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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.”
M. T. Andrews, J. T. Goorley, E. C. Corcoran, D. G. Kelly
Nuclear Technology | Volume 187 | Number 3 | September 2014 | Pages 235-242
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-72
Articles are hosted by Taylor and Francis Online.
Study of the magnitude and temporal behavior of delayed neutrons (DNs) enables the identification of fissile isotopes and a determination of their relative quantities. Thus, the ability to model accurately these neutrons and the methods of their detection is of relevance to nuclear forensics and counterterrorism. The capability of MCNP6 to model these emissions was examined and compared to measurements of the DNs produced by 233U, 235U, and 239Pu after neutron-induced fission. Fissile samples were irradiated in a SLOWPOKE-2 research reactor for 60 s and were then conveyed via pneumatic tubing to an array of six 3He detectors embedded in a paraffin moderator. Several MCNP6 input files were created to reproduce irradiation conditions, temporal DN emission, and the detection arrangement. Nuclear reactions and other effects within the 3He detectors were reproduced by MCNP6, and detection efficiencies of this modeled arrangement determined by MCNP6 were in agreement with experimental measurements. Finally, the library and model DN emission options in the MCNP6v1 release were evaluated and compared to the measured magnitudes and temporal behavior of 233U, 235U, and 239Pu. Significant discrepancies observed between the DN model option and measurements for count times >100 s are discussed.
