Interesting article in the NY Times about how scientists in nuclear research labs in the US aided the negotiations with Iran

It was over one of those dinners in Vienna last summer that several of the experts began wondering how they might find a face-saving way for Iran to convert its deep-underground enrichment plant at Fordo, a covert site exposed by the United States five years ago, into a research center. That would enable Iran to say the site was still open, and the United States could declare it was no longer a threat.“The question was what kind of experiment you can do deep underground,” recalled a participant in the dinner.

Source: Atomic Labs Across the U.S. Race to Stop Iran – NYTimes.com