Multishock Compression Properties of Warm Dense Argon

Abstract

Warm dense argon was generated by a shock reverberation technique. The diagnostics of warm dense argon were performed by a multichannel optical pyrometer and a velocity interferometer system. The equations of state in the pressure-density range of 20–150 GPa and 1.9–5.3 g/cm3 from the first- to fourth-shock compression were presented. The single-shock temperatures in the range of 17.2–23.4 kK were obtained from the spectral radiance. Experimental results indicates that multiple shock-compression ratio (ηi = ρi/ρ0) is greatly enhanced from 3.3 to 8.8, where ρ0 is the initial density of argon and ρi (i = 1, 2, 3, 4) is the compressed density from first to fourth shock, respectively. For the relative compression ratio (ηi’ = ρi/ρi-1), an interesting finding is that a turning point occurs at the second shocked states under the conditions of different experiments, and ηi’ increases with pressure in lower density regime and reversely decreases with pressure in higher density regime. The evolution of the compression ratio is controlled by the excitation of internal degrees of freedom, which increase the compression, and by the interaction effects between particles that reduce it. A temperature-density plot shows that current multishock compression states of argon have distributed into warm dense regime.

Electronic and optical properties of warm dense lithium: strong coupling effects

“…With the development of large facilities such as the National Ignition Facility [1], x-ray free electron laser [2,3], z-pinch [4,5] and multi-shock wave techniques [6], we can achieve more and more extreme conditions at high densities and temperatures. Most importantly, under these conditions, the systems, which are named warm or hot dense matter, cannot be considered as ideal gases.…”

Diagnostics and Production of Warm Dense Matter with Multishock Reverberation Compression Technique

“…We applied the above mention diagnostic technique and method to perform the experiments on warm dense H 2 , D 2 , He [33], H 2 +He [26], D 2 +He [32], Ne, Ar [34,35], and Xe [36,37] over several MPa to Mbar pressure region. The two-, four-, six-, and ten-shock in Xe, Ar, Ne, and low-Z gas (H 2 , D 2 , He, H 2 +He, D 2 +He) reverberate back and forth between the two high shock impedance of base-plate and window was directly observed in our experiments.…”

Thermodynamic and Kinetic Properties of Shocks in Two-Dimensional Yukawa Systems

“…Many limitations of hydrodynamic models of shock waves have been discovered using molecular dynamics (MD) simulations of hard-sphere gases [1,2] and softpotential molecular liquids [3][4][5][6][7][8][9][10]. Such a detailed understanding of shock waves is critical for a wide range of applications, including measurements of equations of state (EOS) [11,12], medical therapies [13][14][15], traffic flows [16], high explosives [17], granular flows [18], particle acceleration [19][20][21], and astrophysical phenomena (supernovae [22], cosmic rays [23,24], and solar wind [25]). In some fusion-energy devices [26][27][28][29], shock waves are used to compress a fuel to thermonuclear-burn conditions but are subject to detrimental hydrodynamic and kinetic instabilities.…”