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Breaking ground on a new approach to construction
The drive to Kairos Power’s reactor demonstration site in Oak Ridge, Tenn., is not only scenic—it’s historic. Nearly 85 years ago, roughly 30,000 construction workers transformed orchards and farmland into a key Manhattan Project site. Depending on your route, you may pass by one of the three gatehouses that were once military checkpoints controlling access to Atomic Energy Commission production facilities.
Andrew J. Hummel, Todd S. Palmer
Nuclear Science and Engineering | Volume 183 | Number 1 | May 2016 | Pages 149-159
Technical Note | doi.org/10.13182/NSE15-37
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The most widely used and versatile medical radioisotope today is 99mTc. Roughly 30 million people depend on this radioisotope for diagnostic imaging procedures each year, and this demand is expected to grow. Although there are numerous ways of producing this isotope, the most common is from fission product 99Mo, which is produced in all nuclear reactors fueled with 235U as a fission fragment with a yield of around 6.1%. Molybdenum-99 has a half-life of just over 2.5 days, and it will decay to 99mTc 87% of the time. The Reduced Enrichment for Research Test Reactors program was established at Argonne National Laboratory in 1978 to investigate technology that would aid in converting highly enriched uranium (HEU) facilities to low-enriched uranium (LEU) fuel. Since the majority of all 99Mo produced currently comes from the irradiation of HEU fuel targets, there has been a growing effort to design LEU targets that can yield comparable quantities of high specific activity 99Mo. Recently, a novel LEU target design has been developed for use in TRIGA reactors for the production of 99Mo. The simulation tool MCNP5 was used to examine the neutronic behavior of multiple core configurations fueled solely with this new target.