Measurement of the total cross section for the nu-bar/sub e/+p→n+e+ reaction by recording neutrons in the reactor at the Rovno Nuclear Power Plant

A detector for the nu-bar/sub e/+p→n+e+ reaction recording neutrons from this reaction has been modified in the neutrino laboratory at the Rovno Nuclear Power Plant. The counting rate has risen to 370 neutrino events per 105 sec, the ratio of the effect to the background has been improved, and the detection efficiency determined with better accuracy. The reaction cross section has been measured for the antineutrino spectrum of the VVER-440 reactor and found to be equal to sigma-bar/sub f/ = 5.71 x 10-43 cm2/fission +- 3% (reactor) +- 6% (detector). The cross section of the reaction per single fission of 235U is found to be sigma/sup(5)/sub f/ = 5.97 x 10-43 cm2/fission +- 3.5% (reactor) +- 6% (detector). The results obtained by us are compared with the calculated cross section for inverse β-decay and results of other experiments