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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Remembering ANS member Gil Brown
Brown
The nuclear community is mourning the loss of Gilbert Brown, who passed away on July 11 at the age of 77 following a battle with cancer.
Brown, an American Nuclear Society Fellow and an ANS member for nearly 50 years, joined the faculty at Lowell Technological Institute—now the University of Massachusetts–Lowell—in 1973 and remained there for the rest of his career. He eventually became director of the UMass Lowell nuclear engineering program. After his retirement, he remained an emeritus professor at the university.
Sukesh Aghara, chair of the Nuclear Engineering Department Heads Organization, noted in an email to NEDHO members and others that “Gil was a relentless advocate for nuclear energy and a deeply respected member of our professional community. He was also a kind and generous friend—and one of the reasons I ended up at UMass Lowell. He served the university with great dedication. . . . Within NEDHO, Gil was a steady presence and served for many years as our treasurer. His contributions to nuclear engineering education and to this community will be dearly missed.”
E. R. Sanford, H. J. Litre
Nuclear Science and Engineering | Volume 4 | Number 6 | December 1958 | Pages 713-726
doi.org/10.13182/NSE58-A15494
Articles are hosted by Taylor and Francis Online.
An experiment was conducted in a critical assembly to determine water channel power peaking in a heterogeneous, highly enriched, water-moderated reactor subassembly. In addition to horizontal profiles of power density in a plane below a bank of control rods, data were obtained on the interacting effects of the control rod channel and bottom reflector power peaks. Experimental techniques are discussed. A computation for a comparable multiregion cell was made using a few-group diffusion theory digital computer code. Comparison of the results showed that variations in fast neutron spectrum and in manner of homogenization of materials within cell regions had no appreciable effects upon the power density peak. The choice of thermal neutron spectrum is important. Agreement between all experimental values and calculations with a Maxwellian spectrum was excellent. The comparison between experiment and calculations with a hardened thermal neutron spectrum was relatively poor. The results of this investigation indicate that great care must be exercised in interpreting experimental data on power distribution, and that two-dimensional diffusion theory calculations of power density are substantially verified. The use of U235 monitor foils is recommended in order to obtain a true fission power distribution. It was found that variations in the water gap width of the order of 10% had negligible effect upon the horizontal peak-to-average power ratio in the fuel. The use of metallic control rod extensions was found to decrease the horizontal peak-to-average ratio substantially, the magnitude of the decrease verifying analytical predictions.