This letter reports 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 col- lected in the 2021–2022 physics runs. The sensitivity of this search is 2.2×10−13, a factor of 2.4 better than that of the full MEG dataset and obtained in a data taking period of about one fourth that of MEG, thanks to the superior performances of the new detector. The result is consistent with the expec- ted background, yielding an upper limit on the branching ratio of B(µ+ → e+γ) < 1.5 × 10−13 (90 % C.L.). Additional improvements are expected with the data collected during the years 2023–2024. The data-taking will continue in the coming years.
New limit on the μ+->e+γdecay with the MEG II experiment
Cattaneo P;
2025-01-01
Abstract
This letter reports 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 col- lected in the 2021–2022 physics runs. The sensitivity of this search is 2.2×10−13, a factor of 2.4 better than that of the full MEG dataset and obtained in a data taking period of about one fourth that of MEG, thanks to the superior performances of the new detector. The result is consistent with the expec- ted background, yielding an upper limit on the branching ratio of B(µ+ → e+γ) < 1.5 × 10−13 (90 % C.L.). Additional improvements are expected with the data collected during the years 2023–2024. The data-taking will continue in the coming years.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
