Modeling Region-Dependent Optical Surface Properties in a Modular Trigger Scintillator for the MOLLER Experiment

Abstract:

The MOLLER experiment at Jefferson Lab sets stringent performance requirements on its trigger scintillation detector system, including uniform spatial efficiency and timing resolution better than 4 ns. As part of an effort to model this system with high fidelity, we investigate the optical photon transport across adjacent scintillator volumes with varying surface finishes using Geant4. A two-slab geometry was designed, with one slab defined as polished and the other as ground, to evaluate whether Geant4 treats their optical interfaces as a continuous volume or introduces artificial boundary effects. The simulation framework is being benchmarked against a physical prototype developed at Louisiana Tech to ensure consistency with measured photoelectron yields and timing responses.