The utilization of crisp code in hybrid reactor studies

Abstract

One of the main applications of the Hybrid Reactors (ADS -Accelerator Driven System) is the incineration of transuranics (TRU) by fast neutrons that emerge from a spallation source in a sub critical reactor waste burner [1,2]. For this application, an accurate description and prediction of spallation reaction is necessary, including all the characteristics concerning spatial and energetic angular distributions, spallation products and neutron multiplicity. To describe the nuclear reactions at intermediate and high energies, Monte Carlo calculations have been used. The CRISP package considers the intranuclear cascade (INC) that occurs during the spallation process in a realistic time-sequence approach in which all particles inside the nucleus can participate in the cascade and the nuclear density fluctuations are naturally taken into account during the process. The occupation number of each single particle level is considered as a function of time and a more realistic Pauli blocking mechanism can be performed. None of the existing models have effectively used all those features. The evaporation of protons and alpha particles are taken into account making possible the correct prediction of fissilities of actinides and pre-actinides [3]. Another implementation is the NN single-pion production reaction. This reaction is especially relevant if one is interested in neutron or proton multiplicities, since the creation/emission of pions is directly related with the excitation energy of the residual nucleus. We will present some results obtained with the CRISP package for proton-nucleus reaction at intermediate and high energies. This package was obtained by the coupling of the MCMC [4] and MCEF [5] codes, with the introduction of some improvements, such as better Pauli blocking mechanism, which constrains the residual nucleus energetic evolution to the Pauli Principle from the ground-state to the final compound-nucleus formed at the end of the intranuclear cascade process, and introduction of the most relevant resonant excitation and the NN single pion production channel. The results of interest for ADS development are consistent with the experimental data at different proton energies. More detailed calculations are being performed for studying other features of proton-nucleus reactions and with different targets.

Photon and proton induced fission on heavy nuclei at intermediate energies

“…This code has been developed for more than ten years [8][9][10][11][12][13][14] and it has been applied in the study of fission induced by photons and protons, and for the study of hyper-nuclear decay [15]. It has also been used in the development of new nuclear reactor technologies [16][17][18]. The main feature of this Monte Carlo code is the precise description of the intranuclear cascade, where a time-ordered sequence of collisions is governed by strict verification of the Pauli principle in a square-well nuclear model.…”

Monte Carlo Simulation of Heavy Nuclei Photofission at Intermediate Energies

“…Moreover, there is an increasing interest on fission products due to studies on material damage regarding nuclear reactors [8][9][10], and studies on production of intermediate mass ions source (ISOL) [11][12][13][14][15]. In this work we studied the fission process by using a Monte Carlo simulation performed with the CRISP code.…”

Effects of fissioning nuclei distributions on fragment mass distributions for high energy fission

“…The CRISP code has already been used for evaluating mass distributions of fragments for fission induced by photons at intermediate energies [28], and to calculate spallation yields and neutron multiplicities for reactions induced by high energy protons [29], giving results in good agreement with experimental data. Also, the code has already been used in studies of the ADS (Accelerator Driving System) nuclear-reactors [29][30][31][32]. Recently the CRISP code has been used to study the effects of final state interaction in the decay of hypernuclei [33,34].…”