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Castle Bravo was the first in a series of high-yield thermonuclear weapon design tests conducted by the United States at Bikini Atoll, Marshall Islands, as part of Operation Castle. Detonated on 1 March 1954, the device remains the most powerful nuclear device ever detonated by the United States and the first lithium deuteride -fueled ...
But as was discovered in the first test of this type of device, Castle Bravo, when lithium-7 is present, one also has some amounts of the following two net reactions: 7 Li + 1 n → 3 T + 4 He + 1 n 7 Li + 2 H → 2 4 He + 1 n + 15.123 MeV. Most lithium is 7 Li, and this gave Castle Bravo a yield 2.5 times larger than expected. [16]
Operation Castle was an unqualified success for the implementation of dry fuel devices. The Bravo design was quickly weaponized and is suspected to be the progenitor of the Mk-21 gravity bomb. The Mk-21 design project began on 26 March 1954 (just three weeks after Bravo), with production of 275 weapons beginning in late 1955.
The atomic radius of a chemical element is a measure of the size of its atom, usually the mean or typical distance from the center of the nucleus to the outermost isolated electron. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius.
Comparative fireball radii for a selection of nuclear weapons. [citation needed] Contrary to the image, which may depict the initial fireball radius, the maximum average fireball radius of Castle Bravo, a 15-megatonne yield surface burst, is 3.3 to 3.7 km (2.1 to 2.3 mi), [6] [7] and not the 1.42 km displayed in the image.
The Bohr radius is consequently known as the "atomic unit of length". It is often denoted by a 0 and is approximately 53 pm. Hence, the values of atomic radii given here in picometers can be converted to atomic units by dividing by 53, to the level of accuracy of the data given in this table. Atomic radii up to zinc (30)
If the nucleus is assumed to be spherically symmetric, an approximate relationship between nuclear radius and mass number arises above A=40 from the formula R=R o A 1/3 with R o = 1.2 ± 0.2 fm. [6] R is the predicted spherical nuclear radius, A is the mass number, and R o is a constant determined by experimental
In a fission nuclear reactor, uranium-238 can be used to generate plutonium-239, which itself can be used in a nuclear weapon or as a nuclear-reactor fuel supply. In a typical nuclear reactor, up to one-third of the generated power comes from the fission of 239 Pu, which is not supplied as a fuel to the reactor, but rather, produced from 238 U. [5] A certain amount of production of 239