Study The Inverse Beta Decays In The Daya Bay Neutrino Experiment

The Daya Bay experiment uses the far-near site to measure the reactor neutrino(u-e)and compare the neutrino oscillation parameters to the neutrino case rate(?13)make a preliminary measurement.The experiment detects the neutrino case by countering ? decay(v-e +p? e+ +n)e+ deposits kinetic energy on the order of nanoseconds and forms a prompt signal with e-annihilation;neutrons are captured by hydrogen or gadolinium after slowing down,The capture time on hydrogen and helium is about 200 ?s and 28 ?s,which is called delayed signal.In this paper,we use the experimental data of Daya Bay Experiment 1230 day to analyze the samples of neutron capture on the gadolinium and hydrogen capture,and study the sample and background.and the number of IBD cases observed in the far and near point detectors is about 1.0M and 3.8M,the accidental backgrounds is the largest backgrounds among all kinds of backgrounds,it is about 12%in near sites and 54%in far site.Based on this sample,a preliminary measurement of the neutrino oscillation parameter(013)is performed,and the preliminary measurement result is sin2(2?13)= 0.072± 0.008.