Alpha Transport in COG

Technical Report · Wed Jun 04 04:00:00 EDT 2014

DOI:https://doi.org/10.2172/1557049· OSTI ID:1557049

Lent, E. ^[1]

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1. Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)

The following outlines how alpha transport is currently implemented in COG. Alpha transport is handled as a two step process … Step 1: CSDA. Using data and coding borrowed from the AlfaMC code [1], a Continuous Slowing Down Approximation for alphas has been implemented in COG. Following the guide of the AlfaMC code, Gaussian or Landau distributed energy straggling is performed, and a simple Fermi small-angle multiple scattering model is adopted. Since for the energy range under consideration (~1 to 20 MeV), the mean free path for nuclear interactions (e.g., (alpha,neutron), (alpha,gamma), etc.) is very much greater than the range of the alpha, the CSDA approach alone is used to track the alpha. That is nuclear interactions are ignored in this step. Step 2: Nuclear interactions. A fraction (see below) of the CSDA steps are sampled for nuclear reactions – that is, for each step if a random number is less than the fraction, then nuclear reactions are included and any properly weighted secondaries are produced and followed.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC52-07NA27344
• OSTI ID: 1557049
• Report Number(s): LLNL--TR-655365; 775870
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS