Speaker
Description
The Paul Scherrer Institute MUSE experiment was created a decade ago in response to the Proton Radius Puzzle, the difference observed between muonic hydrogen measurements of the proton radius and the existing electronic measurements. MUSE simultaneously scatters electrons and muons from hydrogen, alternating between beam polarities, to directly compare the cross sections and form factors with each probe, and to determine the proton radius for each reaction. The comparison of the + and - beam polarities probes Two-Photon Exchange (TPE). MUSE aims to measure sub-percent-level cross sections, providing electron scattering data at a level similar to other high-precision experiments, muon scattering data an order of magnitude better than previous measurements, and two-photon exchange measurements several times better than any others up to now. To date, MUSE has commissioned its experimental systems to the level needed for the measurements and performed a careful studies of the electron and muon beam properties in the PiM1 channel. In 2021 we obtained a high statistics scattering data set at +/-115 MeV/c. We are currently working on some technical upgrades, analysis, and preparing to obtain production data this fall.
