We present results of studies of the behavior of a laser-produced plasma in a strong external transverse magnetic field of above 10 T in induction generated from a flat teflon target at the laser power densities of about 1014 W/cm2. In the measurements of plasma parameters, a two-channel automated interferometric system (Pisarczyk et al. 1994) was applied. The interferometric measurements have shown that the transverse magnetic field induces an asymmetry of the plasma distinctly apparent in the interferograms registered in two mutually perpendicular directions. Due to the lack of axial symmetry of the plasma, the Abel's transformation could not be applied in quantitative processing of the interferograms. To reconstruct a spatial distribution of electron density in a plasma stream of disturbed axial symmetry, a methodology prepared for this experiment was used. Analyzing the spatial and temporal distributions of electron concentration obtained in the transverse magnetic field, it has been proved that the factor responsible for the disturbance of the axial symmetry of the plasma is the Rayleigh–Taylor (R–T) instability corresponding to the ion unmagnetization state.

The role played by the angle of incidence of a short pulse laser in the generation of magnetic field via Weibel instability from overdense plasmas is investigated with the help of three-dimensional particle-in-cell simulations. The simulations have been done for different cases by varying the angle of incidence. When the laser pulse is incident normally (θ = 0°), it gets self-focused at a very short distance and the axial intensity rises up to several times the fundamental laser intensity. Strong current filamentation is observed, which causes the generation of high magnetic fields across the current filament. When the laser is incident obliquely at θ = 30° and 60°, periodic density ripple-like structures are formed on the plasma surface which is due to emission of energetic electron jets caused by vacuum heating. The periodic structures carry forward and return currents, which results in the formation of periodic magnetic field structures having strong magnetic fields. At θ = 60°, the inter spacing distance coincides with the incident laser wavelength. The magnetic energy is found to be highest in case of normal incidence, which is due to strong current filamentation. The filamentation becomes weaker as the angle of incidence is increased.

Recent advances of the photon kinetic theory are illustrated here, with examples taken from plasma physics (forward Raman scattering), and from nonlinear optics (self-phase modulation). This theory can provide a unified view of nonlinear optical phenomena involving photon beams with an arbitrary spectrum.

The effect of arbitrary shapes of the two fluid interface on Richtmyer-Meshkov (RM) instability is investigated. It is seen that deviation from sinusoidality in the geometrical shapes has interesting influence on the overall growth rate. In the linear theoretic domain the RM instability may be actually reduced for suitable geometrical shape of the interface. The figures given demonstrate this aspect. This result is important in designing ICF target and also gives an idea to tailor laser pulse for optimum stability of RM modes.

This paper investigates the focal location effects on the penetration depth of molten region surrounding a paraboloid of revolution-shaped cavity (i.e. keyhole of this model) irradiated by a moving focused energy beam, which profile of intensity is assumed to be Gaussian distribution. Considering the momentum balance at the base of the keyhole, a quasi-steady-state thermal model relative to a constant-speed moving high-energy beam and paraboloid of revolution-shaped cavity is developed in a parabolic coordinate system. The analytical solution is obtained for this model with the adiabatic condition directly set on the workpiece surface for semi-infinite domain instead of the image method for infinite domain using the separation-of-variables method. The analytical solution of this model gives a reasonable prediction for the cavity temperatures. The predicted relation of the penetration depth to the focal location agrees with the available measured data. The effects of focal convergence angle and spot size on the penetration depth are also discussed.

The behavior of the stimulated Raman scattering is investigated in a laser-irradiated plasma with an inhomogeneous density profile, by means of wave-coupling simulations. In the case of a regular hydrodynamic-like profile, a spectral broadening is observed when the laser irradiance is increased and is found to result from a coupling between the convective and the absolute Raman scattering, via pump depletion. In the case where a short-scale modulation of the density is superimposed on the profile, the spectrum is strongly influenced by the propagation velocity of the modulation and by the sinusoidal/chaotic nature of the modulation.

In this work the construction characteristics and performances of a laser system operating with an e-beam sustained discharge are described. Operating with XeCl, the laser pulse energy is over 4 J. Details of the measurements on the system are also reported.

In this article we describe a new ray-trace code. This code is a three-dimensional description of the beam propagation, including the half cavity mirror. It is based on the integration of the ray equation and on the calculation of the intensity along the plasma. It works as a postprocessor of the hydrodynamic/atomic code “EHYBRID,” which calculates the time evolution of the gain, emissivity, electronic density, and the width of the plasma. We present results obtained on different schemes of X-ray laser generation.

We are working on the generation of the high-power UV pulse by backward Raman pulse amplification. This report deals with the generation of the high-power backward first Stokes light using a simple focusing geometry. The high-power Stokes light, which grows from spontaneous scattered light in the focal region, can be obtained by focusing the high-energy KrF pump pulse into a Raman cell filled with methane gas. The intensity of the pump pulse increases significantly near the focus. This pulse produces a serious effect of the nonlinear refractive index. We mixed xenon gas into the Raman medium to compensate for this effect. As a result, a stable generation of the high-power single backward first Stokes light can be obtained.

Experimental spectra of hot dense plasmas of aluminium produced by the interaction of a subpicosecond laser with solid targets at 1016 and 5 × 1017 W/cm2 are analyzed and discussed. A detailed analysis of the K-shell spectra is given through time-dependent calculations of atomic physics postprocessed to Fokker-Planck calculations of the laser-matter interaction. The non-Maxwellian character of the electron distribution function is shown. An evaluation of the electronic density and of the ion temperature 7i will be presented through Stark line broadening calculations. An X-ray spectrum from a Tantalum target also will be presented along with a preliminary interpretation.

