Watch out for the Big Bad Row
The IAEA submitted its latest report on Iran’s nuclear programme to its board of governors on 26th May. (via V Anantha Nageswaran). The report points out that Iran has been operating its assembly of 3000 IR-1 centrifuges at the Natanz Fuel Enrichment Plant with greater efficiency and is in the process of adding another similar assembly. It is experimenting with advanced centrifuge designs (modified Pakistani P2 designs, replacing maraging steel rotors with carbon fibre composite ones), although these remain employed in the pilot stage.
The IAEA report finds Iran guilty of both procedural violations (reporting installations post facto, rather than in advance) as well as for not providing satisfactory accounts of alleged weapons development activities (preparing an underground shafts for testing, testing detonators and warhead designs, and modifying the Shahab-3 ballistic missile to carry a nuclear warhead). [See Arms Control Wonk‘s post]
So what does this tell us about the all important question: when will Iran have a bomb ready?
Assuming that Iran does not have other secret nuclear plants well hidden from the public eye, the reasonable assumption is that Iran will use the Natanz facilities to produce highly enriched uranium (HEU) that will go into its bomb. According to Jeffrey Lewis’ handy calculator, Iran will need between 156 to 293 days to produce enough HEU for a bomb. If it gets the second assembly of 3000 centrifuges operating, that period will be halved, to about 78-147 days. As Dr Lewis’s calculations show, the time to produce sufficient HEU gets shorter if more centrifuges become operational, or their efficiency improves.
In addition to having sufficient quantities of HEU, Iran must also have a functioning weapons design—again thanks to Pakistan and A Q Khan, that should not be too difficult.
But Iran’s centrifuges are not yet producing HEU. The IAEA is keeping watch over the nuclear material and the centrifuge cascades in the Natanz facility. It is likely to know if and when the Iranian authorities decide to go into the bomb mode. A possible indicator of this happening is when Iran and the IAEA have the Big Bad Row. Depending on how many centrifuges Iran has working then, we can estimate the time it will take to produce and assemble a bomb. That could be anywhere between 78 days (if the second assembly is operational) to 293 days (if only the existing one is operational). If you are looking for a ready reckoner: you can assume that Iran has the bomb three months from the Big Bad Row.