Talk:Fat Man

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This article was the subject of a Wiki Education Foundation-supported course assignment, between 7 January 2019 and 23 April 2019. Further details are available on the course page. Student editor(s): Jroshco.

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The article may or may not correctly describe the core as a "sphere". It's certainly possible that the Pu was formed into a solid sphere, and only reached "critical mass" (density) with the shaped charges. In fact the article discusses that a bit. However, a lot of (sloppy) discussion about spherical shells describe them as "spheres". (Of course, a beach ball is (approximately) a sphere of plastic and air. But it's not a plastic sphere!) What I'd like to see here is that if the editor means solid sphere s/he say that, and if the meaning is spherical shell, then it should be pretty clear that that term needs to be used. I'm now not certain that my understanding of the Fat Boy core (a spherical shell compressed by the detonation of many shape charges) is correct. In other words, this article leaves me more confused that before I read it. That's not good.174.130.71.156 (talk) 07:42, 5 January 2023 (UTC)[reply]

You'll get quite a bit of detail from this description of the core, written by data engineer (non-physicist) Carey Sublette. Scroll down to 8.1.1.1 The Pit Assembly. Sublette describes a plutonium-gallium alloy formed into a mostly solid sphere but with a small cavity at the center, holding a two-piece neutron initiator. The word "hollow" doesn't work here because it gives a sense of having a relatively thin shell, but the core was thick. Binksternet (talk) 09:48, 5 January 2023 (UTC)[reply]

At the bottom of the color key in the Assembly section is a note that indicates the uranium tamper contributed up to 20 percent of the weapon's final yield. A paragraph following then seems to contradict this saying the uranium tamper contributed 30 percent. Is this a misread on my part, a broad approximation, or something else? Each seems to cite a difference source. Even if I misread it still seems confusing. Maybe this could be generalized into "20-30%" kind of compromise? StrontiumDogs (talk) 22:28, 10 July 2023 (UTC)[reply]

Checked both sources in case it was a typo. Both are correctly cited. But Wellerstein cites a more recent and comprehensive source, so used the 30% figure. Hawkeye7 (discuss) 23:54, 10 July 2023 (UTC)[reply]