Characterization of alpha and beta interactions in liquid xenon

TL;DR

This paper investigates the scintillation and ionization responses of liquid xenon to low-energy electrons and alpha particles, providing detailed measurements and simulations crucial for rare event detection accuracy.

Contribution

It offers new measurements of light and charge yields and electron drift velocity in liquid xenon, along with a detailed simulation of the electric field homogeneity.

Findings

Measured light and charge yields for electrons and alpha particles.

Determined electron drift velocity across various electric fields.

Simulated electric field homogeneity using COMSOL Multiphysics.

Abstract

Liquid xenon based detectors have achieved great sensitivities in rare event searches. Precise knowledge of the scintillation and ionization responses of the medium is essential to correctly model different interaction types in the detector including both signal and background-like ones. The response of liquid xenon to low energy electrons and to alpha particles has been studied in the Heidelberg Xenon (HeXe) dual-phase xenon TPC. We determine the light and charge signal yields for keV-energy electrons and MeV-energy alpha particles as well as the electron drift velocity for electric drift fields between 7.5 and 1640 V/cm. A three dimensional simulation using COMSOL Multiphysics(R) is used to characterize the applied drift field and its homogeneity.