[1] Synchrotron SOLEIL, F-91192 Gif Sur Yvette, France
[2] Univ P & M Curie Paris 6, CNRS, IMPMC, Phys Milieux Denses, F-75015 Paris, France
[3] Univ Witwatersrand, Sch Phys, Johannesburg, South Africa
[4] Univ Witwatersrand, DST NRF CoE Strong Mat, Johannesburg, South Africa