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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.”
R. A. Karam, W. Y. Kato
Nuclear Science and Engineering | Volume 52 | Number 2 | October 1973 | Pages 201-208
Technical Paper | doi.org/10.13182/NSE73-A28189
Articles are hosted by Taylor and Francis Online.
Systematic errors responsible for the large discrepancy between the measured and calculated central reactivity coefficients were examined. These errors were narrowed to two sources: the normalization integral (or perturbation denominator) and the conversion factor of inhour, or dollars, to Δk/k units. The magnitude of both sources of error is uniquely determined by the ratio of the measured-to-calculated normalization integral when the measurement is carried out using the 252 Cf source-reactivity method. The measured-to-calculated normalization integral ratios for ZPR-6 Assemblies 6A and 7, two typical demo-plant-size Liquid Metal Fast Breeder Reactor criticals, were 1.19 and 1.21, respectively. The magnitude of this discrepancy is essentially the same as that found for the central reactivity coefficient. Analysis of the available fission rate distribution in both assemblies indicates that the calculated normalization integral may be underestimated by 6 to 8% and that the remainder of 10 to 14% must come from the conversion factor. The delayed-neutron data of Krick and Evans, when used with the appropriate average number of neutrons per fission in each assembly, yield conversion factors 9 to 13% higher than the delayed-neutron data of Keepin. This would provide the explanation of the central reactivity discrepancy. Unfortunately, the method of calculating βeff could also produce errors of this magnitude even if one has an absolutely correct set of delayed-neutron fractions. More definitive measurements of the delayed-neutron fractions of pertinent isotopes, as a function of the incident neutron energy, are needed. In addition, measurements of βeff in various assemblies by different methods are required.
