Seesaw mechanism in magnetic compactifications

In this paper, we explore a new avenue to a natural explanation of the observed tiny neutrino masses with a dynamical realization of the three-generation structure in the neutrino sector. Under the magnetized background based on $T^2/Z_2$, matter consists of multiply-degenerated zero modes and the whole intergenerational structure is dynamically determined. In this sense, we can conclude that our scenario is favored by minimality, where no degree of freedom remains to deform the intergenerational structure by hand freely. Under the consideration of brane-localized Majorana-type mass terms for an $SU(2)_L$ singlet neutrino, it is sufficient to introduce one Higgs doublet for reproducing the observed neutrino data. In all reasonable flux configurations with three right-handed neutrinos, phenomenologically acceptable parameter configurations are found.Comment: 20 pages, 3 figures, 4 tables; published version from JHEP (v2

Chiral Mass Splitting for c \bar{s} and c \bar{n} Mesons in the \tilde{U}(12)-Classification Scheme of Hadrons

We investigate the chiral mass splitting of parity-doubled J=0,1 states for c \bar{s} and c \bar{n} meson systems in the \tilde{U}(12)_{SF}-classification scheme of hadrons, using the linear sigma model to describe the light-quark pseudoscalar and scalar mesons together with the spontaneous breaking of chiral symmetry, and consequently predict the masses of as-yet-unobserved (0^{+},1^{+}) c \bar{n} mesons. We also mention some indications of their existence in the recent published data from the Belle and BABAR Collaborations.Comment: 5 pages, 1 figures, talk at the 11th International Conference on Hadron Spectroscopy, Rio de Janeiro, Brazil, 21-26 Aug 2005, to appear in the Proceeding

The Ds(2317) and Ds(2463) Mesons as Scalar and Axial-Vector Chiralons in the Covariant Level-Classification Scheme

The new narrow mesons observed recently in the final states Ds+ pi0 and Ds*+ pi0 are pointed out to be naturally assigned as the ground-state scalar and axial-vector chiralons in the c sbar system, which would newly appear in the covariant hadron-classification scheme proposed a few years ago.Comment: 8 pages, 1 figure, uses ptptex.st