We have focused our attention on the stopping mechanisms involved in the recently proposed ion beam-target US program. This mechanism emphasizes out production of warm dense matter through pulsed ion beams, linearly accelerated, and interacting with thin foils in Bragg peak conditions. We reviewed the relevant energy loss mechanisms involved at moderate and low velocity ion projectile. Small velocities close to zero are given some attention.

Starting from the Riemann-Silberstein formulation of classical electrodynamics the Schrödinger equation for the photon energy wave function is discussed. Hereafter, a propagator description of the space-time emission of a polychromatic photon from an atom is presented, paying particular attention to the near-field electrodynamics. When the atom is embedded in a solid-state plasma the photon emission process can be dramatically modified. Limiting the analyses to solid-state plasmas exhibiting translational and rotational symmetry, the near-field atom-photon-plasma interaction is studied paying particular attention to the plasmariton and plasmon excitation processes. It is shown that the transverse and longitudinal parts of the plasma-screened field propagator link in a direct manner to the free-photon propagator and the longitudinal near-field photon propagator. The necessity of keeping both the transverse and longitudinal parts of the plasma screening in a rigorous description of near-field electrodynamics is demonstrated.

In this paper, potential of diagnostics with the use of Kα radiation for an energy deposition process from an intense ion-beam to background plasma is considered quantitatively. Kα radiation is a good candidate for the purpose. The wavelength of Kα radiation is varied according to the charge state of an emitter atom, and the diagnostics spatially resolved with radiations from various kinds of charge states can give us a profile of plasma temperature in a target material. For the calculation of Kα yield, an atomic population kinetics code is developed, and the result shows that Kα radiation has potential to get information of a plasma profile heated by an intense ion-beam.

The purpose of the present paper is to describe the effects of electron-electron collisions on proton electronic stopping in plasmas of any degeneracy. Plasma targets are considered fully ionized so electronic stopping is only due to the free electrons. The stopping due to free electrons is obtained from an exact quantum mechanical evaluation in the random phase approximation, which takes into account the degeneracy of the target plasma. The result is compared with common classical and degenerate approximations. Differences are around 30% in some cases which can produce bigger mistakes in further energy deposition and projectile range studies. We focus our analysis on plasmas in the limit of weakly coupled plasmas then electron-electron collisions have to be considered. Differences with the same results without taking into account collisions are more than 50%.

Numerical simulations of the Rayleigh-Taylor instability in the interface of two semi-infinite media have been performed based on the finite element method. Two different interfaces have been considered: elastic solid/elastic solid and elastic solid/viscous fluid. The results have been compared with previously published analytical models. In particular, the asymptotic growth rate has been compared with the model by Terrones (2005) while the initial transient phase is compared with the model by Piriz et al. (2005). Finally, some examples show the importance of such an initial transient phase if more realistic material laws (for example, elastoplastic behavior) are taken into account.

We study the motion of a classical relativistic charged particle in the electromagnetic field of a Bessel beam exhibiting vector optical vortices, and show how its dynamical properties, such as linear and angular momentum, are transmitted to the particle. The effects of different polarizations are taken into account using transverse electric and magnetic modes, and their superpositions. The constants of motion are identified for the most general case. We report typical numerical results for axial and radial motion for various configurations, with an estimate of expected axial accelerations when transverse magnetic Bessel modes are used. The Lorentz transformation properties of the field are used throughout in order to simplify the calculations.

The transport of high-current heavy-ion beams in plasma channels is a promising option for the final transport in a heavy-ion fusion reactor, since it simplifies the construction of the reactor chamber significantly. Our experiments at the Gesellschaft für Schwerionenforschung demonstrate the creation of 1 m long stable plasma channels and the transport of heavy-ion beams. The article outlines the experimental setup used at GSI and reports the results of beam transport measurements using these long channels. The experiments demonstrate good beam transport properties of the channel, indicating that channel transport is a viable alternative to neutralized-ballistic transport.

In the fast ignition scenario for inertial fusion, a relativistic electron beam is supposed to travel from the side of the fusion pellet to its core. One one hand, a relativistic electron beam passing through a plasma is a highly unstable system. On the other hand, the pellet core is denser than its side by four orders of magnitude so that the beam makes its way through a important density gradient. We here investigate the effect of this gradient on the instabilities. It is found that they should develop so early that gradient effects are negligible in the linear phase.

