Light WIMP Searches: The Effect of the Uncertainty in Recoil Energy Scale and Quenching Factor

TL;DR

This paper highlights the critical need for accurate recoil energy calibration in liquid xenon detectors for light WIMP searches, criticizing recent sensitivity limits due to calibration uncertainties.

Contribution

It identifies key shortcomings in current measurements of scintillation efficiency and ionization yield, emphasizing calibration's role in reliable WIMP detection.

Findings

Calibration uncertainties undermine WIMP sensitivity limits

Existing measurements of scintillation efficiency are insufficient

Recent sensitivity claims are overly optimistic

Abstract

Taking liquid xenon detectors as a case study, the importance of a robust recoil energy calibration as a prerequisite to a search for light-mass Weakly Interacting Massive Particles (WIMPs) is emphasized. Important shortfalls in the analysis of existing measurements of the relative scintillation efficiency and ionization yield for nuclear recoils in liquid xenon are described, leading to the conclusion that recent attempts to extract light-WIMP sensitivity limits from the XENON10 and XENON100 detectors are premature and overly optimistic.