Radiation Hardness Test of Eljen EJ-500 Optical Cement

TL;DR

This study evaluates the proton radiation hardness of Eljen EJ-500 optical cement used in detectors, showing damage increases with dose but partially recovers after four months.

Contribution

First comprehensive assessment of EJ-500's radiation hardness with long-term recovery data using proton irradiation and cosmic ray measurements.

Findings

Radiation damage correlates with dose level.

Partial recovery observed after four months.

Damage remains manageable for detector applications.

Abstract

We present a comprehensive account of the proton radiation hardness of Eljen Technology's EJ-500 optical cement used in the construction of experiment detectors. The cement was embedded into five plastic scintillator tiles which were each exposed to one of five different levels of radiation by a 50 MeV proton beam produced at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. A cosmic ray telescope setup was used to measure signal amplitudes before and after irradiation. Another post-radiation measurement was taken four months after the experiment to investigate whether the radiation damage to the cement recovers after a short amount of time. We verified that the radiation damage to the tiles increased with increasing dose but showed significant improvement after the four months time interval.