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Re: [Phys-l] dealing with the media +- evolution

At 22:39 -0500 4/5/08, cliff parker wrote:

There is only one
reason for Iran to produce enriched uranium and that is to eventually have
the capability to produce atomic bombs.

I suspect that is true, but it remains conjecture, since we don't have evidence yet that they are attempting to enrich uranium beyond about 10%. And although all reactors produce plutonium, not all plutonium is suitable for use in nuclear weapons. The longer the uranium fuel stays in the reactor, the more it becomes contaminated with Pu-240, and if the concentration of Pu-240 gets to be more than about 10%, then the Pu produced in the reactor won't make very good bombs, due to the high rate of spontaneous fission that Pu-240 undergoes, which speeds the explosive fission up to the point where it is too fast for the critical mass assembly to complete before the weapon blows itself apart.

It doesn't mean that the weapon won't work at all, just that it will be a lower yield than can be obtained with weapons grade plutonium (>90% Pu-239). It is the fact that non-weapons-grade Pu can still be used to build nuclear weapons, albeit of lower efficiency, that makes the reprocessing of spent fuel a serious weapons proliferation risk, and thus something that should be strongly discouraged, aside from the fact that reprocessed fuel is about 3 times as expensive as once-through fuel, as well as a major chemical pollution source due to the complex refining process required to separate the plutonium from the rest of the spent fuel.

A breeder reactor designed to produce weapons grade plutonium has to have its fuel rods changed on about a one-two month schedule. Pure power reactors leave the fuel rods in place for 3-4 years (changing 1/3-1/4 of the rods each year).

Now a reasonable argument may
perhaps be made concerning the right of a country such as Iran to possess
such a bomb but no reasonable argument exists as to why they are enriching

In fact, Iran put its right to obtain nuclear weapons on hold when it signed the NPT. Of course they can withdraw from the NPT, as North Korea did, but so far, they haven't seen fit to do so. Technically, therefore, they do not at present have the right to build nuclear weapons.

However, the NPT also says that the nuclear weapons nations are obligated to assist non-weapons nations to obtain peaceful nuclear power, and both Russia and the US have been very reluctant to abide by that article of the NPT, so Iran has essentially taken that as an excuse to build their own enrichment capability (the Russian-built plant at Bushehr, is almost complete, but Russia still hasn't delivered the fuel to run it), claiming that they have that right as part of the NPT. I think the NPT is a bit vague on that point, so they may be able to stretch it to cover their enrichment plant.

Unfortunately, the NPT is a deeply flawed document, creating a two-tier structure of nations--the weapons haves and have-nots. It forbids the have-nots from obtaining weapons, and enjoins the haves from taking steps to reduce their inventories, ultimately to get rid of them altogether. So far the haves have been quick to demand that the have-nots live up to their end of the bargain, but very reluctant to do anything toward living up to their end. And, at least in the case of Iran and Norht Korea, the haves have been reluctant to honor their obligation to assist the have-nots in obtaining peaceful nuclear power.

Furthermore, the US, in particular, has been instrumental in preventing the disarmament conference that is supposed to be working toward strengthening the NPT from achieving anything.

If Iran decides to leave the NPT, then it will no longer be bound by its restriction on obtaining nuclear weapons, but other nations are also no longer bound to offer them any further assistance on their nuclear power program. So are, Iran has seen greater advantage to them in staying inside the NPT structure. That may change.


Hugh Haskell

(919) 467-7610

Hard work often pays off after time. But Laziness always pays off now.

February tagline on 2007 Demotivator's Calendar