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Nuclear Energy Conference & Expo (NECX)
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.”
J. A. Gomez, P. E. Koehler, T. E. Cutler, A. DeYoung, J. T. Goorley, J. D. Hutchinson, G. McKenzie, G. L. Morgan, S. M. Mosby, W. L. Myers, R. S. Rundberg, V. W. Yuan
Nuclear Science and Engineering | Volume 193 | Number 5 | May 2019 | Pages 537-548
Technical Paper | doi.org/10.1080/00295639.2018.1545956
Articles are hosted by Taylor and Francis Online.
Neutron diagnosed subcritical experiments (NDSEs) aim to measure the fission chain decay of subcritical test objects initiated by neutrons from an external source. The ultimate goal of future NDSEs is to make such measurements on dynamic subcritical objects as they are imploded. As a step toward that goal, we made measurements on three static subcritical assemblies containing highly enriched uranium. Specifically, we measured the die-off of both fission gamma rays and neutrons, with nanosecond resolution over several hundred microseconds, relative to the emission time of neutrons from a source in close proximity to the subcritical objects. As simulations are expected to play a key role in interpreting future NDSEs, we compared our data to detailed MCNP® calculations. There was good agreement between the data and MCNP over die-off times expected to be most important to future NDSEs, but there were significant differences at both earlier and later times. We attempted to reconcile these differences by several changes to the simulations. In particular, we found that reducing the 235U(n,n’) cross section to 80% of the current ENDF7.1 evaluation resulted in much better agreement.