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The Spm (Stochastic Process Method) Equation for Calculating the Spatial Variation of Neutron Spectra.

AD674610

Publication Date	1960
Personal Author	Klahr, C. N.; Zell, H. J.
Page Count	159
Abstract	The SPM equation is a second order partial differential equation in lethargy (or energy) and spatial coordinates. It promises to describe the slowing down and spatial diffusion of neutrons with sufficient accuracy for shielding problems and for other applications where neutron flux spectra are critical. A primitive SPM with infinite orders of derivatives is first obtained from either the Smoluchowski or Boltzmann equations. It is then truncated after the second order derivatives. The coefficients of two forms of this equation are obtained and suitable boundary conditions are given. A code has been written to solve this equation on the 1103A Univac. Various solutions are given. (Author)
Keywords	Neutron spectrum Stochastic processes Partial differential equations Shielding Neutron flux Inelastic scattering Fission Diffusion Numerical analysis
NTIS Subject Category	46 - Physics 77K - Reactor Physics
Corporate Authors	Control Data Corp Melville N Y TRG Div
Document Type	Technical Report
Title Note	Rept. for May 59-May 60.
NTIS Issue Number	196821
Contract Number	AF 33(616)-5187

The Spm (Stochastic Process Method) Equation for Calculating the Spatial Variation of Neutron Spectra.

The Spm (Stochastic Process Method) Equation for Calculating the Spatial Variation of Neutron Spectra.
AD674610

Publication Date	1960
Personal Author	Klahr, C. N.; Zell, H. J.
Page Count	159
Abstract	The SPM equation is a second order partial differential equation in lethargy (or energy) and spatial coordinates. It promises to describe the slowing down and spatial diffusion of neutrons with sufficient accuracy for shielding problems and for other applications where neutron flux spectra are critical. A primitive SPM with infinite orders of derivatives is first obtained from either the Smoluchowski or Boltzmann equations. It is then truncated after the second order derivatives. The coefficients of two forms of this equation are obtained and suitable boundary conditions are given. A code has been written to solve this equation on the 1103A Univac. Various solutions are given. (Author)
Keywords	Neutron spectrum Stochastic processes Partial differential equations Shielding Neutron flux Inelastic scattering Fission Diffusion Numerical analysis
NTIS Subject Category	46 - Physics 77K - Reactor Physics
Corporate Authors	Control Data Corp Melville N Y TRG Div
Document Type	Technical Report
Title Note	Rept. for May 59-May 60.
NTIS Issue Number	196821
Contract Number	AF 33(616)-5187