We report the direct measurement of the 7 Be solar neutrino signal rate performed with the Borexino detector at the Laboratori Nazionali del Gran Sasso. The interaction rate of the 0.862 MeV Be-7 neutrinos is 49 +/- 3(stat) +/- 4(syst) counts/(day . 100 ton). The hypothesis of no oscillation for Be-7 solar neutrinos is inconsistent with our measurement at the 4 sigma C.L. Our result is the first direct measurement of the survival probability for solar P, in the transition region between matter-enhanced and vacuum-driven oscillations. The measurement improves the experimental determination of the flux of Be-7, pp, and CNO solar v(e) and the limit on the effective neutrino magnetic moment using solar neutrinos.
Direct measurement of the Be-7 solar neutrino flux with 192 days of Borexino data
DE BARI, ANTONIO;
2008-01-01
Abstract
We report the direct measurement of the 7 Be solar neutrino signal rate performed with the Borexino detector at the Laboratori Nazionali del Gran Sasso. The interaction rate of the 0.862 MeV Be-7 neutrinos is 49 +/- 3(stat) +/- 4(syst) counts/(day . 100 ton). The hypothesis of no oscillation for Be-7 solar neutrinos is inconsistent with our measurement at the 4 sigma C.L. Our result is the first direct measurement of the survival probability for solar P, in the transition region between matter-enhanced and vacuum-driven oscillations. The measurement improves the experimental determination of the flux of Be-7, pp, and CNO solar v(e) and the limit on the effective neutrino magnetic moment using solar neutrinos.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
