Speaker
Description
Liquid argon detectors are widely used in neutrino physics and dark matter detection through the collection of ionization charge and/or scintillation light produced by particles interacting in the bulk liquid argon. The introduction of hydrocarbon-based photo-ionizing dopant into a liquid argon detector can extend its detection capabilities by lowering the energy threshold for charge collection and improving neutron detection efficiency through neutron capture on Hydrogen. These capabilities can be used for electron antineutrino detection via the inverse beta decay interaction, in-situ neutron flux measurements, and increased sensitivity to low-energy neutrinos produced by supernovae in a detector such as DUNE. An experiment at the Fermilab Noble Liquid Test Facility (NLTF) was performed to understand whether the introduction of a cocktail consisting of Xenon and the photo-ionizing dopant isobutylene (C4H8) could provide a substantial number of free proton targets in a liquid argon volume while simultaneously preserving the scintillation light signal. The experiment ran in the summer of 2024 with different doping configurations at the ppm level studying the impact on the liquid argon scintillation light of isobutylene alone, xenon alone, and then a combination of isobutylene and xenon. This talk will present the results of the recent run along with the prospects for achieving doping concentrations that would be needed in a future liquid argon detector.
