[1] Chicago Ctr Cosmochem, Chicago, IL USA
[2] Univ Chicago, Dept Geophys Sci, 5734 S Ellis Ave, Chicago, IL 60637 USA
[3] Univ Chicago, Enrico Fermi Inst, 5640 S Ellis Ave, Chicago, IL 60637 USA
[4] Washington Univ, Space Sci Lab, St Louis, MO USA
[5] Washington Univ, Dept Phys, St Louis, MO 63130 USA
[6] Max Planck Inst Chem, Mainz, Germany
[7] Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA