Production Rate Measurement of Tritium and Other Cosmogenic Isotopes in Germanium with CDMSlite

Understand

Future direct searches for low-mass dark matter particles with germanium detectors, such as SuperCDMS SNOLAB, are expected to be limited by backgrounds from radioactive isotopes activated by cosmogenic radiation inside the germanium.

• There are limited experimental data available to constrain production rates and a large spread of theoretical predictions.
• We examine the calculation of expected production rates, and analyze data from the second run of the CDMS low ionization threshold experiment (CDMSlite) to estimate the rates for several isotopes.
• We model the measured CDMSlite spectrum and fit for contributions from tritium and other isotopes.