We propose a novel probabilistic model for the reconstruction of point-source events, with the dependence of scintillation light time response curve on the number of photoelectrons deduced from first principles. It follows naturally from the time response curve and is unbiased.
The Jiangmen Underground Neutrino Observatory (JUNO) detector is 20 kton underground liquid scintillator detector, with the primary physics goal of determining the neutrino mass hierarchy. At JUNO, the model is applicable to small photomultipliers with first photoelectron time and charge integration readouts, but can also be used for fast reconstruction using large photomultipliers with waveform readouts. We evaluate the performance based on JUNO Monte Carlo simulations.