Speaker
Description
The LUX-ZEPLIN (LZ) experiment operates a dual-phase xenon time projection chamber with a 7-tonne active mass, which detects both scintillation photons (S1) and ionization electrons (S2) from particle interactions. LZ has recently placed world-leading limits on dark matter-nucleon scattering cross sections for masses down to 5 GeV/$c^2$ and reported 4.5𝜎 evidence of coherent elastic neutrino-nucleus scattering (CE𝜈NS) from $^8$B solar neutrinos. These results rely on robust modeling of low-energy detector backgrounds, which can mimic signal events. The dominant background in this regime arises from accidental coincidences of “isolated” S1- and S2-like pulses, which are produced by various instrumental effects. In this talk, I will describe the construction of an accidental background model that accounts for the time dependence of these effects, and present a series of validations that demonstrate excellent agreement with data down to keV-scale recoil energies.
| Main Contribution topic | Direct detection |
|---|---|
| Secondary contribution topic | Astrophysical observations |