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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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DNFSB’s Summers ends board tenure, extending agency’s loss of quorum
Lee
Summers
The Defense Nuclear Facilities Safety Board, the independent agency responsible for ensuring that Department of Energy facilities are protective of public health and safety, announced that the board’s acting chairman, Thomas Summers, has concluded his service with the agency, having completed his second term as a board member on October 18.
Summers’ departure leaves Patricia Lee, who joined the DNFSB after being confirmed by the Senate in July 2024, as the board’s only remaining member and acting chair. Lee’s DNFSB board term ends in October 2027.
W. Seifritz
Nuclear Technology | Volume 7 | Number 6 | December 1969 | Pages 513-522
Reactor | doi.org/10.13182/NT69-A28370
Articles are hosted by Taylor and Francis Online.
A newly developed special two-detector cross-correlation experiment of zero-power reactor-noise analysis is applied to determining characteristic kinetic-reactor parameters. This method-called polarity correlation in the frequency domain-is based on the detailed analysis of the stochastic Coherence Function, in contrast to the analysis of auto and/or cross power spectral density functions. The coherence function is easily obtained by polarity correlation of two filtered random-neutron-noise signals simultaneously sampled in a reactor system using neutronsensitive detectors in the current mode of operation. The advantage and the progress in using this technique is both its simplicity and the automatic elimination of the equipment frequency response, which is of special importance when analyzing fast-reactor-noise spectra. A series of prompt-neutron-decay constant measurements was performed on several configurations of the STARK and SNEAK facilities. Moreover, special attention and effort is dedicated to reactivity shutdown measurements by the polarity correlation method. An on-line reactivity meter is described which is particularly suited to making reactivity measurements in large plutonium fueled reactors. Shutdown reactivity measurements were performed down to -8 dollars.