11 research outputs found
Measurement of the response of a gallium metal solar neutrino experiment to neutrinos from a 51Cr source
The neutrino capture rate measured by the Russian-American Gallium Experiment
is well below that predicted by solar models. To check the response of this
experiment to low-energy neutrinos, a 517 kCi source of 51Cr was produced by
irradiating 512.7 g of 92.4%-enriched 50Cr in a high-flux fast neutron reactor.
This source, which mainly emits monoenergetic 747-keV neutrinos, was placed at
the center of a 13.1 tonne target of liquid gallium and the cross section for
the production of 71Ge by the inverse beta decay reaction was measured to be
(5.55 +/- 0.60 (stat.) +/- 0.32 (syst.)) x 10^(-45) cm^2. The ratio of this
cross section to the theoretical cross section of Bahcall for this reaction is
0.95 +/- 0.12 (exp.) +/- 0.03 (theor.) and to the cross section of Haxton is
0.87 +/- 0.11 (exp.) +/- 0.09 (theor.).
This good agreement between prediction and observation implies that the
overall experimental efficiency for the solar neutrino measurements is
correctly determined and provides considerable evidence for the reliability of
the solar neutrino measurement.Comment: 20 pages including figures in two column forma