2016/05/31 by Stephen F. King, Patrick Otto Ludl
Physics and Astronomy · #Dirac (video compression format) #Fermion #Lepton #MAJORANA #Mass matrix #Massless particle #Mixing (physics) #Neutrino #Neutrino Physics Research #Noncommutative and Quantum Gravity Theories #Particle physics theoretical and experimental studies #Pontecorvo–Maki–Nakagawa–Sakata matrix #hep-ph
paper · pdf · doi:10.1007/jhep06(2016)147
published as JHEP 06 (2016) 147 · 18 pages, 1 figure, small comments added in introduction and section 3, one reference added, version matches publication in JHEP
openalex publication_date 2016/06/01 · openalex created_date 2016/06/24 · arxiv created 2016/07/05 · arxiv updated 2016/07/06 · openalex updated_date 2026/08/05
We discuss the possibility of enforcing a massless Majorana neutrino in the direct and semi-direct approaches to lepton mixing, in which the PMNS matrix is partly predicted by subgroups of a discrete family symmetry, extending previous group searches up to order 1535. We find a phenomenologically viable scheme for the semi-direct approach based on Q(648) which contains Δ(27) and the quaternion group as subgroups. This leads to novel predictions for the first column of the PMNS matrix corresponding to a normal neutrino mass hierarchy with m 1 = 0, and sum rules for the mixing angles and phase which are characterised by the solar angle being on the low side θ 12 ∼ 31° and the Dirac (oscillation) CP phase δ being either about ±45° or ±π.