New interactions in the radiative pion decay

The preliminary results of PIBETA experiment strongly suggest the presence of non V-A anomalous interactions in the radiative pion decay. Without a guiding idea about the nature of these new interactions it is very difficult to interpret and fit experimental data. We assume that they arise as a result of the exchange of new intermediate chiral bosons which interact anomalously with matter. Their mixing with W-bosons leads effectively to a small anomalous weak moment for W. Based on these assumptions, we show that the most general form of the radiative pion decay rate can be parametrized by three new coupling constants of the anomalous interactions.Comment: 7 pages, no figure

On the CVC problem in tau-decay

The preliminary results of PIBETA experiment strongly suggest the presence of non V-A anomalous interactions in the radiative pion decay. We assume that they arise as a result of the exchange of new intermediate chiral spin-1 bosons which interact anomalously with matter. Their contribution into the tau-decay leads to violation of the CVC hypothesis at the same level as detected experimentally.Comment: 5 pages, 1 figur

Predictions for energy distribution and polarization of the positron from the polarized muon decay

The pure lepton decay of the polarized muon is considered, accounting for a new tensor interaction which is outside of the Michel local interactions. This interaction leads to new energy distribution and polarization of the final charged lepton. The presence of such a type of interaction is strongly required for the description of the latest experimental results on the weak radiative pion decay in the full kinematic region. Assuming quark--lepton universality, predictions for a deviation from the Standard Model are made using only one new parameter. They do not contradict the present experimental data and can be verified further in the on-going experiments at PSI and TRIUMF, at least to the level of 3 standard deviations.Comment: 12 pages, no figure