Prof David Clark

MoSE 3201A
Wednesday, October 16, 2019 - 3:00pm to 4:00pm
Synchrotron Studies for Nuclear Security


For over 25 years, Los Alamos National Laboratory has been using synchrotron-produced x- rays at
Stanford Synchrotron Radiation Lightsource (SSRL) in support of nuclear security research.    
Currently,  electronic  structure  studies  in  the  Tender  X-ray  region  are  giving insights  
on  closing  the  nuclear  fuel  cycle,  and  hard  x-ray  micro-spectroscopy  on  single particles
is of growing interest for nuclear forensics and environmental science applications. Over the last
decade, x-ray absorption spectroscopy studies helped guide cleanup decisions of  contaminated  
Superfund  Sites;  and  helped  table  plans  for  a  new  US  nuclear  weapon’s production
facility.  I will give highlights of these studies and offer my perspective on future opportunities
for synchrotron x-ray spectroscopy to contribute new science in support of nuclear security.

  Actinide Covalency                     Chernobyl Particles                 Superfund Cleanup

Figure. (Left), Chlorine K-edge x-ray absorption spectroscopy has been used to probe covalent
mixing in the metal-ligand bond of octahedral MCl62- complexes, providing spectroscopic evidence
for involvement of both 5f and 6d orbitals in actinide metal-ligand bonds.   (Center), Microfocused
x-ray beams can image small particles through the use of element specific x-ray fluorescence,
giving rise to element maps that show the concentrations of contaminants, (Right) Aerial photos of
the Rocky Flats nuclear weapons production facility in 1995 and after remediation and cleanup,
guided by x-ray absorption studies of plutonium in soil, groundwater and concrete.


Contact Information: 
Host:  Prof Henry LaPierre
Map of Georgia Tech

School of Chemistry & Biochemistry

901 Atlantic Drive Atlanta, GA 30332-0400

(404) 894-4002 (phone) | (404) 894-7452 (fax)