An important component of the U.S. effort to achieve thermonuclear ignition in 2010 on the National Ignition Facility is the development of high quality 2 mm diameter spherical capsules to function as the ablator and contain the cryogenic DT fuel. Three ignition capsule designs have been developed, and detailed fabrication specifications for each design have been established and placed under change control. A research program with activities coordinated mainly between Lawrence Livermore, General Atomics and Los Alamos is underway to demonstrate fabrication of capsules meeting specifications. The point design for ignition campaigns beginning in 2010 is a Cu-doped Be capsule that has a radial gradient in Cu dopant level in the capsule wall. This capsule is being produced by sputter deposition of Be and Cu onto either a hollow glow discharge polymer (GDP) spherical mandrel or a solid spherical mandrel, followed by removal of the mandrel and polishing of the capsule. A key goal in the U.S. is to demonstrate fabrication of this capsule by the end of 2006. Two other ignition capsule designs are also being developed as contingencies to the point design. One contingency design is a GDP capsule that has a radial Ge dopant level in its wall. This capsule is produced by co-deposition of Ge and GDP onto a PAMS mandrel followed by thermal removal of the mandrel. The second contingency design is a uniform Cu-doped Be capsule that is fabricated from high purity fine grain Be0.3at.%Cu alloy using a precision machining route followed by polishing. Ignition targets to be fielded in 2010 will be filled with DT fuel through a small fill hole. Laser drilling capability has been developed and used to drill approximately 5 μm diameter holes through capsule walls for DT filling. Characterization methods necessary for characterizing capsules are being developed.

We perform the analysis of the Rayleigh–Taylor instability of thin perfectly elastic solid plates using the analytical approach recently developed by Piriz and coworkers. The model describes the evolution of the perturbation amplitude from the initial conditions and at relatively long times it yields the asymptotic growth rate. It applies to solid/inviscid fluid interfaces. For the particular case of solid/vacuum interface, the model has been compared with the exact results by Plohr and Sharp and an excellent agreement has been found. In general, thinner plates are found to be more unstable and, in the presence of a fluid below the elastic plate, the growth rate is reduced.

The existing “quotidian equation state” model, based on Thomas-Fermi theory, is modified so as to improve the low density region of phase diagram of metals. A scheme for estimating the critical parameters of liquid-vapor phase transition is proposed. The new model reproduces experimental critical isotherms to a good degree of accuracy. Furthermore, the proposed model is validated with thermodynamic data in the liquid-vapor co-existence region, including results on isobaric expansion as well as released isentropes.

We study the details of a gradual change in electron properties from those of a nearly-free-electron (NFE) metal to those of a strongly-coupled plasma, in ultrashort pulse energy deposition in solid metal targets. Time scales shorter than those of a target surface layer expansion are considered. Both the case of an optical laser (visible or near infrared wavelengths range) and of a free electron laser (vacuum ultraviolet or X-ray) are treated. The mechanisms responsible for the change in electron behavior are isochoric melting, lattice charge disordering, and electron mean free path reduction. We find that the transition from metal to plasma usually occurs via an intermediate stage of a charge-disordered solid (solid plasma), in which ions are at their lattice sites but the ionization stages of individual ions differ due to ionization from localized bound states. Charge disordered state formation is very rapid (typically, few femtoseconds or few tens of femtoseconds). Pathway to charge-disordered state differs in simple metals and in noble metals. Probabilities are derived for electron impact ionization and 3-body recombination of a bound ionic state in solid-density medium, applicable both in metal and in plasma regime. An evolution of energy coupling between electron and ion subsystems, from metallic electron-phonon (e-ph) to plasma electron-ion (e-i) coupling, is considered. Substantial increase in coupling parameter is expected as a result of charge disorder.

Laser acceleration of electrons in laser fields of intensities above 1028 W/cm2 were found to be in the same range as acceleration at the surface of black holes, where the laser intensities are in the range of pair production in vacuum due to vacuum polarization. The results in connection with the black holes arrived at similarities to the Hawking and Unruh radiation. We present here results based on the thermodynamics of the vacuum fluctuations that there is a difference between Hawking and Unruh effects in connection with the Casimir effect in view of the vacuum properties for laser produced pairs in a vacuum.

The experience of target fabrication with low-density and cluster heterogeneity is presented. Cluster plasma research is strongly dependent on target fabrication development and target structure characterization. Ten more target parameters should be measured for experiment interpreting in case of micro-heterogeneous plasma. Foam and foil targets, high-Z doped also, are produced and irradiated on the existing laser facilities. The density of 4.5 mg/cc cellulose triacetate in the form of regular three-dimensional polymer networks are achieved which is as low as plasma critical density for the third harmonic of iodine laser light. The possibilities of varying important target parameters, methods of their monitoring are discussed. Experiments with underdense foam targets with or without clusters irradiated on Prague Asterix Laser System (PALS) laser facility are analyzed preliminary for target optimization. Under-critical foams of varying structure (closed-cell foam or three-dimensional networks) and densities are reported for plasma experiments. Thermal and radiation transport in such targets are considered.

The problem of nonlinear self-focusing of elliptic Gaussian laser beam in collisionless magnetized plasma is studied using variation approach. The dynamics of the combined effects of nonlinearity and spatial diffraction is presented. With a and b as the beam width parameters of the beam along x and y directions, respectively, the phenomenon of cross-focusing is observed where focusing of a results in defocusing of b and vice versa. Although no stationary self-trapping is observed, oscillatory self-trapping occurs far below the threshold. The regularized phase is always negative.

