Speaker
Dr
Olga Gileva
(Center for Underground Physics, IBS, Dajeon, KOREA)
Description
The Advanced Mo based Rare process Experiment (AMoRE) searches for neutrinoless double beta decay of 100Mo with the help of molybdate crystals operated as low-temperature scintillation bolometers. Currently, several molybdenum containing compounds, such as 40Ca100MoO4, Li2100MoO4 and Na2100Mo2O7, are considered as possible detectors for the final stage of the experiment, AMoRE-II. For such a rare event search experiment, the techniques for investigating and reducing radioactive background contaminants are extremely crucial. The first step in developing highly radiopure scintillating crystals is deep purification of raw materials used for growing them (MoO3 and carbonates of Ca, Li or Na), that is validated with precise and high-sensitivity radio-assay analyses. For the main component, MoO3, the developed purification technique consists of a sequence of vacuum sublimation, co-precipitation, and complete precipitation of polyammonium molybdates (PAM) from an acidic solution. By the end of 2021, ~100 kg of the 100MoO3 powder is going to be purified using this technique. In addition to the purification of the powder, the residual materials that remain after crystal production must be reconstituted and enriched molybdenum trioxide must be recovered and purified. The purified MoO3 powder has Th and U concentrations that are below the 10 pg/g detection limit for direct ICP-MS measurements. To reach this sensitivity, a sample prepared by an optimized microwave-assisted acid digestion method followed by the application of a solid phase extraction technique with UTEVA resin was used. Details of the radio purification and trace ICP-MS analysis of MoO3 powder performed at Center for Underground Physics (IBS, Korea) will be presented.
Primary author
Dr
Olga Gileva
(Center for Underground Physics, IBS, Dajeon, KOREA)
Co-authors
Prof.
Hong Joo Kim
(2 Department of Physics, Kyungpook National University, Daegu, 41566, Korea)
Dr
Hyang Kyu Park
(Department of Accelerator Science, Korea University, Sejong, 30019, Korea)
Mr
JunSeok Choe
(Center for Underground Physics, IBS, KOREA)
Ms
Keonah Shin
(CUP, IBS)
Dr
Moo Hyun Lee
(Center for Underground Physics, Institute for Basic Science (IBS))
Prof.
Yeongduk Kim
(Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126, Korea)
