title: A comparison of skyshine computational methods.
abstract: A variety of methods employing radiation transport and point-kernel codes have been used to model two skyshine problems. The first problem is a 1 MeV point source of photons on the surface of the earth inside a 2 m tall and 1 m radius silo having black walls. The skyshine radiation downfield from the point source was estimated with and without a 30-cm-thick concrete lid on the silo. The second benchmark problem is to estimate the skyshine radiation downfield from 12 cylindrical canisters emplaced in a low-level radioactive waste trench. The canisters are filled with ion-exchange resin with a representative radionuclide loading, largely 60Co, 134Cs and 137Cs. The solution methods include use of the MCNP code to solve the problem by directly employing variance reduction techniques, the single-scatter point kernel code GGG-GP, the QADMOD-GP point kernel code, the COHORT Monte Carlo code, the NAC International version of the SKYSHINE-III code, the KSU hybrid method and the associated KSU skyshine codes.
authors.affiliation: Neely Nuclear Research Center, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA. nolan.hertel@me.gatech.edu
authors.forename: Nolan E
authors.initials: NE
authors.lastname: Hertel
authors.forename: Jeremy E
authors.initials: JE
authors.lastname: Sweezy
authors.forename: J Kenneth
authors.initials: JK
authors.lastname: Shultis
authors.forename: J Karl
authors.initials: JK
authors.lastname: Warkentin
authors.forename: Zachary J
authors.initials: ZJ
authors.lastname: Rose
mesh_terms: D000388:Air; D000465:Algorithms; D003198:Computer Simulation; D005720:Gamma Rays; D015233:Models, Statistical; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D011874:Radiometry / Q000379:methods*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D012984:Software; D012986:Software Validation