${{\mathit p}}{{\mathit e}}{{\mathit p}}$ solar-neutrino flux measured via ${{\mathit \nu}_{{e}}}$ elastic scattering. This process is sensitive to all active neutrino flavors, but with reduced sensitivity to ${{\mathit \nu}_{{\mu}}}$, ${{\mathit \nu}_{{\tau}}}$ due to the cross section difference, $\sigma ({{\mathit \nu}}_{{{\mathit \mu}},{{\mathit \tau}}}{{\mathit e}}$) $\sim{}$ 0.2 ${\mathit \sigma (}$ ${{\mathit \nu}_{{e}}}{{\mathit e}}{)}$. If the ${{\mathit p}}{{\mathit e}}{{\mathit p}}$ solar-neutrino flux involves non-electron flavor active neutrinos, their contribution to the flux is $\sim{}$ 0.2 times that of ${{\mathit \nu}_{{e}}}$.

VALUE ($ 10^{8} $ cm${}^{-2}$s${}^{-1}$) DOCUMENT ID TECN  COMMENT • • We do not use the following data for averages, fits, limits, etc. • • $1.0$ $\pm0.2$ 1 BELLINI 2012 A BORX average flux 1  BELLINI 2012A reports 1.44 MeV ${{\mathit p}}{{\mathit e}}{{\mathit p}}$ solar-neutrino flux measured via ${{\mathit \nu}_{{e}}}$ elastic scattering. The data were collected between January 13, 2008 and May 9, 2010, corresponding to 20,4009 ton$\cdot{}$day fiducial exposure. The listed flux value is calculated from the observed rate of ${{\mathit p}}{{\mathit e}}{{\mathit p}}$ solar neutrino interactions in Borexino ($3.1$ $\pm0.6$ $\pm0.3$ counts/(day$\cdot{}$100 ton)) and the corresponding rate expected for no neutrino flavor oscillations ($4.47$ $\pm0.05$ counts/(day$\cdot{}$100 ton)), using the SSM prediction for the ${{\mathit p}}{{\mathit e}}{{\mathit p}}$ solar neutrino flux of ($14.41$ $\pm0.12$) $ \times 10^{7}$ cm${}^{-2}$s${}^{-1}$.

References:

BELLINI 2012A PRL 108 051302 First Evidence of ${{\mathit p}}{{\mathit e}}{{\mathit p}}$ Solar Neutrinos by Direct Detection in Borexino