arXiv subjects

SNO Collaboration

Publications and source records attributed to SNO Collaboration.

21 records · Page 2Linked to original sources

arXiv2002

Direct Evidence for Neutrino Flavor Transformation from Neutral-Current Interactions in the Sudbury Neutrino Observatory

Observations of neutral current neutrino interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using the neutral current, elastic scattering, and charged current reactions and assuming the standard 8B shape, the electron-neutrino component of the 8B solar flux is 1.76 +/-0.05(stat.)+/-0.09(syst.) x10^6/(cm^2 s), for a kinetic energy threshold of 5 MeV. The non-electron neutrino component is 3.41+/-0.45(stat.)+0.48,-0.45(syst.) x10^6/(cm^2 s), 5.3 standard deviations greater than zero, providing strong evidence for solar electron neutrino flavor transformation. The total flux measured with the NC reaction is 5.09 +0.44,-0.43(stat.)+0.46,-0.43(syst.)x10^6/(cm^2 s), consistent with solar models.

nucl-ex↗

arXiv2001

Solar Neutrino Results from the Sudbury Neutrino Observatory

We describe here the measurement of the flux of neutrinos created by the decay of solar ^8B by the Sudbury Neutrino Observatory (SNO). The neutrinos were detected via the charged current (CC) reaction on deuterium and by the elastic scattering (ES) of electrons. The CC reaction is sensitive exclusively to $ν_e$'s, while the ES reaction also has a small sensitivity to $ν_μ$'s and $ν_τ$'s. The flux of $ν_e$'s from ^8B decay measured by the CC reaction rate is $ϕ^CC (ν_e) = 1.75 \pm 0.07 (stat.)^{+0.1 2}_{-0.11} (sys.) \pm 0.05 (theor.) \times 10^6 cm^-2 s^-1$. Assuming no flavor transformation, the flux inferred from the ES reaction rate is $ϕ^ES (ν_x)=2.39\pm 0.34 (stat.) ^{+0.16}_{-0.14} (sys.) \times 10^6 cm^-2 s^-1$. Comparison of $ϕ^CC (ν_e)$ to the Super-Kamiokande Collaboration's precision value of $ϕ^ES (ν_x)$ yields a $3.3σ$ difference, assuming the systematic uncertainties are normally distributed, providing evidence that there is a non-electron flavor active neutrino component in the solar flux. The total flux of active ^8B neutrinos is thus determined to be $5.44\pm 0.99 \times 10^6 cm^-2 s^-1$, in close agreement with the predictions of solar models.

hep-ex↗

arXiv2001

Measurement of the rate of nu_e + d --> p + p + e^- interactions produced by 8B solar neutrinos at the Sudbury Neutrino Observatory

Solar neutrinos from the decay of $^8$B have been detected at the Sudbury Neutrino Observatory (SNO) via the charged current (CC) reaction on deuterium and by the elastic scattering (ES) of electrons. The CC reaction is sensitive exclusively to nu_e's, while the ES reaction also has a small sensitivity to nu_mu's and nu_tau's. The flux of nu_e's from ^8B decay measured by the CC reaction rate is ϕ^CC(nu_e) = 1.75 +/- 0.07 (stat)+0.12/-0.11 (sys.) +/- 0.05(theor) x 10^6 /cm^2 s. Assuming no flavor transformation, the flux inferred from the ES reaction rate is ϕ^ES(nu_x) = 2.39+/-0.34 (stat.)+0.16}/-0.14 (sys) x 10^6 /cm^2 s. Comparison of ϕ^CC(nu_e) to the Super-Kamiokande Collaboration's precision value of ϕ^ES(ν_x) yields a 3.3 sigma difference, providing evidence that there is a non-electron flavor active neutrino component in the solar flux. The total flux of active ^8B neutrinos is thus determined to be 5.44 +/-0.99 x 10^6/cm^2 s, in close agreement with the predictions of solar models.

nucl-ex↗