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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.”
Gabriel Ghita, Glenn Sjoden, James Baciak
Nuclear Technology | Volume 159 | Number 3 | September 2007 | Pages 319-331
Technical Paper | Radiation Protection | doi.org/10.13182/NT07-A3879
Articles are hosted by Taylor and Francis Online.
Plutonium-beryllium (Pu-Be) sources can be used as didactic source materials for special nuclear materials (SNM) detection evaluation protocols. Since limited specific information exists for many of the Pu-Be sources currently in service, before using a Pu-Be source for field studies, the leakage radiation of neutrons and gamma rays from the source must be fully assessed. Most Pu-Be sources have an outer stainless steel jacket and an inner tantalum jacket, with the Pu-Be homogeneously distributed throughout the inner jacket. To fully characterize the net leakage terms from our Pu-Be source, we applied three-dimensional radiation transport computations, including Monte Carlo (MCNP5) and deterministic (PENTRAN) methodologies. The transport model for our Pu-Be capsule is based on limited schematic and technical data. To define the decay history and resulting source spectrum, exothermic [alpha-neutron (,n)] reactions are modeled using OrigenArp in the SCALE5 package. For transport modeling purposes, the intermetallic Pu-Be compound was treated as an intimate mixture of plutonium and beryllium, based on the manufacturer's mass specifications. The net capsule leakage was derived using transport computations, and an iterative estimation of plutonium age was performed. Computational results for net leakage are in agreement with the manufacturer's specification of neutron yield and dose rate. We also combined computational results with experimental measurement data to fully validate our computational methods. We have successfully achieved agreement between computational and experimental data for our Pu-Be source leakage, and we are using the results at the Florida Institute of Nuclear Detection and Security to evaluate a prototype SNM neutron detector array for parcel screening and national security applications.