Scintillation efficiency and ionization yield of liquid xenon for mono-energetic nuclear recoils down to 4 keV

TL;DR

This study measures the scintillation efficiency and ionization yield of liquid xenon for nuclear recoils as low as 4 keV, providing crucial data for improving dark matter detection sensitivity.

Contribution

It provides new measurements of Leff and ionization yield at energies down to 4 keV, extending previous data and informing detector calibration for dark matter experiments.

Findings

Leff decreases with decreasing recoil energy below 10 keV

No significant scintillation quenching due to electric field observed

Enhanced understanding of low-energy nuclear recoils in LXe

Abstract

Liquid Xenon (LXe) is an excellent material for experiments designed to detect dark matter in the form of Weakly Interacting Massive Particles (WIMPs). A low energy detection threshold is essential for a sensitive WIMP search. The understanding of the relative scintillation efficiency (Leff) and ionization yield of low energy nuclear recoils in LXe is limited for energies below 10 keV. In this paper, we present new measurements that extend the energy down to 4 keV, finding that Leff decreases with decreasing energy. We also measure the quenching of scintillation efficiency due to the electric field in LXe, finding no significant field dependence.