This image provided by the Department of Energy shows a screen shot of the National Institute of Standards and Technology's Mass Spectral Search Program, which depicts the chemical spectral ... more 
This image provided by the Department of Energy shows a screen shot of the National Institute of Standards and Technology's Mass Spectral Search Program, which depicts the chemical spectral fingerprint of sarin at the Pacific Northwest National Labratory in Richland, Wash. Three simple numbers will prove if sarin was used to gas Syrians last month: 99-125-81. Carlos Fraga , a chemist at the lab who specializes in nerve agent forensics calls those numbers sarin’s fingerprint. Fraga says once chemists see those digits, they know they’ve got sarin.(AP Photo/Department of Energy, Carlos Fraga) less 
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Associated Press | Photo By Department of Energy, Carlos Fraga
Fri, Sep 6, 2013 4:08 AM EDT