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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Dragonfly, a Pu-fueled drone heading to Titan, gets key NASA approval
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
Michael Täschner, Claus Bunnenberg, Henry Camus, Yves Belot
Fusion Science and Technology | Volume 28 | Number 3 | October 1995 | Pages 976-981
Tritium Safety | Proceedings of the Fifth Topical Meeting on Tritium Technology in Fission, Fusion, and Isotopic Applications Belgirate, Italy May 28-June 3, 1995 | doi.org/10.13182/FST95-A30532
Articles are hosted by Taylor and Francis Online.
Although the process of tritium reemission from soils after HT or HTO deposition is principally understood, the prediction of initial values and time courses of reemission rates on the basis of readily available data is still insufficient, especially when high time resolutions are required. Theoretical and experimental investigations discussed here show that for a yet limited number of environmental conditions good model performance is reached. In the case of evaporation conditions the initial reemission rate after HT deposition can be coupled to the evaporation rate, when the tritium profile in soil is of exponential shape, characterized by a mean scaling length. After HTO deposition the ideal profile can be described by an error function with a scaling length about 1/3 of that of the HT case. Hence, the initial reemission rate is 3 times higher. Time courses can be modeled by a diffusion approach applying the same diffusion coefficient as for the deposition process.