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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
R. Gwin, D. W. Magnuson
Nuclear Science and Engineering | Volume 12 | Number 3 | March 1962 | Pages 359-363
Technical Paper | doi.org/10.13182/NSE62-A28086
Articles are hosted by Taylor and Francis Online.
The values of eta for U233 and eta for Pu239 have been determined by a reactivity coefficient measurement. An aqueous solution of each isotope was introduced axially into a critical cylindrical annular flux trap reactor, and the resulting reactivity change was measured by period determinations. From these data the ratios and were obtained. Using recently measured values of eta for U235 and the absorption cross sections in this ratio, the thermal values of 2.317 ± 0.040 for eta of U233 and 2.032 ± 0.053 for eta of Pu239 are obtained. Correction to a neutron velocity of 2200 meters/sec by using the appropriate g-factor gives a value of 2.317 ± 0.040 for eta of U233 and 2.082 ± 0.054 for eta of Pu239.