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The spark of the Super: Teller–Ulam and the birth of the H-bomb—rivalry, credit, and legacy at 75 years
In early 1951, Los Alamos scientists Edward Teller and Stanislaw Ulam devised a breakthrough that would lead to the hydrogen bomb [1]. Their design gave the United States an initial advantage in the Cold War, though comparable progress was soon achieved independently in the Soviet Union and the United Kingdom.
Kristel Ghoos, Tucker McClanahan, Lukas Zavorka, Igor Remec
Nuclear Science and Engineering | Volume 198 | Number 2 | February 2024 | Pages 370-380
Research Article | doi.org/10.1080/00295639.2023.2233858
Articles are hosted by Taylor and Francis Online.
To organize the safe handling of activated material, knowing the residual dose rates is crucial. In this work, we present the pre-experiment activation analysis for an experiment in which tungsten blocks are irradiated by 800-MeV protons. In this analysis, we use the Monte Carlo N-Particle (MCNP) code for radiation transport, Attila4MC for unstructured mesh generation, and Activation in Accelerator Radiation Environments (AARE), including CINDER2008, for activation analysis. If the tungsten blocks must be removed within a day after the experiment, then exposure to personnel entering the room must be reduced. One exposure-reduction strategy is to add carbon steel shielding around the tungsten blocks, efficiently reducing the dose from the activated tungsten. However, the shielding becomes activated itself during irradiation: 56Mn is the dominant contributor for short decay times. The actual schedule at the time of the experiment allowed sufficient cool-off time for the tungsten in the room so that additional shielding was not necessary. A less rigorous comparison of the calculated values with the post-experiment measurements showed reasonable agreement.