Precision measurements of the scintillation pulse shape for low-energy recoils in liquid xenon

Abstract

We present measurements of the scintillation pulse shape in liquid xenon for nuclear recoils (NR) and electronic recoils (ER) at electric fields of 0 to 0.5 kV/cm for energies $<$ 15 keV and $<$ 70 keV electron-equivalent, respectively. The average pulse shapes are well-described by an effective model with two exponential decay components, where both decay times are fit parameters. We find significant broadening of the pulse for ER due to delayed luminescence from the recombination process. In addition to the effective model, we fit a model describing the recombination luminescence for ER at zero field and obtain good agreement. We estimate the best performance of a combined S2/S1 and pulse shape ER/NR discrimination and show that even with 2 ns time resolution, the improvement over S2/S1 discrimination alone is marginal, so that pulse shape discrimination will likely not be useful for future dual-phase liquid xenon experiments looking for elastic dark matter recoil interactions.

References in corpus (19)

• Results from a search for dark matter in the complete LUX exposure
• Dark Matter Results From 54-Ton-Day Exposure of PandaX-II Experiment
• First Dark Matter Search Results from the XENON1T Experiment
• Liquid Xenon Detectors for Particle Physics and Astrophysics
• The XENON1T Dark Matter Experiment
• Simultaneous Measurement of Ionization and Scintillation from Nuclear Recoils in Liquid Xenon as Target for a Dark Matter Experiment
• Design and Construction of the DEAP-3600 Dark Matter Detector
• Measurements of Scintillation Efficiency and Pulse-Shape for Low Energy Recoils in Liquid Xenon
• A Global Analysis of Light and Charge Yields in Liquid Xenon
• Qualification Tests of the R11410-21 Photomultiplier Tubes for the XENON1T Detector
• Measurement of the refractive index and attenuation length of liquid xenon for its scintillation light
• Liquid xenon scintillation measurements and pulse shape discrimination in the LUX dark matter detector
• Modeling Pulse Characteristics in Xenon with NEST
• Measurement of light and charge yield of low-energy electronic recoils in liquid xenon
• Scintillation-only Based Pulse Shape Discrimination for Nuclear and Electron Recoils in Liquid Xenon
• Scintillation Pulse Shape Discrimination in a Two-Phase Xenon Time Projection Chamber
• A measurement of the time profile of scintillation induced by low energy gamma-rays in liquid xenon with the XMASS-I detector
• A Study of the Scintillation Induced by Alpha Particles and Gamma Rays in Liquid Xenon in an Electric Field
• Commissioning of a dual-phase xenon TPC at Nikhef

Cited by in corpus (8)

• Discrimination of electronic recoils from nuclear recoils in two-phase xenon time projection chambers
• Direct Detection of Dark Matter -- APPEC Committee Report
• Neutral Bremsstrahlung emission in xenon unveiled
• Field dependence of electronic recoil signals in a dual-phase liquid xenon time projection chamber
• GPU-based optical simulation of the DARWIN detector
• Scintillation decay-time constants for alpha particles and electrons in liquid xenon
• Design Challenges for a Future Liquid Xenon Observatory
• On Proportional Scintillation in Very Large LXe Detectors