Program - Brookhaven National Laboratory

GA 3 2:20 PM
Paradigm Shift of Nuclear Model Needs for Future Human Space Missions
Ram Tripathi
NASA Langley Research Center, Hampton, VA 23681, USA
NASA’s new vision looks ahead to future deep space long duration human missions. Protection from the
hazards of severe space radiation for such missions is a grand challenge for the agency. The material
shielding developed for low earth orbit (LEO) human missions has been shown to be inadequate for deep
space human missions. The nuclear models used for designing material shielding are high energy and
pertain to radiation that goes through the shield. But the low energy radiation, and concomitant nuclear
models, those stopped in the material shield were not considered as these did not come inside the spacecraft.
For deep space human missions, from the perspective of human exposures, these low energy radiations (and
nuclear models) significantly contribute to human exposures due to high linear energy transfer (LET) than
the radiation those traverse through and are low LET. We have outlined a detailed plan for such nuclear
model needs and would focus on the current status of these (mostly low energy) cross sections models and
elaborate on future needs and directions. Information contained in this document represents the opinion
of the author(s) only, and does not represent the views or policies of NASA
GA 4 2:40 PM
Overview of the 2011 Release of the Evaluated Nuclear Data Library (ENDL2011)
N. C. Summers, D. A. Brown, B. Beck, M.-A. Descalle, J. E. Escher, R. Hoffman, T. Luu, C. M.
Mattoon, P. Navratil, G. P. A. Nobre, W. E. Ormand, S. Quaglioni, I. J. Thompson, and R. Vogt
Lawrence Livermore National Laboratory, Livermore, CA, USA
R. Barnowski
University of Michigan, Ann Arbor, MI, USA
The Lawrence Livermore National Laboratory (LLNL) Physics Division has produced the next iteration
of LLNL’s evaluated nuclear database, ENDL2011. ENDL2011 is designed to support LLNL’s current and
future nuclear data needs. This library includes 918 distinct transport-ready evaluations in the neutron
sub-library and many physics improvements for energy, nuclear security and stockpile stewardship. In
building this library, we adopted the best of the international nuclear data efforts including the ENDF/B-
VII.0, JENDL, JEFF, and other libraries. This library contains many new evaluations for radiochemical
diagnostics, structural materials, and thermonuclear reactions. We have made an effort to eliminate all
holes in reaction networks, allowing in-line isotopic creation and depletion calculations. We have striven to
keep ENDL2011 at the leading edge of nuclear data library development by reviewing and incorporating
new evaluations as they are made available to the nuclear data community. This release is our most highly
tested release as we have strengthened our already rigorous testing regime by adding tests against IPPE
Activation Ratio Measurements and many more critical assemblies. ENDL2011 is currently being updated
to include the latest ENDF/B-VII.1 release and converted to the new Generalized Nuclear Data (GND)
structure for the next generation of nuclear data formats. This work performed under the auspices of
the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-
07NA27344, and was also supported in part by the National Science Foundation Grant NSF PHY-0555660.
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