title: X-ray scattering measurements of strong ion-ion correlations in shock-compressed aluminum.
abstract: The strong ion-ion correlation peak characteristic of warm dense matter (WDM) is observed for the first time using simultaneous angularly, temporally, and spectrally resolved x-ray scattering measurements in laser-driven shock-compressed aluminum. Laser-produced molybdenum x-ray line emission at an energy of 17.9 keV is employed to probe aluminum compressed to a density of ρ>8 g/cm(3). We observe a well pronounced peak in the static structure factor at a wave number of k=4.0 Å(-1). The measurements of the magnitude and position of this correlation peak are precise enough to test different theoretical models for the ion structure and show that only models taking the complex interaction in WDM into account agree with the data. This also demonstrates a new highly accurate diagnostic to directly measure the state of compression of warm dense matter.
authors: Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors: T
authors: T
authors: Ma
authors: T
authors: T
authors: Döppner
authors: R W
authors: RW
authors: Falcone
authors: L
authors: L
authors: Fletcher
authors: C
authors: C
authors: Fortmann
authors: D O
authors: DO
authors: Gericke
authors: O L
authors: OL
authors: Landen
authors: H J
authors: HJ
authors: Lee
authors: A
authors: A
authors: Pak
authors: J
authors: J
authors: Vorberger
authors: K
authors: K
authors: Wünsch
authors: S H
authors: SH
authors: Glenzer