Bethe-Salpeter Amplitudes and Static Properties of the Deuteron

Extended calculations of the deuteron's static properties, based on the numerical solution of the Bethe-Salpeter equation, are presented. A formalism is developed, which provides a comparative analysis of the covariant amplitudes in various representations and nonrelativistic wave functions. The magnetic and quadrupole moments of the deuteron are calculated in the Bethe-Salpeter formalism and the role of relativistic corrections is discussed.Comment: 33 pages ([aps]{revtex} style), 9 Postscript figures; (55 pages if [preprint,aps]{revtex} style is used

Neutral-to-charged current events ratio in atmospheric neutrinos and neutrino oscillations

The atmospheric neutrinos produce isolated neutral pions ($\pi^0$-events) mainly in the neutral current interactions. We propose to study the ratios involving $\pi^0$-events and the events induced mainly by the charged currents. This minimizes uncertainties related to the original neutrino fluxes, and in certain cases, also to the cross-sections. Experimental study of these ratios will allow one to check the oscillation solution of the atmospheric neutrino problem and to identify the channel of oscillations. Illustrative analysis of existing data is presented.Comment: LaTeX, 17 pages, 1 figure. Major changes, illustrative analysis of the Super-Kamiokande results is presente