Skyshine Line-Beam Response Functions for 20- to 100-MeV Photons

Brockhoff, R.C.; Shultis, J. Kenneth; Faw, R.E.

doi:10.13182/nse96-a24189

Cited by 10 publications

(2 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5) Therefore, it was noted 9) that to calculate the LBRF at a neighboring angle or energy given in tables, an approximate LBRF should be obtained by interpolation between the values of the LBRFs at the tabulated angles or energies, and not interpolation of the fit parameters.…”

Section: S(e )R(e X)mentioning

confidence: 99%

“…Shultis and Faw 8) stated that the four-parameter formula is superior to the threeparameter formula for energies of less than a few MeV; but it does not approximate the LBRF data for energies above 10 MeV as well as the three-parameter formula does. Where the LBRF data for energies above 10 MeV were calculated by Brockhoff et al 9) The values of the fit parameters (a, b, c, and d) in SKYSHINE III were chosen by a least-squares procedure for the logarithmic plot of the LBRF.…”

Section: S(e )R(e X)mentioning

confidence: 99%

See 1 more Smart Citation

Validity of the Four-Parameter Empirical Formula in Approximating the Response Functions for Gamma-ray, Neutron, and Secondary Gamma-ray Skyshine Analyses

Harima

Hirayama

Sakamoto

et al. 2003

Journal of Nuclear Science and Technology

View full text Add to dashboard Cite

A four-parameter approximating formula, R= A e a x b f (x), accurately represents the skyshine line beam response function (LBRF) as a function of the distance (x) of the source-to-detector separation. Here, A is a constant for a given source energy and f (x)=e cx x dx is a damping factor. The four parameters are obtained as follows. (1) The value of parameter a corresponds to that of the LBRF at x=1 meter, which is the result of integrating the basic dose spectrum due to a single scattering particle from an emitted beam for a specified angle and a specified source energy. (2) The value of parameter b corresponds to the slope of a straight line of the response function, log R vs. log x, in the range of small distance from a source, where a single scattering particle dominates. (3) The damping factor ( f (x)) represents the attenuation trend of the LBRF at distances far from the source; the values of parameters c and d control the quantity of attenuation. The necessary reference LBRF data for point mono-directional photon source energies ranging from 0.1 to 10 MeV were generated using the EGS4 Monte Carlo code at 20 emission angles from 0.0 to 180• for 24 source-detector distances up to 2,000 m. The validity of using the four-parameter formula to interpolate the LBRF in the source-todetector distance, in the emitted angle, and in the energy was also ascertained. Furthermore, this formula was applied to the skyshine conical beam response function (CBRF) for a neutron and an associated secondary gamma-ray with the source energy ranged from thermal to 3 GeV. It was ascertained that the CBRF could be accurately approximated by an interpolation of the fitting parameters at an arbitrary distance and emitted cosine angle.

show abstract

Section: S(e )R(e X)mentioning

confidence: 99%

Section: S(e )R(e X)mentioning

confidence: 99%