Absence of a day-night asymmetry in the 7Be solar neutrino rate in Borexino

Loading...
Thumbnail Image
Publication date
2012
Reading date
Journal Title
Journal ISSN
Volume Title
Publisher
Metrics
Export
Abstract
We report on a search for the day-night asymmetry of the Be-7 solar neutrino rate measured by Borexino at the Laboratori Nazionali del Gran Sasso (LNGS), Italy. The measured value, Adn=0.001 +- 0.012 (stat) +- 0.007 (syst), shows the absence of a significant asymmetry. This result alone rejects the so-called LOW solution at more than 8.5 sigma. Combined with the other solar neutrino data, it isolates the Large Mixing Angle (LMA) -- MSW solution at DeltaChi2 > 190 without relying on the assumption of CPT symmetry in the neutrino sector. We also show that including the day-night asymmetry, data from Borexino alone restricts the MSW neutrino oscillations to the LMA solution at 90% confidence level.
Description
Keywords
Bibliographic reference
Borexino Collaboration Bellini, Gianpaolo Peña Garay, Carlos 2012 Absence of a day-night asymmetry in the 7Be solar neutrino rate in Borexino Physics Letters B 707 1 22 26
Collections