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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.”
Pietro Mosca, Claude Mounier, Pierre Bellier, Igor Zmijarevic
Nuclear Science and Engineering | Volume 175 | Number 3 | November 2013 | Pages 266-282
Technical Paper | doi.org/10.13182/NSE12-63
Articles are hosted by Taylor and Francis Online.
This paper shows two ways to improve the accuracy of the transport calculations. These improvements, implemented in the APOLLO2 code, concern the fission source calculation and the self-shielding models. The calculation of the fission source was generalized to fission spectra including an incident neutron energy dependence. The subgroup self-shielding model was updated for a mixture of resonant nuclides. Some tests on fast neutron systems like a critical sphere without reflector, a sodium-cooled cell, and a helium-cooled cell show that the use of four optimized incident macro groups for fission spectra guarantees a correct representation of the fission source.The tests on a critical sphere with a thick steel reflector and on a water-moderated mixed oxide cell prove that the subgroup self-shielding, accounting for the mutual shielding of several resonant nuclides, allows us to improve the accuracy of the neutron transport solution.