Neutral Current Detectors for SNO (The R&D Program at WIPP)

The (Standard) Solar Neutrino Spectrum

Energy Dependent Neutrino Flux Suppression

Matter Induced (MSW) Oscillations

The SNO Detector

The SNO Collaboration

Neutrino Interactions in SNO

Cerenkov Signals & Backgrounds in SNO

Natural Series Decay Schemes

1992 Proposal to Develop NC Detectors for SNO

SNO Cutaway Showing NC Detector Array

Schematic Diagram of SNO NC Detector

He-3 Counters

He(n,p)t Events in 2.5 Atm (He:CH4 = 80:20)

Alpha Contamination in He(n,p)t Window

Depleted U-238 Calibration Spectrum

Photo of Early NC Detector Prototype

1992 Letter to WIPP from LANL

Early NC Detector Construction in Room G

LANL Enclosure in WIPP U/G

Carting Lead in the WIPP U/G

SS Background (Det. No. 3)

Electronics for Prototype Ni CVD

Ni CVD-S-01 Low Gain Channel

Po-210 Rate Drops with Time

Ni CVD-S-02 Low Gain Channel

Ni CVD-S-01 High Gain Channel

Ni CVD-S-02 High Gain Channel (no events)

Fast Neutrons Minimized

SS Detectors - Low Gain Channel

n’s 50 times lower than “rock”

Publication of Results

Contributors

NC Detector Assembly at Univ. of Washington

Assembled ND Detector strings at SNO

Conclusion