Radioactive contamination of BaF2 crystal scintillator

Barium fluoride (BaF 2 ) crystal scintillators are promising detectors to search for double beta decay processes in 130 Ba ( Q 2β = 2619(3) keV) and 132 Ba ( Q 2β = 844(1) keV). The 130 Ba isotope is of particular interest because of the indications on 2β decay found in two geochemical experiments. The radioactive contamination of BaF 2 scintillation crystal with mass of 1.714 kg was measured over 113.4 hours in a low-background DAMA/R&D set-up deep underground (3600 m w.e.) at the Gran Sasso National Laboratories of INFN (LNGS, Italy). The half-life of 212 Po (present in the crystal scintillator due to contamination by radium) was estimated as T 1/2 = 298.8 ± 0.8(stat.) ± 1.4(syst.) ns by analysis of the events pulse profiles.