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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.”
Pramila Mohan, Rajesh Mohan, Feroz Ahmed, L. S. Kothari, Hiroyuki Kadotani
Nuclear Science and Engineering | Volume 94 | Number 1 | September 1986 | Pages 87-93
Technical Note | doi.org/10.13182/NSE86-A17121
Articles are hosted by Taylor and Francis Online.
The multigroup space eigenvalues and eigenfunctions of a one-dimensional steady-state diffusion theory operator have been used to study the spatial behavior of a fast neutron field in certain thorium systems. The nuclear data used are from the 26-group ABBN data set. It has been shown that for a fast thorium system, unlike a fast uranium system, all the space eigenvalues lie in the continuum and no discrete space eigenvalue exists. A fast thorium system behaves more like a fast nonmultiplying system. The spectra shifts continuously to lower energies as one moves away from the source; however, pseudoasymptotic conditions are established in certain distance ranges. In order to test the validity of the diffusion theory and eigenfunction expansion method, results have also been obtained using transport theory. In all cases the two sets of results are in reasonably good agreement. To see the effect of geometry, the spectra at certain distances inside a 1-m-thick thorium slab are compared with the corresponding spectra inside a thorium sphere of 1-m radius. At all distances the normalized slab and sphere spectra are nearly the same.
