2017/05/31 by Giovanni Marco Pruna, G. M. Pruna, A. Signer +3 · 23 citations
Physics and Astronomy · #Astrophysics #Bar (unit) #Branching fraction #Dark Matter and Cosmic Phenomena #Electron #Electron–positron annihilation #Fermi Gamma-ray Space Telescope #Hadron #Lepton #Monte Carlo method #Muon #Neutrino Physics Research #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum mechanics #Radiative transfer #hep-ex #hep-ph
paper · pdf · doi:10.1016/j.physletb.2017.07.008
published in Physics Letters B 772, 452-458 (Elsevier BV) · 14 pages, 5 figures, published version
openalex created_date 2017/05/19 · openalex publication_date 2017/07/12 · arxiv created 2017/07/24 · arxiv updated 2017/07/25 · openalex updated_date 2026/08/06
We present a general purpose Monte Carlo program for the calculation of the radiative muon decay μ→eνν¯γ and the radiative decays τ→eνν¯γ and τ→μνν¯γ at next-to-leading order in the Fermi theory. The full dependence on the lepton masses and polarization of the initial-sate lepton are kept. We study the branching ratios for these processes and show that fully-differential next-to-leading order corrections are important for addressing a tension between BaBar's recent measurement of the branching ratio B(τ→eνν¯γ) and the Standard Model prediction. In addition, we study various distributions of the process μ→eνν¯γ and obtain precise predictions for the irreducible background to μ→eγ searches, tailored to the geometry of the MEG detector.