Program - Brookhaven National Laboratory

atios) is performed. In relation to this, a CASMO analysis is repeated using for the most relevant nuclides,
decay data taken from the ORIGEN library. Thereby, the impact of these specific data versus other sources
of differences, including numerical methods as well as other nuclear data, is isolated and quantified. As
a last step, for the same nuclides, a review and comparison of decay data is conducted for a wide range
of libraries, and from this, uncertainty ranges are estimated. These uncertainties are then propagated
through stochastic sampling in CASMO-5M decay calculations. On this basis, the level of uncertainty in
predicted heat load/activities is quantified and discussed in relation to the identified main contributors
and associated uncertainty ranges.
PE 8 5:45 PM
Preequilibrium Emission of Light Fragments in Spallation Reactions
Leslie M. Kerby, Stepan G. Mashnik, Arnold J. Sierk
Los Alamos National Laboratory, Los Alamos, NM 87545, USA
Emission of light fragments (LF) from various nuclear reactions is a scientifically interesting and open
question. Different reaction mechanisms contribute to their production; the relative roles of each, and
how they change with incident energy, mass number of the target, and the type and emission energy of
the fragments is not completely understood. None of the available models are able to accurately predict
emission of LF from arbitrary reactions. However, the ability to describe production of LF (especially
at intermediate and high energies) from many reactions is important for different applications, such as
cosmic-ray-induced Single Event Upsets (SEU), radiation protection, and cancer therapy with proton and
heavy-ion beams, to name just a few. The CEM03.03 and LAQGSM03.03 event generators in MCNP6
describe quite well the spectra of fragments with sizes up to 4 He across a broad range of target masses and
incident energies (up to ∼ 5 GeV for CEM and up to ∼ 1 TeV/A for LAQGSM). However, they do not
predict well the high-energy tails of LF heavier than 4 He. Most LF with energies above several tens of MeV
are emitted during the preequilibrium stage of a reaction. The current versions of the CEM and LAQGSM
event generators do not account for preequilibrium emission of LF larger than 4 He. The aim of our work is
to extend the preequilibrium model in them to include such processes, leading to an increase of predictive
power of LF-production in MCNP6. Extending our models to include emission of fragments heavier than
4 He at the preequilibrium stage provides much better agreement with experimental data. Recent data
measured by Hagiwara et al. at the National Institute of Radiological Science (NIRS) of Japan and by
Goldenbaum et al. (the Proton Induced SpAllation (PISA) collaboration) at COSY (COoler SYnchrotron)
of the Jülich Research Center are analyzed and compared with our results.
Session PF Nuclear Physics Education
Thursday March 7, 2013
Room: Central Park East at 3:30 PM
PF 1 3:30 PM
The Stewardship Science Academic Alliance: A Model of Education for Fundamental and
Applied Low-Energy Nuclear Science
Jolie A. Cizewski
Rutgers University, New Brunswick, NJ USA
242