UC Berkeley

Cosmological evidence indicates that nonbaryonic dark matter makes up a quarter of the energy density of the universe. One hypothesis for the particle nature of dark matter is the weakly-interacting massive particle (WIMP). The Large Underground Xenon (LUX) experiment is a dual-phase xenon WIMP search experiment with a 250kg active volume. Computational tools developed to support LUX analyses include data mirroring and a data visualization web portal.

Within the LUX detector, particle interactions produce pulses of scintillation light. A pulse shape discrimination (PSD) technique is shown to help classify interaction events into nuclear recoils and electron recoils based on the time-structure of the pulses. This approach is evaluated in the context of setting limits on inelastic effective field theory (IEFT) dark matter models. Although PSD is not found to provide significant improvement in the limits, LUX is nevertheless able to set world-leading limits on some IEFT models, while limits for other IEFT models are reported here for the first time.