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Iran and the Nuclear Weapons Triggers
The topic of countless bad science fiction movies, rogue nations getting and using nuclear weapons, moves from an ongoing nightmare of US and allied national security advisers, and closer to reality. Two nations are now under increased scrutiny for their alleged attempts to get atomic bombs. Recently, in Paris, an Iranian exile group -- the National Council of Resistance of Iran -- accused Tehran of using smuggled materials to conduct a secret program to develop a neutron initiator "nuclear trigger" using smuggled materials. Such a trigger would be used to detonate a fission bomb.
Most modern nuclear weapons use a neutron pulse tube, which accelerates tiny amounts of Tritium or Deuterium into each other, producing a reaction which then yields neutrons. The electronic pulse can be exactly controlled to nansecond or smaller accuracy to initiate the chain reaction. Polonium-Beryllium initiators were used in early weapons, and a third world bomb built from scratch is likely to use the same technology if such a country can manufacture it. In such a bomb, the limiting factor is the half-life of Polonium-210, which is about 140 days, meaning that the shelf life of such a bomb is about two years. A fission bomb can be detonated without such a trigger if enough of the nuclear material is quickly put close enough together. However, for such a bomb to work without a nuclear trigger, extremely precise manufacturing and precise control of the high explosive used to compress the radioactive material together is required. Such manufacturing finesse is said to be beyond the capability of most third world countries. Thus, countries with less sophisticated capabilities who want nuclear weapons must obtain suitable triggers.
The Iranian allegations made by the National Council of Resistance of Iran were met with some doubt since the group has a checkered record of reporting accurately some of the goings-on within Iran. However, Iran's repeated refusal to seriously negotiate with the West regarding abandoning a nuclear weapons program gives added credence to the group's claims and the International Atomic Energy Agency responded cautiously, noting that the Tehran Research Reactor may be in use through a dummy company to combine polonium-210 and beryllium to create a nuclear trigger.
This news comes upon the heels of word that North Korea has announced that it is again cutting food rations, refused to deny that it has purchased at least one nuclear weapon from abroad, and said it is rejoining multilateral talks aimed at preventing itself from acquiring nuclear weapons.
Posted by: Steve 2005-02-18
http://www.rantburg.com/poparticle.php?ID=56779