Status of the PADME experiment

Abstract

Among the theoretical models addressing the dark matter problem, the category based on a secluded sector is attracting increasing interest. The PADME experiment, at the Laboratori Nazionali di Frascati of INFN, is designed to be sensitive to the production of a low mass gauge boson A′ of a new U(1) symmetry holding for dark sector particles and weakly coupled to the Standard Model photon. The DAΦNE Beam-Test Facility at LNF will provide a high intensity, mono-energetic positron beam impinging on a low Z target. The PADME detector will measure with high precision the momentum of the photon, produced along with the A′ boson in e+e− → A′+γ annihilation in the target, thus allowing to measure the A′ mass as the missing mass in the final state. This technique, particularly useful in case of invisible decays of the A′ boson, will be exploited for the first time in a fixed target experiment. Simulation studies predict a sensitivity on the interaction strength (ϵ2 parameter) down to 10−6, in the mass region 1 MeV < MA′ < 23.7 MeV. In this work the physics potential, the experimental strategy and the status of readiness of the experiment will be reviewed.