A radiochemical 71Ga-71Ge experiment to determine the primary flux of neutrinos from the Sun began measurements of the solar neutrino flux at the Baksan Neutrino Observatory in 1990. The number of 71Ge atoms extracted from 30 tons of gallium in 1990 and 57 tons in 1991 was measured in twelve runs during the period of January 1990 to December 1991. For the 1990 data, we observed the capture rate to be 20 + 15 -20 (stat) ± 32 (syst) SNU, resulting in a limit of less than 79 SNU (90% CL). This is to be compared with 132 SNU predicted by the Standard Solar Model. The 1991 data, taken with 57 tons of gallium, shows a non zero 71Ge signal. A final result from the 1990 and 1991 data is still pending completion of studies of possible systematic effects. © 1993.
Publication Source (Journal or Book title)
Nuclear Physics B (Proceedings Supplements)
Anosov, O., Faizov, E., Gavrin, V., Kalikhov, A., Knodel, T., Knyshenko, I., Kornoukhov, V., Mirmov, I., Ostrinsky, A., Pshukov, A., Shikhin, A., Timofeyev, P., Veretenkin, E., Vermul, V., Zatsepin, G., Bowles, T., Elliott, S., Nico, J., O'Brien, H., Wark, D., Wilkerson, J., Cleveland, B., Davis, R., Lande, K., Cherry, M., & Kouzes, R. (1993). Results from the Soviet-American gallium experiment. Nuclear Physics B (Proceedings Supplements), 31 (C), 111-116. https://doi.org/10.1016/0920-5632(93)90121-L