The first International Conference on the Frontiers of Plasma Physics and Technology was organized in Bangalore, India during December 9–14, 2002. More than 100 delegates from all the continents participated in the conference and about half the delegates were from overseas. This Forum specially encouraged the young researchers to present their work and exchange ideas with experts. This conference which was inter-disciplinary in nature, brought several plasma physicists and technologists to a common platform to discuss the research and applications useful for the advancement of the present society.

An experiment has been performed with the LULI Multi-TeraWatt Laser. The acceleration of electrons injected in a plasma wave generated by the laser wakefield mechanism has been observed with a maximum energy gain of 1.5 MeV. It has been shown that the electrons deflected during the interaction, could scatter on the walls of the experimental chamber, and fake a high-energy signal. A special effort has been given in the electron detection to separate the accelerated electrons signal from the background noise.The experimental results agree with theoretical predictions and numerical simulations when 3D effects on the electron beam are taken into account.

The colliding shock lens is described briefly. Possible applications, industrial drilling and cutting, laser Q-switching and spatial filtering, ultrahigh-power applications, and “all gas lasers” are proposed. The time evolution, scaleability, and repetition rate operation are investigated.

As an important part of my duty and as a first step as incoming editor to this journal it is a great pleasure for me to thank Professor George H. Miley for his work that he did for over a decade as the editor-in-chief of Laser and Particle Beams. During a period of over 20 years, the field, which this journal has set out to address, has experienced enormous progress. George H. Miley steered the journal safely through uncharted waters and always found a way to keep the delicate balance between the needs of readers, authors, and the publisher as well. The journal is now regarded to be highly prestigious and it is listed among the top ranking scientific journals with peer review systems. When we compare this journal to others, we have to keep in mind that it is not made by professional journalists but rather by fellow scientists for scientists. During all these years George Miley managed to have this journal serve the needs of the scientific community and he was very successful in this difficult enterprise. Thank you George!

The process of induced bremsstrahlung is studied and it is found that anisotropy in the electron distribution can lead to the amplification of radiation. The gain rate is ,Λ where ν is the electron-ion collision frequency, ωp and ω the plasma and radiation frequency, and Λ a numerical factor which is positive only for anisotropic distributions.

Intense ion beams can be used to generate ultrahigh pressures in condensed matter. Lightion beams generated at the Karlsruhe Light Ion Facility (KALIF) typically have a focus of less than 1-cm diameter. The maximum power density at KALIF achieved so far is of the order of 1 TW/cm2. In the energy deposition zone of the targets, the 1.5-MeV protons of the KALIF beam deposit energy of the order of 100 TW/g or 5 MJ/g. A strongly coupled, hot, dense plasma is thus created by the action of a light ion beam on matter. The high pressure generated in this region has been used to accelerate thin foils to velocities up to 12.5 km/s. A successful interpretation of these experiments can serve as a check of theoretical models and of the equation of state (EOS) data. The present paper contains an investigation of the hydrodynamics of thin aluminum foil accelerated by light ion beams at KALIF using Bθ0-diode. The peak power density in these experiments was 0.15 ± 0.05 TW/cm2. The results of simulations depend mainly on two factors: power density evolution at the target and the EOS for the strongly coupled dense and hot plasma. The beam power density evolution has been carefully remeasured recently. It turned out that the available EOS data do not reproduce experimental results satisfactorily. We have formulated a simple EOS formula in a modified Mie-Grüneisen form. We assume the Grüneisen parameter to be a function of temperature and density. The parameters of this EOS have been adjusted to reproduce experiments at KALIF. In the present paper analysis of beam-target interaction experiments at KALIF is presented using our analytic EOS. We show that such experiments can give information on EOS data in the region of strongly coupled plasma.

The interaction of light with the intergalactic plasma produces the Hubble red shift versus distance relationship. This interaction also produces an isotopic long wavelength background radiation from the plasma. Intrinsic red shifts in quasars and other objects are similarly explained, showing why they are exceptions to Hubble's law. Because the red shift is not doppler-shifted, big bang cosmological models should be replaced with static models.

Ignition with the help of a shock wave is performed by the interaction of accelerated plasma block by a petawatt-picosecond (PW-ps) laser, with a solid-state density fuel that it is a new possibility for achieving controlled fusion by inertial confinement. The unexpected production of plasma blocks provides new access to the ignition of solid-state density fuel according to the Chu hydrodynamic model. When the produced plasma block by the PW-ps laser hits the main fuel due to the density differences between the plasma block and the main fuel of the shock wave, this progressive wave increases the density of solidified fuels and reduces the energy of the ignition threshold and increases the flammability. In this study, a new discovery of shock waves has been observed leading to the resonance phenomenon. Nuclear heat shock waves resonance in the side-on ignition of fuel in the internal layer of fuel at x ≠ 0 appears from the exact solution of the hydrodynamic equations with respect to the density profile. This important finding achieves the required ignition temperature for solid-state fuel deuterium–tritium (D–T) in certain energies, with a significant increase due to the resonance of thermonuclear waves. This discovery will facilitate practical experiments on the ignition of advanced solid-state fuels with the accelerated plasma blocks by a PW-ps laser at certain energies.