Operation and performance of a dual-phase crystalline/vapor xenon time projection chamber

TL;DR

This paper reports the first operation of a dual-phase crystalline/vapor xenon TPC, demonstrating its potential for improved dark matter searches by background rejection and comparable scintillation yield to liquid xenon.

Contribution

It introduces a novel crystalline/vapor xenon TPC with electroluminescence, showing promising background rejection capabilities and similar scintillation yields to liquid xenon.

Findings

First demonstration of a crystalline/vapor xenon TPC with electroluminescence.

Crystalline xenon scintillation yield is comparable to liquid xenon.

Potential for improved radon background rejection in dark matter detection.

Abstract

We have built and operated a crystalline/vapor xenon TPC, with the goal of improving searches for dark matter. The motivation for this instrument is the fact that beta decays from the radon decay chain to the ground state presently limit the state-of-the-art liquid/vapor xenon experiments. In contrast, a crystalline xenon target has the potential to tag and reject radon-chain backgrounds, due to the time and energy signature of their decays. The present article is the first demonstration of a crystalline/vapor xenon TPC with electroluminescence (gas gain) for the electron signal readout. It also shows that the scintillation yield in crystalline xenon appears to be identical to that in liquid xenon, in contrast to previous results.