Inferring the electron temperature and density of shocked liquid deuterium using inelastic X-ray scattering

Journal article

An experiment designed to launch laser-ablation-driven shock waves (10 to 70 Mbar) in a planar liquid-deuterium target on the OMEGA Laser System and to diagnose the shocked conditions using inelastic x-ray scattering is described. The electron temperature (T e) is inferred from the Doppler-broadened Compton-downshifted peak of the noncollective (α s = 1kλ D > 1) x-ray scattering for T e > T Fermi. The electron density (n e) is inferred from the downshifted plasmon peak of the collective (α scatter > 1) x-ray scattering. A cylindrical layer of liquid deuterium is formed in a cryogenic cell with 8-μm-thick polyimide windows. The polyimide ablator is irradiated with peak intensities in the range of 10 13 to 10 15 W/cm 2 and shock waves are launched. Predictions from a 1-D hydrodynamics code show the shocked deuterium has a thickness of ∼0.1 mm with spatially uniform conditions. For the drive intensities under consideration, electron density up to ∼5 × 10 23 cm -3 and electron temperature in the range of 10 to 25 eV are predicted. A laser-irradiated saran foil produces Cl Ly αemission. The spectrally resolved x-ray scattering is recorded at 90° for the noncollective scattering and at 40° for the collective scattering with a highly oriented pyrolytic graphite (HOPG) crystal spectrometer and an x-ray framing camera. © 2010 IOP Publishing Ltd.

Authors: Regan, S; Radha, P; Boehly, T; Doeppner, T; Falk, K

• Journal: Journal of Physics: Conference Series
• Volume: 244
• Issue: PART 4
• Pages: 042017-042017
• Publication date: 2010-01-01
• DOI: 10.1088/1742-6596/244/4/042017
• EISSN: 1742-6596
• ISSN: 1742-6588
• Language: English