Modeling Compound Nuclear Reactions
with EMPIRE
M. Herman, R. Capote, B. V. Carlson, M. Sin, and A. Trkov
1 Introduction
The description of low-energy nucleon-induced reactions in the continuum region
requires, at the very least, calculations of elastic scattering within the optical model
and of statistical emission of photons and light particles from the compound nucleus
formed from the fusion of the projectile and target. If actinide targets are to be
described, a reasonably sophisticated model of fission should also be included in the
statistical emission calculation. At very low energies, width fluctuation corrections
must be included, while at energies above about 10 MeV, pre-equilibrium effects
should be taken into account.
The EMPIRE code, [36] first released in 1980, calculated both elastic scattering
and the cross sections and spectra of statistical equilibrium and pre-equilibrium
decay processes. It was later extended to include width fluctuation corrections to
low-energy cross sections. A version for heavy-ion induced reactions was also
introduced.
In its second release, EMPIRE-2, the code was entirely rewritten using a modular
structure, as well as taking advantage of more relaxed memory limitations, to obtain
an increase in execution speed of about a factor of 20. The new code was projected
M. Herman
Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
R. Capote · A. Trkov
NAPC-Nuclear Data Section, International Atomic Energy Agency, Vienna, Austria
B. V. Carlson ()
Instituto Tecnológico da Aeronáutica, São José dos Campos, SP, Brazil
M. Sin
Faculty of Physics, University of Bucharest, Bucharest, Romania
© This is a U.S. government work and not under copyright protection
in the U.S.; foreign copyright protection may apply 2021
J. Escher et al. (eds.), Compound-Nuclear Reactions, Springer Proceedings in
Physics 254, https://doi.org/10.1007/978-3-030-58082-7_2
17
with EMPIRE
M. Herman, R. Capote, B. V. Carlson, M. Sin, and A. Trkov
1 Introduction
The description of low-energy nucleon-induced reactions in the continuum region
requires, at the very least, calculations of elastic scattering within the optical model
and of statistical emission of photons and light particles from the compound nucleus
formed from the fusion of the projectile and target. If actinide targets are to be
described, a reasonably sophisticated model of fission should also be included in the
statistical emission calculation. At very low energies, width fluctuation corrections
must be included, while at energies above about 10 MeV, pre-equilibrium effects
should be taken into account.
The EMPIRE code, [36] first released in 1980, calculated both elastic scattering
and the cross sections and spectra of statistical equilibrium and pre-equilibrium
decay processes. It was later extended to include width fluctuation corrections to
low-energy cross sections. A version for heavy-ion induced reactions was also
introduced.
In its second release, EMPIRE-2, the code was entirely rewritten using a modular
structure, as well as taking advantage of more relaxed memory limitations, to obtain
an increase in execution speed of about a factor of 20. The new code was projected
M. Herman
Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
R. Capote · A. Trkov
NAPC-Nuclear Data Section, International Atomic Energy Agency, Vienna, Austria
B. V. Carlson ()
Instituto Tecnológico da Aeronáutica, São José dos Campos, SP, Brazil
M. Sin
Faculty of Physics, University of Bucharest, Bucharest, Romania
© This is a U.S. government work and not under copyright protection
in the U.S.; foreign copyright protection may apply 2021
J. Escher et al. (eds.), Compound-Nuclear Reactions, Springer Proceedings in
Physics 254, https://doi.org/10.1007/978-3-030-58082-7_2
17