Measurement of the response of a Ga solar neutrino experiment to neutrinos from a Ar37 source
/ Authors
J. N. Abdurashitov, V. I. Barsanov, T. J. Bowles, B. Cleveland, S. Elliott, V. Gavrin, S. V. Girin, V. Gorbachev, P. P. Gurkina, W. Haxton
and 35 more authors
T. Ibragimova, A. Janelidze, A. Kalikhov, A. Karpenko, N. G. Khairnasov, Yu. S. Khomyakov, T. Knodel, A. V. Korenkova, N. Kotelnikov, K. Lande, V. Maltsev, S. Markov, V. Matveev, I. Mirmov, O. Mishin, J. Nico, N. Oshkanov, V. M. Poplavsky, A. Petrov, V. Popov, V. Selin, Z. N. Shakirov, A. Shikhin, A. Suzuki, W. Teasdale, A. M. Tuchkov, B. A. Vasiliev, E. Veretenkin, V. M. Vermul, S. Voronov, J. Wilkerson, V. Yants, A. Zamyatina, G. Zatsepin, S. B. Zlokazov
/ Abstract
An intense source of {sup 37}Ar was produced by the (n,{alpha}) reaction on {sup 40}Ca by irradiating 330 kg of calcium oxide in the fast neutron breeder reactor at Zarechny, Russia. The {sup 37}Ar was released from the solid target by dissolution in acid, collected from this solution, purified, sealed into a small source, and brought to the Baksan Neutrino Observatory where it was used to irradiate 13 tonnes of gallium metal in the Russian-American gallium solar neutrino experiment SAGE. Ten exposures of the gallium to the source, whose initial strength was 409{+-}2kCi, were carried out during the period April to September 2004. The {sup 71}Ge produced by the reaction {sup 71}Ga({nu}{sub e},e{sup -}){sup 71}Ge was extracted, purified, and counted. The measured production rate was 11.0{sub -0.9}{sup +1.0} (stat){+-}0.6 (syst) atoms of {sup 71}Ge/d, which is 0.79{sub -0.10}{sup +0.09} of the theoretically calculated production rate. When all neutrino source experiments with gallium are considered together, there is an indication the theoretical cross section has been overestimated.
Journal: Physical Review C