We have demonstrated the acceleration of a monoenergetic electron beam by a laser-produced wakefield. Experiments were performed by focusing 2-TW laser pulses of 50 fs on supersonic gas-jet targets. The focused intensity was 5 × 1018 W/cm2 (a0 = 1.5). At an electron density of 1.5 × 1020 cm−3, the clear monoenergetic electron beam from the plasma was obtained at 7 to 15 MeV. The Stokes satellite peak in the forward scattering explained the energy spectra of electrons at various plasma densities well. Although the wakefield propagated 500 microns, which was far beyond the dephasing length, monoenergetic electron beams were obtained.

Stochastic pulsation of laser-plasma interaction in the range of a few to dozens of picoseconds, due to standing wave produced density ripples, needs more attention than in the past, in view of the recent developments. This is important if nanosecond laser pulses produce a pre-compression that is a thousand times the solid state density of DT for fast ignition as well as for treatment of ps laser interaction. The following is an updated summary of these properties where the laser beam smoothing is essential. The use of smoothing is not only an empirical game with experiments for improving the interaction, but it is necessary to be aware of the mechanisms involved for understanding how the pulsation is overcome, and conclusions can be derived systematically for further improvements and control of the phenomena.

Magnetic confinement fusion (MCF) and inertial confinement fusion (ICF) are critically contrasted in the context of far-distant travels throughout solar system. Both are shown to potentially display superior capabilities for vessel maneuvering at high speed, which are unmatched by standard cryogenic propulsion (SCP). Costs constraints seem less demanding than for ground-based power plants. Main issue is the highly problematic takeoff from earth, in view of safety hazards concomitant to radioactive spills in case of emergency. So, it is recommended to assemble the given powered vessel at high earth altitude ∼ 700 km, above upper atmosphere. Fusion propulsion is also compared to fission powered one, which secures a factor of two improvement over SCP. As far a specific impulse (s) is considered, one expects 500–3000 from fission and as much as 104–105 from fusion through deuterium–tritium (D-T). Next, we turn attention to the most performing fusion reaction, i.e., proton–antiproton annihilation with specific impulse ∼ 103–106 and thrust–to–weight ratio ∼ 10−3–1. Production and costs are timely reviewed. The latter could drop by four orders of magnitude, which is possible with successful MCF or ICF. Appropriate vessel designs will be presented for fusion as well as for antimatter propulsion. In particular, ion compressed antimatter nuclear II (ICAN-II) project to Mars in 30 days with fusion catalyzed by 140 ng of antiprotons will be detailed (specific impulse ∼ 13500 s).

We describe here the present status of the Advanced Laser Light Source (ALLS) facility, a state-of-the-art multi-beam Ti:sapphire laser system presently under construction in Canada. ALLS is a national user facility to be commissioned in 2005 at the INRS campus near Montreal. The 25 fs ALLS multi-beam laser system has three components, each with different repetition rate and output energy. These multiple laser beams will be used to generate a “rainbow” of femtosecond pulses from the far infrared to hard X-rays, which can be combined to perform unique experiments, such as dynamic molecular imaging. In this paper, we describe two examples of experiments that are planned by our group with the ALLS facility. The first is the highly efficient generation of high-order harmonics using ablation medium. We demonstrate the generation of up to the 53rd harmonics (λ = 15 nm) of a Ti:sapphire laser pulse (150 fs, 10 mJ), using pre-pulse (210 ps, 24 mJ) produced boron ablation as the nonlinear medium. The second example is the demonstration of in-line phase-contrast imaging with an ultrafast (300 fs) laser-based hard X-ray source (Mo K-α line). Images of biological samples have shown great enhancement of contrast due to this technique, distinguishing details that are barely observable or even undetectable in absorption images.

A new laser-driven ion acceleration mechanism has been identified using particle-in-cell (PIC) simulations. This mechanism allows ion acceleration to GeV energies at vastly reduced laser intensities compared with earlier acceleration schemes. The new mechanism, dubbed “Laser Break-out Afterburner” (BOA), enables the acceleration of carbon ions to greater than 2 GeV energy at a laser intensity of only 1021 W/cm2, an intensity that has been realized in existing laser systems. Other techniques for achieving these energies in the literature rely upon intensities of 1024 W/cm2 or above, i.e., 2–3 orders of magnitude higher than any laser intensity that has been demonstrated to date. Also, the BOA mechanism attains higher energy and efficiency than target normal sheath acceleration (TNSA), where the scaling laws predict carbon energies of 50 MeV/u for identical laser conditions. In the early stages of the BOA, the carbon ions accelerate as a quasi-monoenergetic bunch with median energy higher than that realized recently experimentally.