Measurement Of Be-7 And B-8 Solar Neutrinos With Borexino

Borexino is a real-time liquid-scintillator detector for low-energy neutrino spectroscopy located at the Gran Sasso National Laboratories (Italy). Thanks to the unprecedented radiopurity of the target mass it is providing the first direct and simultaneous measurement of the solar neutrino survival probability in both vacuum-dominated (Be-7 nu) and matter-enhanced regions (B-8.) by a single experiment. The measured interaction rates for both the Be-7 and B-8 solar neutrinos are in fair agreement with the SSM predictions in case of the LMA-MSW oscillation solution and a further confirmation of the LMA scenario is provided by the absence of a day-night asymmetry in the Be-7 signal. These experimental results allow to improve the upper limit on the neutrino effective magnetic moment. Calibration campaigns aiming to reduce the systematical errors on fiducial volume definition and detector energy response are presently in progress.