First measurement of pp neutrinos in real time in the Borexino detector

by Pablo J. Mosteiro (Princenton University)

Thursday 13 Mar 2014, 16:00 → 17:30 Europe/Rome

Aula Converi (Dip. di Fisica - Edificio G. Marconi)

Neutrinos produced by nuclear reactions in the Sun reach Earth within minutes, providing us with key information about what goes on at the core of our star. Since the first detection of solar neutrinos, an apparent deficit in their detection rate was known as the Solar Neutrino Problem. Today, the Mikheyev-Smirnov-Wolfenstein (MSW) effect is the accepted mechanism by which solar neutrinos oscillate. Several experiments have now demonstrated that solar neutrino oscillations are well described by the Large Mixing Angle (LMA) parameters of the MSW effe! ct. This talk presents progress towards the first real-time measurement of pp neutrinos in the Borexino detector, providing another validation of the LMA-MSW model. The measurement would complete the spectroscopy of pp chain neutrinos in Borexino, thus validating the experiment itself and its previous results. We also report on a measurement of neutrons in a dedicated system within Borexino, which resulted in an improved understanding of neutron rates in liquid scintillator detectors at Gran Sasso depths. This result is crucial to the development of novel direct dark matter detection experiments.