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Formulae for t,he capture rates, gamma-neutrino correlations, and angular distributions of recoil in muon capture processes J i -% J, by an unpolarized nucleus for Ji 3 and J , 5 512, with and without change of parity ofnuclearlevels, are given explicitely in ternis of the multipole amplitudes. Relation of helicity amplitudes for muonic atom decay to the multipole amplitudes and to amplitudes introduced by ot,her authors is presented. The derivation is based on kinematics only, and the formulae are strictly valid for the muon capture by any nuclei. The formulae are convenient, for model calculations of partial transitions with realistic nuclear and muon wave functions and for the phenomenological analysis of a weak interaction. S. CIECHANOWICZ and Z. OZIEWICZ, Angular CorrelationAt present, the main problems investigated in the theory of the muon nucleus interaction are as follows : The effects which violate the impulse approximation of FUJII and PRIMAKOPF [Z]2. The shell-model structure of light nuclei. 3. The fundamental nature of the weak muon nucleus interaction, e.g. violation of 4. The contribution of the higher forbiddenesses and the a Z corrections coming froinThe theoretical study of such problems continually needs new calculations of the invariant amplitudes describing the transition under consideration, but the general connection presented here between these amplitudes and observables, i.e. kinematics, IS unaltered. The necessity of the kinematical tables appeared after the important contribution of the interference between the amplitudes of different forbiddenesses had been discovered 121. This interference essentially takes place because of the large momentum transfer in the muon capture reaction. It is obvious that in all effects where such interference appears, the restriction to the terms of one forbiddeness only is not justified. Our formulae take into account the full contribution of higher forbiddeness, i.e. all multipole amplitudes, and show clearly the existence of a kinematical enhancement of higher multipoles. Owing t o meson factories having been started to work recently, it will be possible to obtain more data on the angular correlations in the nuclear muon capture, and these data may well be interpreted with the help of our formulae. Partial wave decomposition of the transition amplitude in terms of the helicity amplitudes, and general formula for a muon capture partial rate are given in sect. 2. With these amplitudes, general formulae for a gamma-neutrino correlation, angular distribution of recoil and circular polarization are presented in sect. 3, where a triple angular correlation is also shortly discussed. I n sect. 4 we have concentrated on a multipole decomposition of the transition amplitude and give connection of the multipole amplitudes with the helicity amplitudes, and with the other decompositions. The effects of 5"-invariance for these amplitudes are also indicated. In sect. 5, the angular correlation coefficients in the processes of lepton capture from K-orbit, Ji +-J,, for...

In this paper, we analyze the scattering of the neutrino beam on the polarized electron target, and predict the effects of two theoretically possible scenarios beyond the Standard Model. In both scenarios, Dirac neutrinos are assumed to be massive.First, we consider how the existence of CP violation phase between the complex vector V and axial A couplings of the Left-handed neutrinos affects the azimuthal dependence of the differential cross section. This asymmetry does not vanish in the massless neutrino limit. The azimuthal angle φ e ′ of outgoing electron momentum is measured with respect to the transverse component of the initial electron polarization η ⊥ e . We indicate the possibility of using the polarized electron target to measure the CP violation in the νµe − scattering. The future superbeam and neutrino factory experiments will provide the unique opportunity for the leptonic CP violation studies, if the large magnetized sampling calorimeters with good event reconstruction capabilities are build.Next, we take into account a scenario with the participation of the exotic scalar S coupling of the Right-handed neutrinos in addition to the standard vector V and axial A couplings of the Lefthanded neutrinos. The main goal is to show how the presence of the R-handed neutrinos, in the above process changes the spectrum of recoil electrons in relation to the expected Standard Model prediction, using the current limits on the non-standard couplings. The interference terms between the standard and exotic couplings in the differential cross section depend on the angle α between the transverse incoming neutrino polarization and the transverse electron polarization of the target, and do not vanish in the limit of massless neutrino. The detection of the dependence on this angle in the energy spectrum of recoil electrons would be a signature of the presence of the R-handed neutrinos in the neutrino-electron scattering. To make this test feasible, the polarized artificial neutrino source needs to be identified.

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In this paper, we analyze the scattering of solar neutrinos on the polarized electron target, and predict how the effect of parity violation in weak interactions may help to distinguish neutrino signal from detector background. We indicate that the knowledge of the Sun motion across the sky is sufficient to predict the day/night asymmetry in the $(\nu_ee^-)$ scattering on the polarized electron target. To make this detection feasible, the polarized electron target for solar neutrinos needs to be build from magnetic materials, e.g. from ferromagnetic iron foils, paramagnetic scintillator crystals or scintillating ferrofluids.Comment: 3 pages, 2 eps figures, revte