Solar neutrinos

Summary and conclusions

The standard solar model with the standard electroweak theory does not explain the solar neutrino problem. However, a slight modification to this theory, in which there is a mass difference in the neutrinos and mixing between them, does seem to explain the experimental observations. However to test conclusively the theory and oscillation effect, a detector which can detect separately the charged current interactions of the electron neutrinos and neutral current interaction of both the neutrinos with matter and also give accurate measurements of the two interactions is to be built.

The next generation of solar neutrino experiments aims to test the above theory. One experiment, which proposes to detect neutrinos through both neutral and charged current interactions, is the Water Cherenkov Detector of the Sudbury Neutrino Observatory (SNO) at Ontario, Canada. Another Water Cherenkov Detector,the massive Super Kamiokande detector, has just become operational and the analysis of the data being collected from the detector are being reported in many conferences. The scientists at Kamiokande have very recently reported at the Neutrino ’98 Conference the exciting result that the neutrino does have a mass. They are now clear that they have reached a level of understanding in Neutrino Astrophysics, where neutrino oscillation solutions can be discussed.