Accession Number : AD0663563

Title :   NEUTRON AND GAMMA-RAY STREAMING THROUGH A TWO-LEGGED, THICK-WALL STEEL DUCT,

Descriptive Note : Technical rept. Jan-Jun 67,

Corporate Author : NAVAL CIVIL ENGINEERING LAB PORT HUENEME CALIF

Personal Author(s) : Gardner,L. B.

Report Date : JAN 1968

Pagination or Media Count : 25

Abstract : The purpose of the study was to determine the validity of simplified formulas for calculating the protection against streaming neutrons and gamma rays afforded by thick-wall steel ducts. The report summarizes the results of neutron and gamma-ray dose calculations by albedo techniques and the results of gamma-ray dose measurements performed for a two-legged, thick-wall steel duct. Original data are presented for (1) the Monte Carlo calculation of neutron and gamma-ray streaming; (2) survey meter measurement of neutron dose; (3) the measurement of neutron energy spectra by foil activation techniques and subsequent calculation of dose; and (4) the measurement of prompt gamma rays by a liquid scintillation detector and by pulse shape discrimination. The dose normalized to the dose at 1 centimeter in free air is a common parameter, allowing the intercomparison of the different experimental and theoretical results. The work varifies the semiemperical formulas of Song and Chapman for the calculation of normalized dose rates resulting from neutrons and gamma rays streaming through thick-wall steel ducts. It is also shown that 05R/STATEST and OGRE-G computer codes are considerably more precise than the ADONIS code for the same use of computer time. Concrete ducts are seen to offer slightly more protection than thick-wall steel ducts. (Author)

Descriptors :   (*FALLOUT SHELTERS, *DUCTS), (*SHIELDING, DUCTS), GAMMA RAYS, NEUTRONS, ALBEDO, STEEL, DOSE RATE, MONTE CARLO METHOD, NEUTRON SPECTRUM, NEUTRON ACTIVATION, SCINTILLATION COUNTERS, COMPUTER PROGRAMS

Subject Categories : Nuclear Radiation Shield, Protection & Safety

Distribution Statement : APPROVED FOR PUBLIC RELEASE