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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.
Seiki Ohnishi, Fumiyoshi Nobuhara, Yoshihiro Hirao
Nuclear Science and Engineering | Volume 198 | Number 2 | February 2024 | Pages 517-526
Note | doi.org/10.1080/00295639.2023.2172309
Articles are hosted by Taylor and Francis Online.
Photon deep penetration calculations were conducted to create a buildup factor database for a new point kernel code. The calculations included the effects of photonuclear reactions, which were not considered in previous buildup factor calculations, and the target energy was extended up to 30 MeV. For media with large photonuclear cross sections, the contribution of the neutron dose becomes significant. For example, in iron at 80 mean free paths, the total dose is 1024 times larger than when the photonuclear reactions are not considered. On the other hand, it was found that if photonuclear reactions are ignored, the calculation results are not necessarily conservative in media with a significant neutron shielding capacity, such as water.