Neutrino Oscillations and Flavor Structure of Supersymmetry without   R-Parity
  Focusing on a simple three neutrino oscillation scenario motivated by the recent Super-Kamiokande result, we discuss both tree-level and 1-loop contributions to neutrino masses in supersymmetry without R-parity, aiming at discerning the flavor structure issues of the theory. The single-VEV parametrization framework, which allows the first consistent treatment of the bilinear and trilinear R-parity violating terms, and hence the tree and 1-loop contributions, without any assumption on the nature of R-parity violation. Though the very small neutrino masses implies stringent suppressions of the relevant R-parity violating couplings, we show that there is still room for understanding the suppressions as a simple consequence of the general flavor hierarchy. 
Otto C. W. Kong (Rochester U.)