"SILEX": Iran's Undetectable Nuclear Enrichment Technology?

David P. Goldman  

"Laser uranium enrichment is so attractive that that it will be implemented --- and Iran will become the test case. What must be demanded is the complete opening of the country to appropriate inspection. Anything else would be too little – much too little." Hans Ruhle

German nuclear weapons expert Hans Rühle warned in the daily Die Welt May 21 that Iran can enrich uranium using laser technology that is much harder to detect than centrifuges. Rühle headed the German Defense Ministry's policy planning staff during the 1980s. In a widely-discussed commentary last February 17, he argued that Israel has the capacity to cripple Iran's nuclear weapons program. He also presented evidence in Die Welt that Iran may have tested a nuclear weapon in North Korea.

"Iranian President Mahmoud Ahmadihejad announced in 2010 the 'good nuclear news' that Iran then possessed laser technology for uranium enrichment. Iran would not use this technology immediately, Ahmadinejad insisted, but his extremely positive characterization of the new technological option casts strong doubt on Iran's intentions and suggests that Iran's voluntary restraint on enrichment is an attempt at diversion," Rühle wrote in his May 21 analysis.


"Laser enrichment is the silver bullet in this field," Rühle continues. "By the estimate of Australia's leading expert, laser enrichment is sixteen times more efficient than earlier enrichment technologies. This begs the question of why this sensational enrichment procedure was not put into effect earlier. The answer is that laser enrichment was long considered to be the technology of the future, too expensive and complicated for practical application."

As an alternative to mechanical separation of fissile uranium-235 through centrifuges, laser separation has been used experimentally since the 1960s, without bringing the new technique into industrial application. But the major nuclear powers had little incentive to invest in a new technology, Rühle argues, because their centrifuge installations could enrich uranium at comparatively low cost.
All that changed in 2006, Rühle adds, when an Australian laser enrichment technology, the "SILEX" method, began official tests. A billion-dollar laser enrichment facility is planned in the United States, large enough to provide enough fuel for 60 large reactors filling the energy needs of 60 million households. The facility could also produce enough highly-enriched uranium for 1,000 warheads per year.

Iran may have acquired laser enrichment technology from Russia, Rühle argues, starting with support for Iran's nuclear weapons program under agreements dating back to the Yeltsin administration. "It was no great surprise," Rühle argues, "that in the spring of 2000, America's spy services discovered a pilot program for laser enrichment between Iran and the D.V.-Efremov Institute in St. Petersburg. American diplomats at the time demanded that Russia cease this activity, on the stated grounds that "there can be no doubt that this installation can and will be turned to military nuclear applications in no time at all."

The project came up in talks between Presidents Clinton and Putin in September 2000, Rühle reports, and the Russians assured the American side that the project would be suspended pending an investigation: "That was a favorite Russian formula to remove controversial issues from current discussions and avoid potentially disadvantageous decisions, while shifting the project quietly to industrial and scientific institutes."

Ahmadinejad's boast that Iran possesses laser enrichment technology has a factual background, Rühle concludes. During the past year, the Vienna-based International Atomic Energy Agency has demanded on several occasions that Iran explain its laser enrichment program, with no response from the Iranian side.

If Iran has acquired this technology, it can enrich uranium far more cheaply and quickly, in inconspicuous facilities that are far harder to detect than centrifuge installations, Rühle warns. Laser enrichment requires a quarter of the physical space and much less energy than centrifuges. "For the international community's negotiations with Iran, this implies that what must be demanded is the complete opening of the country to appropriate inspection. Anything else would be too little—much too little."

Both in Germany and the United States, Rühle adds, the professional associations of nuclear physicists have warned about the consequences of uncontrolled dissemination of "SILEX" laser enrichment technology. "Despite all the experience of the preceding decades, this warning went heard," Rühle concludes. "Laser uranium enrichment is so attractive that it will be implemented—and Iran could become the test case."