Speaker
Description
The AMoRE experiment is searching for neutrinoless double-beta (0νββ) decay of ¹⁰⁰Mo using enriched molybdate scintillating crystals. AMoRE-I, the following phase of the pilot run, was operated at the Yangyang Underground Laboratory from December 2020 to May 2023. The detector consisted of 18 crystals with a total mass of 6.194 kg, corresponding to an exposure of 8.02 kg·year.
We present a background study based on the AMoRE-I data. The model includes major internal and external background sources. Internal backgrounds arise from radioactive contaminants in the crystals, such as ²³²Th, ²³⁵U, ²³⁸U, ⁴⁰K, and the two-neutrino double-beta decay (2νββ) of ¹⁰⁰Mo, as well as surface contamination of the crystals. External backgrounds include gamma rays from ²²²Rn daughters, neutrons, radiation from the surrounding rock, and shielding materials.
All background sources are simulated using Geant4, and the simulated spectra are compared with the measured beta–gamma energy spectrum to validate the background model.