Design and Analysis of Small Angle Monitors for the MOLLER Experiment

The Measurement of a Lepton-Lepton Electroweak Reaction (MOLLER) experiment proposes to measure the parity-violating asymmetry in electron-electron (Møller) scattering, thus offering a precise determination of the weak mixing angle at low energies. This precision will surpass any planned experiments at low energies in the next decade and offer a unique way to explore new physics at different energy scales, complementing searches at high-energy colliders like the Large Hadron Collider (LHC). Achieving precise controls is critical to meet the experiment's ultra-precise measurement goals.This endeavor demands comprehensive understanding of systematic uncertainties. The Small Angle Monitors (SAMs) play an important role in this context. When positioned strategically to minimize expected physics asymmetries relative to the main detectors, the SAMs provide sensitive monitoring of false asymmetries. This presentation provides an overview of the SAMs within the MOLLER setup, emphasizing their design considerations and operational contributions. Experimental results presented will include photoelectron (PE) lightguide testing, single PE calibrations (SPE), and Photomultiplier Tube (PMT) characterizations, thereby illustrating that we are achieving our requirements for this detector system.