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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.”
B. S. Sandhu
Nuclear Technology | Volume 175 | Number 1 | July 2011 | Pages 118-123
Technical Paper | Special Issue on the 16th Biennial Topical Meeting of the Radiation Protection and Shielding Division / Radiation Measurements and General Instrumentation | doi.org/10.13182/NT11-A12279
Articles are hosted by Taylor and Francis Online.
The objective of this work is to present a method/technique for the determination of the effective atomic number (Zeff) of composite materials [mixed materials of many atomic numbers (Z's)]. In the present measurements, an intense beam of gamma-ray photons irradiates targets of different elements and composite materials and of varying thicknesses. The scattered radiations are detected by a properly shielded NaI(Tl) scintillation detector whose response unfolding, converting the observed pulse-height distribution to a true photon spectrum, is obtained with the help of an inverse matrix approach. This also results in the extraction of the numbers of multiple-scattered events from the thick targets. We observe that the numbers of multiple-scattered events, having the same energy as in single-scattered distribution, increase with an increase in target thickness and then saturate for a particular target thickness known as saturation thickness (depth). The saturation thickness is found to decrease when the Z of pure elements increases. A calibration curve (saturation depth versus Z of pure elements) and the measured saturation thickness values for composite materials are used to assign the respective Zeff values of these composite materials. Monte Carlo calculations also support the present experimental results.
