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Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Latest News
Valar achieves cold criticality at LANL
Valar Atomics has announced that its Nova Core achieved zero-power criticality on November 17 at Los Alamos National Laboratory’s National Criticality Experiments Research Center (NCERC) at the Nevada National Security Site.
Gene A. Baraff, Raymond L. Murray, A. C. Menius, Jr.
Nuclear Science and Engineering | Volume 4 | Number 5 | November 1958 | Pages 623-634
Technical Paper | doi.org/10.13182/NSE58-A25552
Articles are hosted by Taylor and Francis Online.
Two group perturbation theory of thermal reactors is reviewed and tables of fluxes, adjoint fluxes, arbitrary coefficients, and computation constants are given. A general reactivity formula in matrix notation is derived, and integrals needed in the evaluation of perturbations in the core and reflector are tabulated. The special problem of a reflector void of constant cross-sectional area is also considered.
