Phase transitions in shock compressed bismuth identified using single photon energy dispersive X-ray diffraction (SPEDX)

We present evidence for phase transitions in shock-compressed bismuth using the SPEDX x-ray diffraction technique. Experiments were performed on the Vulcan laser at the Central Laser Facility, RAL, Didcot, UK. We observed diffraction from the (110) bcc peak of Bi-V, and from its calculated lattice parameter the pressure was determined to be approximately 17 GPa. Upon further compression (higher laser intensities), no further diffraction from solid phases was observed. Shock melting of bismuth is thought to occur between 18 and 27 GPa. Diffraction results at lower pressures as a function of delay time are also presented. (paper)