A new approximating model for gamma-ray buildup factors of stratified shields

Journal Article · Sat Oct 01 00:00:00 EDT 1994 · Nuclear Science and Engineering; (United States)

OSTI ID:6847724

Shin, K ^[1]; Hirayama, H ^[2]

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1. Kyoto Univ. (Japan). Dept. of Nuclear Engineering
2. National Lab. for High Energy Physics, Ibaraki (Japan)

A new approximate expression for gamma-ray buildup factors of multilayered shields is proposed. The expression is formulated based on the vector form and considers the gamma-ray energy spectrum directly. It treats the gamma-ray transmission by a transmission matrix and the backscattering by an albedo matrix. Its capability of reproducing the buildup factors for multilayered shields is demonstrate by using double-layered shields composed of two materials of water, iron, and lead at 1 and 10 MeV. The data of three-layered shields of these materials are also very well reproduced. The mechanism of the density effect arising, which appears in the buildup factor for a point isotropic source, is clearly interpreted by the current method to be a geometrical effect. A correction factor for incorporating the density effect into the current expression is derived. The modified expression is successfully applied to buildup factors for a 0.5-MeV point isotropic source for two-layered shields of water and iron.

• OSTI ID: 6847724
• Journal Information: Nuclear Science and Engineering; (United States), Journal Name: Nuclear Science and Engineering; (United States) Vol. 118:2; ISSN NSENAO; ISSN 0029-5639
• Country of Publication: United States
• Language: English

Related Subjects

663620* -- Physics of Radiations Other Than Neutrons-- (1992-)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BUILDUP
COMPOSITE MATERIALS
ELECTROMAGNETIC RADIATION
ELEMENTS
GAMMA RADIATION
HYDROGEN COMPOUNDS
IONIZING RADIATIONS
IRON
KERNELS
MATERIALS
METALS
NEUTRAL-PARTICLE TRANSPORT
OXYGEN COMPOUNDS
PHOTON TRANSPORT
POINT KERNELS
RADIATION TRANSPORT
RADIATIONS
SHIELDS
TRANSITION ELEMENTS
WATER