55 research outputs found
PROBLEMS OF MEASUREMENT OF DENSE PLASMA HEATING IN LASER SHOCK-WAVE COMPRESSION
Experimental results of heating measurements of
matter carried out in a study of laser-driven shock waves
in aluminum (Batani et al. 1997) are discussed.
The measured temporal evolution of the "color"
temperature of the rear surface of the target is compared
with that computed by a numerical code. It has been established
that the target preheating can substantially affect optical
signal features recorded from the rear side of the target,
and consequently influence upon the accuracy of temperature
and pressure measurements of the material behind the shock
wave front
Dissipative solitary wave at the interface of a binary complex plasma
The propagation of a dissipative solitary wave across an interface is studied
in a binary complex plasma. The experiments were performed under microgravity
conditions in the PK-3 Plus Laboratory on board the International Space Station
using microparticles with diameters of 1.55 micrometre and 2.55 micrometre
immersed in a low-temperature plasma. The solitary wave was excited at the edge
of a particle-free region and propagated from the sub-cloud of small particles
into that of big particles. The interfacial effect was observed by measuring
the deceleration of particles in the wave crest. The results are compared with
a Langevin dynamics simulation, where the waves were excited by a gentle push
on the edge of the sub-cloud of small particles. Reflection of the wave at the
interface is induced by increasing the strength of the push. By tuning the ion
drag force exerted on big particles in the simulation, the effective width of
the interface is adjusted. We show that the strength of reflection increases
with narrower interfaces
The spall strength limit of matter at ultrahigh strain rates induced by laser shock waves
New results concerning the process of dynamic fracture of
materials (spallation) by laser-induced shock waves are presented.
The Nd-glass laser installations SIRIUS and KAMERTON were used
for generation of shock waves with pressure up to 1 Mbar in
plane Al alloy targets. The wavelengths of laser radiation were
1.06 and 0.53 μm, the target thickness was changed from
180 to 460 μm, and the laser radiation was focused in a
spot with a 1-mm diameter on the surface of AMg6M aluminum alloy
targets. Experimental results were compared to predictions of
a numerical code which employed a real semiempirical wide-range
equation of state. Strain rates in experiments were changed
from 106 to 5 × 107 s−1.
Two regimes of spallation were evidenced: the already known
dynamic regime and a new quasi-stationary regime. An ultimate
dynamic strength of 80 kbar was measured. Finally, experiments
on targets with artificial spall layers were performed showing
material hardening due to shock-wave compression
Ion stopping in dense plasma target for high energy density physics
The basic physics of nonrelativistic and electromagnetic ion stopping in hot and ionized plasma targets is thoroughly updated. Corresponding projectile-target interactions involve enhanced projectile ionization and coupling with target free electrons leading to significantly larger energy losses in hot targets when contrasted to their cold homologues. Standard stoppping formalism is framed around the most economical extrapolation of high velocity stopping in cold matter. Further elaborations pay attention to target electron coupling and nonlinearities due to enhanced projectile charge state, as well. Scaling rules are then used to optimize the enhanced stopping of MeV/amu ions in plasmas with electron linear densities nel ~ 10 18 -10 20 cm -2 . The synchronous firing of dense and strongly ionized plasmas with the time structure of bunched and energetic multicharged ion beam then allow to probe, for the first time, the long searched enhanced plasma stopping and projectile charge at target exit. Laser ablated plasmas (SPQR1) and dense linear plasma columns (SPQR2) show up as targets of choice in providing accurate and on line measurements of plasma parameters. Corresponding stopping results are of a central significance in asserting the validity of intense ion beam scenarios for driving thermonuclear pellets. Other applications of note feature thorium induced fission, novel ion sources and specific material processing through low energy ion beams. Last but not least, the given ion beam-plasma target interaction physics is likely to pave a way to the production and diagnostics of warm dense matter (WDM)
Thermodynamics and equations of state of matter: from ideal gas to quark-gluon plasma
The monograph presents a comparative analysis of different thermodynamic models of the equations of state. The basic ideological premises of the theoretical methods and the experiment are considered. The principal attention is on the description of states that are of greatest interest for the physics of high energy concentrations which are either already attained or can be reached in the near future in controlled terrestrial conditions, or are realized in astrophysical objects at different stages of their evolution. Ultra-extreme astrophysical and nuclear-physical applications are also analyzed where the thermodynamics of matter is affected substantially by relativism, high-power gravitational and magnetic fields, thermal radiation, transformation of nuclear particles, nucleon neutronization, and quark deconfinement. The book is intended for a wide range of specialists engaged in the study of the equations of state of matter and high energy density physics, as well as for senior students and postgraduates
Extreme states of matter: on earth and in the cosmos
With its many beautiful colour pictures, this book gives fascinating insights into the unusual forms and behaviour of matter under extremely high pressures and temperatures. These extreme states are generated, among other things, by strong shock, detonation and electric explosion waves, dense laser beams,electron and ion beams, hypersonic entry of spacecraft into dense atmospheres of planets, and in many other situations characterized by extremely high pressures and temperatures. Written by one of the world's foremost experts on the topic, this book will inform and fascinate all scientists dealing with materials properties and physics, and also serve as an excellent introduction to plasma-, shock-wave and high-energy-density physics for students and newcomers seeking an overview.
Extreme states of matter: high energy density physics
With its many beautiful colour pictures, this book gives fascinating insights into the unusual forms and behaviour of matter under extremely high pressures and temperatures. These extreme states are generated, among other things, by strong shock, detonation and electric explosion waves, dense laser beams,electron and ion beams, hypersonic entry of spacecraft into dense atmospheres of planets, and in many other situations characterized by extremely high pressures and temperatures.Written by one of the world's foremost experts on the topic, this book will inform and fascinate all scientists dealing with materials properties and physics, and also serve as an excellent introduction to plasma-, shock-wave and high-energy-density physics for students and newcomers seeking an overview. This second edition is thoroughly revised and expanded, in particular with new material on high energy-density physics, nuclear explosions and other nuclear transformation processes
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