Measuring neutrino masses with supernova neutrinos

A new method to study the effects of neutrino masses on a supernova neutrino signal is proposed. The method relies exclusively on the analysis of the full statistics of neutrino events, it is independent of astrophysical assumptions, and does not require the observation of any additional phenomenon to trace possible delays in the neutrino arrival times. A statistics of several thousands of events as could be collected by SuperKamiokande, would allow to explore a neutrino mass range somewhat below 1eV.Comment: 3 pages; contribution to the proceedings of X Marcel Grossmann Meeting, Rio de Janeiro, 20-26 July 200

Naturally large Yukawa hierarchies

The spontaneous breaking of the $SU(3)^5$ quark/lepton flavor symmetry by means of three multiplets of scalar `Yukawa fields' admits vacua with one O(1) and two vanishing vacuum expectation values (vevs) for each multiplet. If the number of generations is equal to three, and only in this case, the vanishing vevs are lifted to exponentially suppressed entries by the inclusion of symmetry invariant logarithmic terms. A strong hierarchy for the Yukawa couplings and a quark mixing matrix that approaches a diagonal form are obtained in a natural way from O(1) parameters. This scenario provides a concrete realization of the minimal flavor violation hypothesis.Comment: 8 pages. Added two references. Section 2a and 3 revised. Results unchange

Quark Yukawa pattern from spontaneous breaking of flavour SU(3)3SU(3)^3

A $SU(3)_Q \times SU(3)_u \times SU(3)_d$ invariant scalar potential breaking spontaneously the quark flavour symmetry can explain the standard model flavour puzzle. The approximate alignment in flavour space of the vacuum expectation values of the up and down `Yukawa fields' results as a dynamical effect. The observed quark mixing angles, the weak CP violating phase, and hierarchical quark masses can be all reproduced at the cost of introducing additional (auxiliary) scalar multiplets, but without the need of introducing hierarchical parameters.Comment: 8 pages. Contribution to the proceedings of the 10th Simposio Latinoamericano de F\'isica de Altas Energ\'ias (X SILAFAE) - Ruta N, Medell\'in, Colombia, November 24-28 201