Speaker
Description
We report the result of the search for the decay µ+ → e+ γ undertaken at the Paul Scherrer
Institut in Switzerland with the MEG II experiment using the data collected in the 2021–2022
physics runs. The MEG II detector consists of a spectrometer built around a solenoidal
magnet delivering a gradient field, consisting of a large cylindrical drift chamber and a
highly segmented timing counter for positron detection, and a large liquid xenon detector
for gamma-ray detection.
The sensitivity of this search improves significantly that obtained with the full MEG dataset,
obtained in a data taking period of about one fourth that of MEG,
thanks to the superior performances of the new detector.
Additional improvements are expected with the data collected during the years 2023–2024.
The data-taking will continue in the coming years.
We report also on the ongoing activity for designing a future experiment for µ+ → e+ detection
with an expected improvement in sensitivity of an additional order of magnitude compared to the
full MEG II data set, based on gamma-ray converter and innovative technology for tracking.
