Noboru Nakamura | Searcharxiv

arXiv2003

Decoupling and lepton flavor violation in extra dimension

We discuss the fermion mass hierarchy and the flavor mixings in the fat brane scenario of five dimensional SUSY theory. The decoupling solution of the sfermion mass spectrum can be realized by introducing the vector-like mirror fields in an extra dimension. In this scenario, both the left- and right-handed sleptons can have sizable flavor mixings. We point out that this sizable flavor mixings can induce the suitable magnitude of the muon anomalous magnetic moment ($g_μ-2$) within the experimental bounds of lepton flavor violating processes.

hep-ph↗

arXiv2002

Neutrinoless double $β$ decay, neutrino mass hierarchy, and neutrino dark matter

Recently the evidence of the neutrinoless double $β$ ($0νββ$) decay has been announced. This means that neutrinos are Majorana particles and their mass hierarchy is forced to inverted mass hierarchy (Type B) or degenerate mass (Type C) patterns in the diagonal basis of charged lepton mass matrix. We estimate the magnitude of $0νββ$ decay in the degenerate neutrinos including the cosmological constraint of neutrino dark matter, since the inverted mass hierarchy pattern always satisfies the cosmological constraint. The absolute value of neutrino mass is constrained by $0νββ$ experiment or cosmology depending on the relative signs (Majorana CP phases) of neutrino masses.

hep-ph↗