Scintillating properties of today available lead tungstate crystals

TL;DR

This study characterizes the scintillation properties of available lead tungstate crystals, revealing shorter time constants and higher light yields than previously reported, with implications for high-energy physics detectors.

Contribution

The paper provides a detailed, quantitative analysis of PbWO4 crystal scintillation properties, including temperature effects, with improved measurement techniques that refine existing data.

Findings

Fast component time constant of 2 ns

Light yield increases at lower temperatures

Shorter time constants and higher light yields than literature

Abstract

In the context of the ClearMind project, we measured the scintillating properties, as induced from from gamma ray interactions, of today available PbWO4 crystal. We measured scintillation s yields and time constants by measuring the signal shape measured on a fast photo-multiplier and deconvoluting it from the instrumental effects. For the doped crystals at room temperature, we measured a fast scintillation component, with time constants of 2 ns, 55 percent of the total light yield, and a slow component of 6 ns. We observe a significant increase of the light yield for the slow component when the temperature decreases and simultaneous increase of the time constants, but no increase in the fast component light yield. Our measurements reproduce the main qualitative features of PbWO4 crystals quoted in the literature. Quantitatively though, we measured significantly shorter time constants and larger light yields. This is explained by a rigorous treatment of the instrumental contributions in the measurements. Results are discussed and prospect for future developments, tailored for the ClearMind project, are presented.