Background Modelling for the TEXONO Coherent Neutrino Scattering Reactor Experiment

We present a background model for TEXONO experiment that is situated in the Kuo-Sheng Neutrino Laboratory. The model includes background contributions from both internal and external contamination. We have adopted the Geant4-based simulation framework to develop the background model, taking into account all contributions from nine radioactive nuclides: \(^{40}\) K, \(^{208}\) Tl, \(^{210}\) Pb, \(^{212}\) Bi, \(^{212}\) Pb, \(^{214}\) Bi, \(^{226}\) Ra, \(^{228}\) Ac and \(^{234}\) Th which are identified from the experimental reference data. The airborne radioactive nuclides related to reactor is also included in this study. Intensive studies are ongoing to incorporate the cosmic-ray induced background into the models.