Extraction efficiency of drifting electrons in a two-phase xenon time projection chamber

TL;DR

This study measures how efficiently electrons are extracted from liquid to gas in a two-phase xenon detector across various electric fields, indicating potential for improved detector signals with high-voltage optimization.

Contribution

It provides the first detailed measurement of electron extraction efficiency over a range of electric fields in two-phase xenon detectors, highlighting the potential for enhanced charge signals.

Findings

Extraction efficiency increases with higher electric fields.

Efficiency continues to rise at the highest fields tested.

Potential for improved detector performance through high-voltage engineering.

Abstract

We present a measurement of the extraction efficiency of quasi-free electrons from the liquid into the gas phase in a two-phase xenon time-projection chamber. The measurements span a range of electric fields from 2.4 to 7.1 kV/cm in the liquid xenon, corresponding to 4.5 to 13.1 kV/cm in the gaseous xenon. Extraction efficiency continues to increase at the highest extraction fields, implying that additional charge signal may be attained in two-phase xenon detectors through careful high-voltage engineering of the gate-anode region.