> On Sun, 24 Nov 2002, Ulhas Joglekar wrote:
>
> > I have read about nuclear bombs weighing 5 kilograms.
>
> But those were plutonium bombs, right? For those, the lower limit seems
> to be 3 kg (with very sophisticated techniques). But for enriched
> uranium, I believe the lower limit is 25 kg.
I quoted from memory from an article in the Bulletin of Atomic Scientists, "India's silent bomb" by David Albright and Mark Hibbs:
"In the absence of information about the amount of plutonium needed for an Indian bomb, we assume about 6 kilograms of plutonium for each weapon, a higher than normal value. If India uses Cirus plutonium, then it probably has enough for about 50 weapons.
By the end of 1995, India could have a stockpile of about 400 kilograms, with the bulk of the additional 100 kilograms produced in the Dhruva reactor. In all, this would give India enough plutonium for 65 weapons.
India is also moving toward realization of large-scale use of uranium 233 as fuel for its power reactors. Uranium 233 is a fissile isotope of uranium that requires about as much material per bomb as plutonium. Uranium 233 is made by irradiating natural, non-radioactive thorium in a reactor, and India attaches a high priority to the development of thorium/uranium 233 fuel for its power reactors. Irradiation of thorium in the Cirus, Dhruva, and the MAPS reactors has resulted in the production of kilogram quantities of uranium 233."
Ulhas