The invention provides a method and a
system for simulating and predicting the intensity of a slow
positron source in a
research reactor. The method comprises the following steps: S1, reading arrangement information of components in a reactor core of the
research reactor; s2, constructing a
research reactor core Monte Carlo model containing a slow
positron source device, and obtaining
neutron multi-group angle flux and
photon multi-group angle flux information near a slow
positron source generation device; s3, constructing a slow positron source Monte Carlo model; s4, performing energy and angle double sampling to obtain incident
neutron energy probability
density distribution functions fn, ig and ia, angle probability
density distribution functions fn and ia, incident
photon flux energy probability
density distribution functions fg, ig and ia, angle probability density distribution functions fg and ia and
neutron and
photon weight factors; s5, function sampling of particle types, energy and angles is carried out; and S6, acquiring slow positron distribution information generated in the slow positron generation device. According to the method, the generation of the slow positron and the
full life cycle of transportation are accurately considered through multi-stage
coupling, and accurate prediction of the intensity of the slow positron source is realized.