Neutrino masses and LFV from minimal breaking of U(3)^5 and U(2)^5 flavor symmetries

Abstract

We analyze neutrino masses and Lepton Flavor Violation (LFV) in charged leptons with a minimal ansatz about the breaking of the U(3)^5 flavor symmetry, consistent with the U(2)^3 breaking pattern of quark Yukawa couplings, in the context of supersymmetry. Neutrino masses are expected to be almost degenerate, close to present bounds from cosmology and $0\nu \beta \beta$ experiments. We also predict $s_{13}\approx s_{23}|V_{td}|/|V_{ts}|\approx 0.16$, in perfect agreement with the recent DayaBay result. For slepton masses below 1 TeV, barring accidental cancellations, we expect $\text{cB}(\mu \to e\gamma )>10^{-13}$ and $\text{cB}(\tau \to \mu \gamma )>10^{-9}$, within the reach of future experimental searches.

Comments: 10 pages, 7 figures, v2: Minor changes