Waveform simulation in PandaX-4T

Signal reconstruction through software processing is a crucial component of the background and signal models in the PandaX-4T experiment, which is a multi-tonne dark matter direct search experiment. The accuracy of signal reconstruction is influenced by various detector artifacts, including noise, dark count of photomultiplier, photoionization of impurities in the detector, and other relevant considerations. In this study, we presented a detailed description of a semi-data-driven approach designed to simulate a signal waveform. This work provides a reliable model for the efficiency and bias of the signal reconstruction in the data analysis of PandaX-4T. By comparing critical variables that relate to the temporal shape and hit pattern of the signals, we found good agreement between the simulation and data.