An analysis of radiative decays of the neutrions and of Diarc neutrino magneticmoments is discussed in minimal supersymmetric standard model extensions with a vectorlike lepton generation. Also within the same framework, a discussion of the electron anomalous magnetic moment iscarried outto probe thepossibility of new physics beyond the standard model. Starting withtheradiativedecayof cosmic background neutrinos, we compute neutrino decays arising from the exange ofcharginosandcharged sleptons where the photon isemittedby the charged particle in the loop. It is shown that while the lifetime ofthe neutrino decayin the standard model is 1043 yrs for a neutrinomass of 50meV, the current lower limit fromexperiment from the analysis of the Cosmic Infrared Background is 1012 yrs and thus beyond the reach of expirement in the foreseeable future. However, in the extensions with a vectorlike lepton generation the lifetime for the decays can be as low as 1012 - 1014 yrs and thus within reach of future improved experiments. The effect pf CP phases on the neutrino lifetime is also analyzed. It is shown that while boththe magnetic and the electric transition dipole moments contribute to the neutrino lifetime, often the electric dipole moment dominates even for moderate size CP phases. An analysis of the Diarc neutrino magnetic moment with standard model interactions gives 3x10-19B(m /1eV). The observationof a significantly larger magnetic moment will provide a clear signal of new physics beyond the standard model. The current experimental limits on the neutrino magnetic moments are orders of magnitude larger than the prediction with the standard model interactions and thus its test appears out of reach. Specifically we compute the moments arising from the exchange of W and the charged leptons in the loop, as well as from the exanche of charginos, charged sleptons and charged mirror sleptons. It is shown that the neutrinomoment in this case can be several orders of magnitude larger than the one with standard-model-like interactions, lying close to and below the current experimental upper limits and should be accessible in improved future experiment. A correlated prediction of the heaviest neutrino lifetimes from radiative decays to the lighter neutrinos via exchange of charginos and sleptons in the loops is also made. Asa shown in the seperate analysis, here too, the predicted lifetimes are several orders of magnitudes smaller than the one with the standard model interactions and also lie close to the current experimental limits from analyses using the cosmic background neutrino data. The anomalous magnetic moment of the electron is determined experimentally with an accuracy of 2.8x10-13 and the uncertainty may decresae by an order of magnitude in the future. While the current data is in excellent agreement with the standard model, the possible future improvement in the error in has recently drawn interest in the electron anomalous magnetic moment as a possible probe of new physics beyond the standard model. In the extended model the electroweak contribution to the anomalous magnetic moment of the electron include loop diagrams involving in addition to the exchange of neutralinos, sleptons and mirror sleptons. The analysis shows that a contribution to the electron magnetic moment mucch larger than expected by m2e/m2 scaling of the deviation of the muon anomalous magnetic moment over the standard model prediction, i.e., =3 x 10-9 as given by the Brookhaven experiment, can be gotten within the MSSM extension. Effects of CP violating phases in the extended MSSM model on the corrections to the supersymmetric electroweak contributions to ae are also investigated. The analysis points to possibility of detection of new physics effects with modest improvement on the error in ∆𝑎_𝑒 = 𝑎_𝑒 exp -𝑎_𝑒 theory