Correlated Fluctuations between Luminescence and Ionization in Liquid Xenon

TL;DR

This study reveals a strong anti-correlation between luminescence and ionization fluctuations in liquid xenon, providing insights into electron-ion recombination effects and enabling improved energy resolution in radiation detection.

Contribution

First experimental measurement of anti-correlation between scintillation and ionization in liquid xenon at a microscopic level.

Findings

Strong anti-correlation coefficient between -0.80 and -0.60.

Electron-ion recombination partially explains large fluctuations.

Potential for enhanced calorimetric energy resolution.

Abstract

The ionization of liquefied noble gases by radiation is known to be accompanied by fluctuations much larger than predicted by Poisson statistics. We have studied the fluctuations of both scintillation and ionization in liquid xenon and have measured, for the first time, a strong anti-correlation between the two at a microscopic level, with coefficient $ -0.80 < \rho_{ep} < -0.60 $. This provides direct experimental evidence that electron-ion recombination is partially responsible for the anomalously large fluctuations and at the same time allows substantial improvement of calorimetric energy resolution.