Determination of Mo- and Ca-isotope ratios in (CaMoO4)-Mo-100 crystal for AMoRE-I experiment

Abstract

The first phase of the AMoRE (Advanced Mo-based Rare process Experiment) is to search for neutrinoless doublebeta decay of Mo-100 with calcium molybdate ((CaMoO4)-Mo-100) crystals enriched in Mo-100 and depleted in Ca-48 using a cryogenic technique at Yangyang underground laboratory in Korea. It is important to know Mo-100-and 48Caisotope ratios in (CaMoO4)-Mo-100 crystal to estimate half-life of Mo-100 decays and to 2 nu beta beta. background from Ca-48. We employed the ICP-MS (Inductive Coupled Plasma Mass Spectrometer) to measure Mo-100-and Ca-48-isotope ratios in Ca(100)MoO(4)crystal. The measured results for Mo-100-and Ca-48-isotope ratios in the crystal are (94.6 +/- 2.8)% and (0.00211 +/- 0.00006)%, respectively, where errors are included both statistical and systematic uncertainties. (C) 2017 Elsevier B.V. All rights reserved.