Seasonal variations of the Be-7 solar neutrino flux - art. no. 093011

Measuring the Be-7 solar neutrino flux is crucial towards solving the solar neutrino puzzle. The Borexino experiment, and possibly the KamLAND experim ent, will be capable of studying the 7Be neutrinos in the near future. We d iscuss (1) how the seasonal variation of the Borexino and KamLAND data can be used to measure the 7Be solar neutrino flux in a background independent way and (2) how anomalous seasonal variations might be used to discover vac uum neutrino oscillations, independent of the solar model and the measureme nt of the background. In particular, we find that, after three years of Bor exino or KamLAND running, vacuum neutrino oscillations can be either establ ished or excluded for almost all values of (sin(2) 2 theta,Delta m(2)) pref erred by the Homestake, GALLEX, SAGE, and Super-Kamiokande data. We also di scuss how well seasonal variations of the data can be used to measure (sin( 2) 2 theta,Delta m(2)) in the case of vacuum oscillations. [S0556-2821(99)0 4719-0].