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This paper provides a technical description of the SuperNova Early Warning System (SNEWS), an international network of experiments with the goal of providing an early warning of a galactic supernova.

Results are reported from a joint analysis of Phase I and Phase II data from the Sudbury Neutrino Observatory. The effective electron kinetic energy threshold used is T eff = 3.5 MeV, the lowest analysis threshold yet achieved with water Cherenkov detector data. In units of 10 6 cm −2 s −1 , the total flux of active-flavor neutrinos from 8 B decay in the Sun measured using the neutral current (NC) reaction of neutrinos on deuterons, with no constraint on the 8 B neutrino energy spectrum, is found to be NC = 5.140 +0.160 −0.158 (stat) +0.132 −0.117 (syst). These uncertainties are more than a factor of 2 smaller than previously published results. Also presented are the spectra of recoil electrons from the charged current reaction of neutrinos on deuterons and the elastic scattering of electrons. A fit to the Sudbury Neutrino Observatory data in which the free parameters directly describe the total 8 B neutrino flux and the energy-dependent ν e survival probability provides a measure of the total 8

Results are reported from the complete salt phase of the Sudbury Neutrino Observatory experiment in which NaCl was dissolved in the D 2 O target. The addition of salt enhanced the signal from neutron capture, as compared to the pure D 2 O detector. By making a statistical separation of charged-current events from other types based on event-isotropy criteria, the effective electron recoil energy spectrum has been extracted. In units of 10 6 cm −2 s −1 , the total flux of active-flavor neutrinos from 8 B decay in the Sun is found to be 4.94

The Sudbury Neutrino Observatory (SNO) used an array of 3 He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (ν x ) 8 B solar neutrino flux. This technique is independent of previous methods employed by SNO The Sudbury Neutrino Observatory [1] detects 8 B solar neutrinos through three reactions: charged-current interactions (CC) on deuterons, in which only electron neutrinos participate; neutrino-electron elastic scattering (ES), which are dominated by contributions from electron neutrinos; and neutral-current (NC) disintegration of the deuteron by neutri-

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The Sudbury Neutrino Observatory (SNO) has precisely determined the total active (ν x ) 8 B solar neutrino flux without assumptions about the energy dependence of the ν e survival probability. The measurements were made with dissolved NaCl in the heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 ± 0.27 (stat) ± 0.38 (syst) × 10 6 cm −2 s −1 , in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields ∆m 2 = 7.1 +1.2 −0.6 × 10 −5 eV 2 and θ = 32.5 +2. ES).Only electron neutrinos produce charged-current interactions (CC), while the neutral-current (NC) and elastic scattering (ES) reactions have sensitivity to non-electron flavors. The NC reaction measures the total flux of all active neutrino flavors above a threshold of 2.2 MeV. SNO previously measured the NC rate by observing neutron captures on deuterons, and found that a Standard-Model description with an undistorted 8 B neutrino spectrum and CC, ES, and NC rates due solely to ν e interactions was rejected [2, 3]. This Letter presents measurements of the CC, NC, and ES rates from SNO's dissolved salt phase.The addition of 2 tonnes of NaCl to the kilotonne of heavy water increased the neutron capture efficiency and the associated Cherenkov light. The solution was thoroughly mixed and

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. E1-and E2-S of 12 alpha,gamma 0 16 O from gamma-ray angular distributions with a 4pi detector array