Solar and atmospheric neutrino oscillations and lepton flavor violation in supersymmetric models with right-handed neutrinos

Taking the solar and the atmospheric neutrino experiments into account we discuss the lepton flavor violating processes, such as →τμγ or →μeγ, in the minimal supersymmetric standard model with right-handed neutrinos (MSSMRN) and the supersymmetric SU(5) grand unified theory with right-handed neutrinos [SU(5)RN]. The predicted branching ratio of →μeγ in the MSSMRN with the Mikheyev-Smirnov-Wolfenstein (MSW) large angle solution is so large that it goes beyond the current experimental bound if the second-generation right-handed Majorana mass M_ν₂ is greater than ~10¹³(~10¹⁴)GeV for tanβ=30(3). When we take the MSW small angle solution, the →μeγ rate is at most about 1/100 of that of the MSW large angle solution. The ``just so'' solution implies 10^-5 of that of the MSW large angle solution. Also, in the SU(5)RN the large →μeγ rate naturally follows from the MSW large angle solution, and the predicted rate is beyond the current experimental bound if the typical right-handed Majorana mass MN is larger than ~10¹³(~10¹⁴)GeV for tanβ=30(3), similarly to the MSSMRN. We show the multimass insertion formulas and their applications to →τμγ and →μeγ.