Speaker
Description
This study focuses on the Single Event Sensitivity (SES) of the MEGII apparatus concerning a muon's charged Lepton Flavour Violating (cLFV) three-body decay involving an Axion-like particle (ALP). Many theories beyond the Standard Model (SM) predict this decay, which does not exist in the SM. Observing this decay would provide compelling evidence of New Physics.
The decay under investigation is μ⁺ → e⁺ a γ in a V-A chirality configuration. Monte Carlo simulations were conducted within the GEANT4 environment, and data were analyzed using the ROOT-Cern framework. It was determined that a low muon beam rate intensity (Rμ ≃ 1×10⁶ μ/s) and a low photon energy (10 MeV) trigger selection can maximize experimental efficiency and SES. A few days of data collection are sufficient to improve upon the best results for this decay using this optimal configuration.
A sensitivity limit on the ALP decay constant of Fᵥ₋ₐ ≥ 1.52 × 10⁹ GeV @ 95% C.L. was estimated with the statistics collected over the past three years by the MEG collaboration, amounting to 8.7 days of data intake. This limit is more stringent than the current best result. This study demonstrates how this search could enhance the world-leading results in the search for this decay.
