skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Pion physics in the Liege intranuclear cascade model

Abstract

The implementation of {pi} production in the Liege intranuclear cascade model (INCL4) for spallation reactions is revisited to alleviate the overestimate of the {pi} yield. Three modifications are proposed for this purpose: a better {pi}N cross section at high energy, the introduction of a {pi} average potential, and the modification of the average mass of the {delta} resonance. The {pi} potential is determined from a global fit of a set of data bearing on {pi} production in proton-induced reactions, on {pi}-nucleus and absorption cross sections, and on proton production in {pi}-induced reactions. The resulting {pi} potential is poorly determined in the nuclear interior and agrees with the phenomenological optical-model potentials in the surface region. With these modifications, the predictions of the INCL4 model concerning {pi} production cross sections in proton-induced reactions are considerably improved. Predictions of the improved version for {pi}-nucleus reaction and absorption cross sections and for proton, residue, and fission cross sections in {pi}-induced reactions are also presented and shown to give reasonably good agreement. Neutron production and some aspects of fission in {pi}-induced reactions are also investigated and reasonably well predicted. Effects on the modifications on observables, which are not directly linked with {pi}'s, such as themore » neutron yield and the residue mass and charge spectra in proton-induced reactions are also investigated and shown to improve the description of these observable quantities. Several results on {pi} production and the relative insentivity to the {pi} potential in the nuclear interior are shown to be consistent with the fact that most {pi}'s are not produced in early collisions. Importance of rescattering in {pi} absorption on nuclei is also pointed out. A comparison is made with the so-called {delta}-hole model. Residual discrepancies are identified and are interpreted as due to the lack of {pi} interaction with two nucleons at low energy, to the neglect of quantum motion effects, and to a possible underestimate of rescattering.« less

Authors:
 [1];  [2];  [3]
  1. SCK-CEN, Boeretang 200, B-2400 Mol (Belgium)
  2. (Belgium)
  3. University of Liege, Physics Department, allee du 6 Aou circumflex t 17, bat. B5, B-4000 Liege 1 (Belgium)
Publication Date:
OSTI Identifier:
20864212
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 74; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevC.74.064607; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ABSORPTION; CROSS SECTIONS; FISSION; NEUTRONS; NUCLEAR CASCADES; NUCLEAR REACTION YIELD; NUCLEI; OPTICAL MODELS; PARTICLE-HOLE MODEL; PIONS; POTENTIALS; PROTON REACTIONS; PROTONS; RESCATTERING; RESONANCE; SPALLATION

Citation Formats

Aoust, Th., University of Liege, Physics Department, allee du 6 Aou circumflex t 17, bat. B5, B-4000 Liege 1, and Cugnon, J.. Pion physics in the Liege intranuclear cascade model. United States: N. p., 2006. Web. doi:10.1103/PHYSREVC.74.064607.
Aoust, Th., University of Liege, Physics Department, allee du 6 Aou circumflex t 17, bat. B5, B-4000 Liege 1, & Cugnon, J.. Pion physics in the Liege intranuclear cascade model. United States. doi:10.1103/PHYSREVC.74.064607.
Aoust, Th., University of Liege, Physics Department, allee du 6 Aou circumflex t 17, bat. B5, B-4000 Liege 1, and Cugnon, J.. Fri . "Pion physics in the Liege intranuclear cascade model". United States. doi:10.1103/PHYSREVC.74.064607.
@article{osti_20864212,
title = {Pion physics in the Liege intranuclear cascade model},
author = {Aoust, Th. and University of Liege, Physics Department, allee du 6 Aou circumflex t 17, bat. B5, B-4000 Liege 1 and Cugnon, J.},
abstractNote = {The implementation of {pi} production in the Liege intranuclear cascade model (INCL4) for spallation reactions is revisited to alleviate the overestimate of the {pi} yield. Three modifications are proposed for this purpose: a better {pi}N cross section at high energy, the introduction of a {pi} average potential, and the modification of the average mass of the {delta} resonance. The {pi} potential is determined from a global fit of a set of data bearing on {pi} production in proton-induced reactions, on {pi}-nucleus and absorption cross sections, and on proton production in {pi}-induced reactions. The resulting {pi} potential is poorly determined in the nuclear interior and agrees with the phenomenological optical-model potentials in the surface region. With these modifications, the predictions of the INCL4 model concerning {pi} production cross sections in proton-induced reactions are considerably improved. Predictions of the improved version for {pi}-nucleus reaction and absorption cross sections and for proton, residue, and fission cross sections in {pi}-induced reactions are also presented and shown to give reasonably good agreement. Neutron production and some aspects of fission in {pi}-induced reactions are also investigated and reasonably well predicted. Effects on the modifications on observables, which are not directly linked with {pi}'s, such as the neutron yield and the residue mass and charge spectra in proton-induced reactions are also investigated and shown to improve the description of these observable quantities. Several results on {pi} production and the relative insentivity to the {pi} potential in the nuclear interior are shown to be consistent with the fact that most {pi}'s are not produced in early collisions. Importance of rescattering in {pi} absorption on nuclei is also pointed out. A comparison is made with the so-called {delta}-hole model. Residual discrepancies are identified and are interpreted as due to the lack of {pi} interaction with two nucleons at low energy, to the neglect of quantum motion effects, and to a possible underestimate of rescattering.},
doi = {10.1103/PHYSREVC.74.064607},
journal = {Physical Review. C, Nuclear Physics},
number = 6,
volume = 74,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}