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DTRA’s advancements in nuclear and radiological detection
A new, more complex nuclear age has begun. Echoing the tensions of the Cold War amid rapidly evolving nuclear and radiological threats, preparedness in the modern age is a contest of scientific innovation. The Research and Development Directorate (RD) at the Defense Threat Reduction Agency (DTRA) is charged with winning this contest.
Esam M. A. Hussein
Nuclear Science and Engineering | Volume 109 | Number 4 | December 1991 | Pages 416-422
Technical Note | doi.org/10.13182/NSE91-A23867
Articles are hosted by Taylor and Francis Online.
Some approximate estimators for obtaining the fluence at a point in Monte Carlo neutron transport calculations are presented and compared with the commonly used next event estimator. These estimators do not require direct evaluation of the scattering probability using Legendre expansions of the differential angular cross sections. The estimators are particularly useful for Monte Carlo programs that sample scattering directions in the center-of-mass coordinate system.