A.M. Rossi

Flavour non-conservation in goldstino interactions

Abstract We point out that the interactions of goldstinos with matter supermultiplets are a potential source of flavour violation, if fermion and sfermion mass matrices are not aligned and supersymmetry is spontaneously broken at a low scale. We study the impact of those couplings on low-energy processes such as μ→eγ , μ→eee , K→μ + μ − , K – K transitions and analogous ones. Moreover, we address the issue of flavour violation in low-energy processes involving two goldstinos and two matter fermions, generalizing earlier results obtained in the flavour-conserving case.

Vacuum oscillation solution to the solar neutrino problem in standard and nonstandard pictures

The neutrino long wavelength (just-so) oscillation is reexamined as a solution to the solar neutrino problem. We consider the just-so scenario in various cases: in the framework of the solar models with a relaxed prediction of the boron neutrino flux, as well as in the presence of the nonstandard weak range interactions between neutrino and matter constituents. We show that the fit of the experimental data in the just-so scenario is not very good for any reasonable value of the {sup 8}B neutrino flux, but it substantially improves if the nonstandard {tau}-neutrino--electron interaction is included. These new interactions could also remove the conflict of the just-so picture with the shape of the SN 1987A neutrino spectrum. Special attention is devoted to the potential of the future real-time solar neutrino detectors such as Super-Kamiokande, SNO, and BOREXINO, which could provide the model-independent tests for the just-so scenario. In particular, these imply a specific deformation of the original solar neutrino energy spectra and time variation of the intermediate energy monochromatic neutrino ({sup 7}Be and pep) signals.

Search for exotic resonances in K−d interactions at 3 GeV/c

Abstract A systematic search for exotic states produced in K − d interactions at 3 GeV/ c is reported. From the analysis of the mass spectra of strange mesons, non-strange mesons, hyperons with S = −1 and S = −2, upper limits for the production cross sections of exotic resonances may be placed at one or two orders of magnitude smaller than for the production of normal resonances of same strangeness and baryon number.

Matter induced neutrino decay and solar antineutrinos

AbstractThe properties of matter-induced neutrino decay with majoron emission are analysed in some details for the cases of Majorana, ZKM and Dirac neutrinos. The result of such a decay of solarves in the sun interior could be the appearance ofn

K−n elastic scattering at 3 GeV/c

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Decay asymmetry of the K− π+ system in K− nucleon interactions at 3 GeV/c

n flux. Assuming that the neutrinos have only standard weak interactions, the solarn

Study of the reactions K-n --> Lambdapi- and K-n --> Sigmaopio at 3 GeV/c

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