Speaker
Mr
Jinhong Shen
(Peking University)
Description
We study a light scalar $\phi$ with lepton-flavor-violating $e$–$\mu$ couplings, directly probed via resonant $\mu^+ e^- \to \phi$ production at high-intensity muon beams. In fixed-target experiments, target electrons are bound and have relativistic momenta, which smear and broaden the resonance. We develop a fully relativistic bound-state framework that accounts for these atomic effects and accurately predicts production rates. Our projections show that HIAF can probe couplings down to $\mathcal{O}(10^{-5})$ with short runs, demonstrating strong sensitivity complementary to traditional LFV searches.
Primary authors
Mr
Jinhong Shen
(Peking University)
Mr
Leyun Gao
(Peking University)
