Speaker
Description
We study environmental gamma-ray backgrounds relevant to cryogenic bolometer experiments at the China Jinping Underground Laboratory (CJPL). A CZT detector was used to measure the underground gamma spectrum, and a Geant4 model was developed to simulate its response. The deconvolution method is applied to reconstruct the incident gamma flux.
The reconstructed flux is then used as an input for Geant4 simulations of a cryogenic bolometer detector to evaluate background event rates. We further study shielding designs based on lead and copper to reduce external gamma backgrounds, and investigate pile-up effects arising from the slow response of cryogenic bolometers.
This work provides input for background modeling and shielding optimization for future low-background experiments at CJPL.