Application of the Variational Method to the Calculation of the Time Dependence of the Neutron Flux in Small Pulsed Slabs, Cylinders and Spheres (open access)

Application of the Variational Method to the Calculation of the Time Dependence of the Neutron Flux in Small Pulsed Slabs, Cylinders and Spheres

The variational method is applied to the monoenergetic time dependent transport equation to obtain a simple relation for the asymptotic decay constant in small pulsed assemblies. The results indicate that flat trial functions may be a reasonable representation of the flux distributions in the thin slab limit. This approach is superior to many of the usual transport approximations.
Date: December 16, 1963
Creator: Judge, F. D. & Daitch, Paul B. (Paul Bernard), 1925-
System: The UNT Digital Library
Evaluation of Resonance Capture Approximations (open access)

Evaluation of Resonance Capture Approximations

The program KRUDE, which solves the slowing down and adjoint equations for a mixture of resonance and nonresonance isotopes in an infinite homogeneous medium, was used to evaluate some resonance capture approximations (variational and successive) that use linear combinations of narrow and wide resonance fluxes. Results obtained for resonance capture in the 291-ev resonance of Zr/sup 91/ and the 192-ev resonance of U/sup 238/ are compared, and three methods for including Doppler effects in the variational method are considered.
Date: December 16, 1963
Creator: Edgar, K. R.
System: The UNT Digital Library
[Delta]I = 1/2 Rule for Non-Leptonic Strangeness-Changing Decay Processes (open access)

[Delta]I = 1/2 Rule for Non-Leptonic Strangeness-Changing Decay Processes

Gell-Mann and Pais were the first to suggest that the non-leptonic decay processes of strange particles may be subject to an isospin selection rule, allowing only those decay transitions which involve a change [delta]I = 1/2 in to total isopin of the system. At present, however, there is really no theoretical framework for the description of weak interactions into which this selection rule fits in a natural and compelling way. The report includes sections on the 91) decay processes of the [caret] hyperon, (2) decay processes, (3) [complex conjugate] decay processes, and (6) K[pi]3 decay processes. We have considered the evidence on all of the known non-leeptonic non-radiative decay modes of strange particles. All of this evidence is in good qualitative accord with the [delta]I = 1/2 selection rule.
Date: December 2, 1963
Creator: Dalitz, R. H. (Richard Henry), 1925-2006.
System: The UNT Digital Library