Evaluation of cosmogenic production of ${}^{39}Ar$ and ${}^{42}Ar$ for rare-event physics using underground argon

Abstract

Underground argon (UAr) with lower cosmogenic activities of ${}^{39}Ar$ and ${}^{42}Ar$ has been planned as a detector in detecting scintillation light and charge collection using time projection chambers for dark matter searches and as a veto detector in suppressing backgrounds for neutrinoless double beta decay (0$\nu \beta \beta$) experiments. Long-lived radioactive isotopes, ${}^{39}Ar$ and ${}^{42}Ar$, can also be produced on the surface when UAr is pumped out from a deep well. Understanding the production of long-lived isotopes in Ar is important for utilizing UAr for dark matter and 0$\nu \beta \beta$ experiments in terms of its production, transportation, and storage. Ar exposure to cosmic rays at sea-level is simulated using Geant4 for a given cosmic ray muon, neutron, and proton energy spectrum. We report the simulated cosmogenic production rates of ${}^{39}Ar$, ${}^{42}Ar$, and other long-lived isotopes at sea-level from fast neutrons, high energy muons, and high energy protons. Total production rates of 938.53/kg${}_{Ar}\cdot$day and 5.81$\times$10${}^{-3}$/kg${}_{Ar}\cdot$day for ${}^{39}$Ar and ${}^{42}$Ar are found from our simulation. Utilizing these production rates, we set a time limit of 954 days constrained by the production of ${}^{39}$Ar for UAr to be on the surface before it compromises the sensitivity for a dark matter experiment. Similarly, a time limit of 1702 days constrained by the production of ${}^{42}$Ar is found for a 0$\nu \beta \beta$ experiment.

12 pages, 3 figures, and 2 tables

References in corpus (12)

• Results from a search for dark matter in the complete LUX exposure
• Dark Matter Candidates from Particle Physics and Methods of Detection
• New results from DAMA/LIBRA
• Results from a Search for Light-Mass Dark Matter with a P-type Point Contact Germanium Detector
• First dark matter search results from a 4-kg CF${}_3$I bubble chamber operated in a deep underground site
• Dark Matter Search Results from the PICO-2L C${}_3$F${}_8$ Bubble Chamber
• Searching for low-mass dark matter particles with a massive Ge bolometer operated above-ground
• Projected WIMP Sensitivity of the XENONnT Dark Matter Experiment
• The LUX-ZEPLIN (LZ) Experiment
• Solar and Atmospheric Neutrinos: Background Sources for the Direct Dark Matter Searches
• LEGEND-1000 Preconceptual Design Report
• The Majorana Demonstrator: A Search for Neutrinoless Double-beta Decay of 76Ge

Cited by in corpus (7)

• Sensitivity projections for a dual-phase argon TPC optimized for light dark matter searches through the ionization channel
• Large Low Background kTon-Scale Liquid Argon Time Projection Chambers
• The science and technology of liquid argon detectors
• Application of the Most Frequent Value Method for ${}^{39}$Ar Half-Life Determination
• Study of cosmogenic activation above ground for the DarkSide-20k experiment
• Study of cosmogenic activation above ground of Ar for DarkSide-20k
• Robust Lifetime Estimation from HPGe Radiation-Sensor Time Series Using Pairwise Ratios and MFV Statistics