The study includes absorption, fluorescence spectroscopy, and light output measurement of the LS before and after proton irradiation, with a focus on determining the radiation resistance threshold of the LS. The results show that the performance of the LS is not affected at absorbed doses up to 2.44 $\times$ $10^3$ Gy. This demonstrates its ability to absorb 8.82 $\times$ $10^{12}$ p/cm² 1.6 GeV protons and remain stable. This suggests that a detector based on LS could potentially be used for monitoring the high-energy proton beam of 1.6 GeV in the CSNS Phase II Upgrade Project.