Commissioning of the PADME experiment with a positron beam

Abstract The PADME experiment is designed to search for a hypothetical dark photon A ' produced in positron-electron annihilation using bunched positron beam at the Beam Test Facility of INFN Laboratori Nazionali di Frascati. expected sensitivity -photon mixing parameter ? 10 -3 , mass ? 23.5 MeV/ c 2 after collecting ? 13 positrons-on-target. This paper presents detector status commissioning July 2019. In addition, software algorithms employed reconstruct physics objects, such as photons and charged particles, calibration procedures adopted are illustrated detail. results show that experimental apparatus reaches design performance, able identify measure standard electromagnetic processes, bremsstrahlung electron-positron into two photons.