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Going Nuclear: Notes from the officially unofficial book tour
I work in the analytical labs at one of Europe’s oldest and largest nuclear sites: Sellafield, in northwestern England. I spend my days at the fume hood front, pipette in one hand and radiation probe in the other (and dosimeter pinned to my chest, of course). Outside the lab, I have a second job: I moonlight as a writer and public speaker. My new popular science book—Going Nuclear: How the Atom Will Save the World—came out last summer, and it feels like my life has been running at full power ever since.
G. Kistner and J. T. Mihalczo
Nuclear Science and Engineering | Volume 35 | Number 1 | January 1969 | Pages 27-44
Technical Paper | doi.org/10.13182/NSE69-A21112
Articles are hosted by Taylor and Francis Online.
A series of static critical experiments has been performed on an accurate mockup of the SORA Reactor. SORA is a proposed NaK cooled, repetitively pulsed fast reactor which would be used as a high-intensity neutron source for time-of-flight experiments. The reactivity of this reactor is varied by a movable reflector. Those parameters which are related to the kinetics of the reactor have been investigated thoroughly in the critical experiments. They have been measured for both beryllium and iron reflectors of several sizes and for various core and fixed reflector configurations. The total reactivity of the movable reflectors varied from $3.7 for a 11.0-cm-wide iron reflector to $12 for a 26.2-cm-wide beryllium reflector. The reactivity of the movable reflector as a function of its position has been shown to have a parabolic dependence on position characterized by the parameter αx, which varied from 4 to 9.9¢/cm2. The prompt-neutron time decay is described by a fast decay constant which varied between 0.30 and 0.55/µ sec and a slow decay constant which varied between 0.05 and 0.10/µ sec. The critical mass for the various experiments was between 50.3 and 57.3 kg of uranium enriched to 93.2 wt% 235U. Using space-independent neutron kinetics with one delayed-neutron group, it has been shown that with a 24-cm-high × 7-cm-thick × 21-cm-wide beryllium reflector the assembly will produce 100 pulses/sec ∼50-µsec wide at half-maximum power with a peak-to-average power ratio of ∼180.