Precision hadron physis at the Mainz Microtron MAMI and MESA

The Mainz Microtron MAMI is a high-intensity electron accelerator for fixed-target experiments in the fields of hadron and low-energy particle physics. It provides a polarized beam of up to 1.6 GeV beam energy. Two major installations are currently in operation at MAMI: the high-resolution spectrometer setup A1 as well as the A2 detector setup, which consists of the Crystal Ball detector in conjunction with the TAPS calorimeter. Highlights of the research program at MAMI are measurements of the electromagnetic form factors and polarizabilities of the proton, which are related to the proton radius puzzle, the measurement of the transition form factors and slope parameters of the eta meson, as well as the search for hypothetical gauge bosons of the dark sector, also denoted as dark photons. Currently, the new electron accelerator MESA is in preparation at Mainz, which will allow for a precision measurement of the electroweak mixing angle at low momentum transfer as well as measurements of low-energy electron-nucleon/nucleus scattering for various applications in nuclear, hadron, and particle physics.