An enhanced geometry-independent mesh weight window generator for MCNP Metadata

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  • Main Title An enhanced geometry-independent mesh weight window generator for MCNP


  • Author: Evans, T.M.
    Creator Type: Personal
  • Author: Hendricks, J.S.
    Creator Type: Personal


  • Sponsor: United States. Department of Energy.
    Contributor Type: Organization
    Contributor Info: USDOE, Washington, DC (United States)


  • Name: Los Alamos National Laboratory
    Place of Publication: New Mexico
    Additional Info: Los Alamos National Lab., NM (United States)


  • Creation: 1997-12-31


  • English


  • Content Description: A new, enhanced, weight window generator suite has been developed for MCNP{trademark}. The new generator correctly estimates importances in either an user-specified, geometry-independent orthogonal grid or in MCNP geometric cells. The geometry-independent option alleviates the need to subdivide the MCNP cell geometry for variance reduction purposes. In addition, the new suite corrects several pathologies in the existing MCNP weight window generator. To verify the correctness of the new implementation, comparisons are performed with the analytical solution for the cell importance. Using the new generator, differences between Monte Carlo generated and analytical importances are less than 0.1%. Also, assumptions implicit in the original MCNP generator are shown to be poor in problems with high scattering media. The new generator is fully compatible with MCNP`s AVATAR{trademark} automatic variance reduction method. The new generator applications, together with AVATAR, gives MCNP an enhanced suite of variance reduction methods. The flexibility and efficacy of this suite is demonstrated in a neutron porosity tool well-logging problem.
  • Physical Description: 9 p.


  • Keyword: Modifications
  • Keyword: Adjoint Difference Method
  • Keyword: Neutron Logging
  • Keyword: Analytical Solution
  • STI Subject Categories: 99 Mathematics, Computers, Information Science, Management, Law, Miscellaneous
  • Keyword: Neutron Transport
  • STI Subject Categories: 66 Physics
  • Keyword: Mesh Generation
  • Keyword: Comparative Evaluations
  • Keyword: A Codes
  • STI Subject Categories: 44 Instrumentation, Including Nuclear And Particle Detectors
  • Keyword: Accuracy
  • Keyword: M Codes


  • Conference: Radiation protection and shielding topical meeting: technologies for the new century, Nashville, TN (United States), 19-23 Apr 1998


  • Name: Office of Scientific & Technical Information Technical Reports
    Code: OSTI


  • Name: UNT Libraries Government Documents Department
    Code: UNTGD

Resource Type

  • Article


  • Text


  • Other: DE98004373
  • Report No.: LA-UR--97-5057
  • Report No.: CONF-980403--
  • Grant Number: W-7405-ENG-36
  • Office of Scientific & Technical Information Report Number: 663177
  • Archival Resource Key: ark:/67531/metadc711752


  • Display Note: INIS; OSTI as DE98004373