A study of radiation tolerance in optical cements

TL;DR

This study evaluates how ionizing radiation affects light transmission in optical epoxies, revealing significant degradation in traditional types but identifying a more radiation-tolerant epoxy suitable for high-radiation environments.

Contribution

The paper compares radiation effects on various optical epoxies and identifies a new epoxy with superior radiation tolerance for optical applications.

Findings

Traditional epoxies degrade significantly at high radiation doses.

Degradation progresses from UV to longer wavelengths with increasing dose.

A specific epoxy shows minimal degradation up to high radiation levels.

Abstract

We study the effect ionizing radiation has on light transmission in the wavelength range 190--1100~nm for a number of optically clear epoxies. We find that the transmittance of traditional, commercially available, optical epoxies show significant degradation for exposures of $1\times10^{12}$~MIPs/cm$^2$. Degradation of light transmission progresses from the shortest wavelengths at low doses to longer wavelengths as the dose increases. In epoxy joints that are 0.1~mm thick, we observe that more than 5\% of the light is lost for wavelengths less than 400~nm for traditional optical epoxies. Our studies have identified an optically clear epoxy that shows little degradation for radiation exposures up to $5.9\times 10^{14}$~MIPs/cm$^2$ ($\approx 220$~kGy).