Minicharged Particle Sensitivity of the MAPP Outrigger Detector

Abstract: We present a detailed study of the projected background-free sensitivity of the MAPP Outrigger Detector (OD) to minicharged particles (mCPs) at the High-Luminosity Large Hadron Collider (HL-LHC). As the first upgrade to the MAPP Experiment, the MAPP OD is a standalone detector designed to offer enhanced sensitivity to high-mass mCPs with intermediate effective charges. The MAPP OD is planned for installation in a duct adjacent to the MAPP-1 detector, located between the LHC's UA83 gallery and the beamline. Considering mCP production via the Drell-Yan mechanism and various meson decays, the results show that, at the 95% confidence level, the MAPP OD can extend the experiment's upper mass reach to mCP masses of approximately 200 GeV at the HL-LHC.