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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.”
Jeremy Lloyd Conlin, James Paul Holloway
Nuclear Science and Engineering | Volume 169 | Number 2 | October 2011 | Pages 168-177
Technical Paper | doi.org/10.13182/NSE10-72
Articles are hosted by Taylor and Francis Online.
This paper introduces the explicitly restarted Arnoldi's method for calculating eigenvalues and eigenvectors in a Monte Carlo criticality calculation. Arnoldi's method is described along with the power method. The power method has been used for decades for Monte Carlo criticality calculations despite the availability of other algorithms with better convergence properties. The Monte Carlo application of the transport-fission operator of the Boltzmann transport equation is defined, and the Monte Carlo implementation of both Arnoldi's method and the power method are described. A brief discussion of eigenvalue and fission source convergence is given. Numerical simulations of one-demensional slab geometries are presented, demonstrating the convergence of both the eigenvalue and fission source (as measured by the Shannon entropy) for both Arnoldi's method and the power method. The results show that Arnoldi's method does not need to discard iterations like the power method because both the eigenvalue and fission source appear to converge immediately, even for problems with high dominance ratios.
