Importance of upgraded energy reconstruction for direct dark matter searches with liquid xenon detectors

TL;DR

This paper emphasizes the importance of upgraded energy reconstruction methods in liquid xenon dark matter detectors, showing that combining photon and electron signals improves accuracy and impacts search results, especially for low-mass dark matter particles.

Contribution

It introduces an improved energy reconstruction approach using both photon and electron signals, enhancing the accuracy of dark matter search results with liquid xenon detectors.

Findings

Reconstructed energies are more accurate with combined signals.

Low-mass dark matter signals are likely in lower energy regions.

Recent XENON100 results are affected by these energy scale considerations.

Abstract

The usual nuclear recoil energy reconstruction employed by liquid xenon dark matter search experiments relies only on the primary scintillation photon signal. Energy reconstruction based on both the photon and electron signals yields a more accurate representation of search results. For a dark matter particle mass m~10 GeV, a nuclear recoil from a scattering event is more likely to be observed in the lower left corner of the typical search box, rather than near the nuclear recoil calibration centroid. In this region of the search box, the actual nuclear recoil energies are smaller than the usual energy scale suggests, by about a factor x2. Recent search results from the XENON100 experiment are discussed in light of these considerations.