2020/05/31 by G. Hernández-Tomé, J. I. Illana, M. Masip
Physics and Astronomy · #Amplitude #Dark Matter and Cosmic Phenomena #Decoupling (probability) #Electron #Higgs boson #Lepton #Neutrino #Neutrino Physics Research #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum mechanics #Yukawa potential #hep-ph
paper · pdf · doi:10.1103/physrevd.102.113006
published as Phys. Rev. D 102, 113006 (2020) · Comments and references added, version accepted for publication in PRD
arxiv created 2020/12/03 · openalex created_date 2020/12/07 · openalex publication_date 2020/12/21 · arxiv updated 2021/01/04 · openalex updated_date 2026/08/05
The presence of massive sterile neutrinos N mixed with the active ones induces flavor violating processes in the charged lepton sector at the loop level. In particular, the amplitude of H0\ensuremath→\ensuremathℓi\ensuremathℓj is expected to be proportional to the product of heavy-light Yukawa couplings yiyj=2s_\ensuremathνis_\ensuremathνjmN2/v2, where s_\ensuremathνi,j express the heavy-light neutrino mixings. Here, we revisit these Higgs decays in the most generic extension of the neutrino sector, focusing on large values of yi. We show that decoupling effects and a cancellation between the two dominant contributions to these processes makes the amplitude about 100 times smaller than anticipated. We find that perturbative values of yi giving an acceptable contribution to the \ensuremathρ parameter imply B(H0\ensuremath→\ensuremathℓi\ensuremathℓj)<10^\ensuremath-8 for any lepton flavors, a rate that is not accessible at current colliders.