Electroluminescence Yield Measurements in Xenon Gas with the NEXT-DEMO++ Detector

TL;DR

This study measures the electroluminescence yield in high-pressure xenon gas using the NEXT-DEMO++ detector, analyzing its pressure dependence to resolve inconsistencies in previous literature.

Contribution

It provides new measurements of EL yield as a function of pressure and electric field, highlighting a modest pressure-dependent change in the yield slope.

Findings

EL yield increases linearly with electric field at various pressures.

The slope of the reduced EL yield changes by about 5% starting around 5 bar.

Pressure influences the EL yield slope, with effects growing up to 9.4 bar.

Abstract

The NEXT-DEMO++ detector, a high-pressure xenon gas time projection chamber serving as a prototype for the NEXT-100 experiment, was used to measure the electroluminescence (EL) yield as a function of reduced electric field ($E/p$) across pressures from 2.0 to 9.4 bar, utilizing the 41.5 keV de-excitation peak of $^{83m}$Kr. These measurements were made to examine the pressure dependence of the slope of the reduced EL yield $Y/p$, which has shown inconsistencies in the literature. The reduced yield was fitted with a linear model, revealing a modest ($\sim$5%) change in slope, beginning around 5 bar and increasing with pressure up to 9.4 bar.