Characterization of nuclear recoils up to 300 keV in xenon using a DT neutron source

Xenon Time Projection Chambers (TPCs) continue to be one of the world-leading technologies for Weakly-Interacting Massive Particle (WIMP) dark matter searches.  Canonical WIMP interaction theories predominantly predict lower energy nuclear recoils (<100 keV); however, the absence of any WIMP signal in this energy regime to-date motivates the exploration of new parameter space.  One attractive option is to search for higher energy WIMP interaction signatures, such as those in the 100s of keV range predicted by effective field theory models or inelastic scattering channels. Unfortunately, current charge/light yield calibrations for xenon TPCs only reliably extend to around 100 keV nuclear recoils, with large uncertainties beyond this range.

This talk will present results from a higher energy xenon charge/light yield measurement made with the XeNeu dual-phase xenon TPC at LLNL.  A Deuterium-Tritium source, generating 14.1 MeV neutrons, was used with back-end scintillation detectors to characterize nuclear recoils of xenon at several scattering energies.  The experimental setup will be described, as well as preliminary results from charge/light yield characterizations for up to 300 keV elastic scattering interactions.

This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.