Integral Fluxes, Day-Night, and Spectrum Results from SNO's 391-Day Salt Phase

TL;DR

This paper reports on the measurements of solar neutrino fluxes, spectrum, and day-night asymmetries from the SNO detector during its salt phase, providing insights into neutrino properties and solar physics.

Contribution

It presents new measurements of neutrino fluxes, spectrum, and asymmetries using salt-enhanced detection, improving differentiation of neutral current events.

Findings

Neutral current flux measurements confirm solar neutrino flux.

Electron spectrum matches undistorted solar 8B neutrino spectrum.

Detected day-night asymmetries in neutrino fluxes.

Abstract

The Sudbury Neutrino Observatory is a 1000t heavy water Cherenkov detector observing neutrinos from the Sun and other astrophysical sources. Measurements of the integral solar neutrino fluxes of charged current, neutral current and elastic scattering events are reported for 391 days of live data from the salt phase of SNO operation. In this phase 2t of salt were dissolved in the heavy water, which enhanced and differentiated the detection of neutral current events. Day-night asymmetries in these fluxes were also determined. The measured electron spectrum from the charged-current channel is compatible with the undistorted spectrum of the solar 8B neutrino flux.