The hydrodynamic response of metal targets to volume heating by energy deposition of intense heavy-ion beams was investigated experimentally. Recent improvements in beam parameters led to a marked increase in specific deposition power: 2·101040Ar18+ ions of 300 MeV/u focused to a spot size of 300 μm (σ) × 540 μm (σ) yield a specific deposition energy in solid lead of approximately 1 kJ/g in the Bragg peak, delivered within 250 ns [full width at half maximum (FWHM)]. This value allowed us for the first time to observe heavy-ion-beam-induced hydrodynamic expansion of metal volume targets. Measurements comprise expansion velocities of free surfaces of up to 290 ± 20 m/s, surface temperatures of ejected target matter of 1600–1750 K, and pressure waves in solid metal bulk targets of 0.16 GPa maximum absolute value and 0.8 μs FWHM. The experimental results agree well with the results of a 2D hydrodynamic code. Inside the interaction zone, which can only be accessed by simulation, maximum temperatures are 2800 K and maximum pressures are 3.8 GPa.

Modeling plus simulations using the one-dimensional Lagrangian radiation-hydrodynamics code HYADES are compared with data from classical and ablative Rayleigh–Taylor experiments conducted on the Nova laser. Comparisons between the experiments and modeling for both the gross hydrodynamic motion and the perturbation evolution are made and show good agreement. A third order perturbation analysis is applied to demonstrate the onset of nonlinearity. A simple, physically intuitive saturation model is used to describe the growth further into the nonlinear regime. Finally, we present the first comparison of the Betti ablation front theory with indirect-drive RT data and obtain good agreement.

Experiments were performed using high-power laser pulses (greater than 50 TW) focused into underdense helium, neon, or deuterium plasmas (ne ≤ 5 × 1019 cm−3). Ions having energies greater than 300 keV were measured to be produced primarily at 90° to the axis of laser propagation. Ion energies greater than 6 MeV were recorded from interactions with neon. Spatially resolved pinhole images of the ion emission were also obtained and were used to estimate the intensity of the focused radiation in the interaction region.

Beam-generated magnetic fields strongly influence the behavior of relativistic electron guns. Existing methods used in ray-tracing codes have limited accuracy and may not correctly represent nonlaminar beams. We describe a technique for the magnetic field calculation in a two-dimensional code based on the assignment of particle currents to the faces of elements in the mesh used for the electrostatic calculation. The balanced calculation of electric and magnetic forces in the same iteration cycle reduces the possibility of numerical filamentation instabilities. With simple rules of assignment on boundary faces, the method also handles field contributions of electrode currents. Several benchmark calculations performed on conformal meshes illustrate the versatility of the technique.

Significant interest has recently focused on the use of liquid-metal targets flowing with high velocities for various high-power nuclear and high-energy physics applications such as fusion reactor first-walls, the Spallation Neutron Source, Isotope Separation On Line, and Muon Collider projects. This is because the heat generated in solid targets due to beam or plasma bombardment cannot be removed easily and the resulting thermal shock damage could be a serious lifetime problem for long-term operation. More recently, the use of free or open flying-liquid jets has been proposed for higher-power-density applications. The behavior of a free-moving liquid mercury or gallium jet subjected to proton beam deposition in a strong magnetic field has been modeled and analyzed for the Muon Collider project. Free-liquid-metal jets can offer significant advantages over conventional solid targets, particularly for the more demanding and challenging high-power applications. However, the use of free-moving liquid-metal targets raises a number of new and challenging problems such as instabilities of the jet in a strong magnetic field, induced eddy-current effects on jet shape, thermal-shock formation, and possible jet fragmentation. Problems associated with shock heating of liquid jets in a strong magnetic field are analyzed in this study.

Magnetohydrodynamic simulation results related to the capillary discharge dynamics are presented. The main physical process that should be taken into account is the ablation of the capillary wall material evaporated by the heat flux from the capillary plasma. The possible applications of the capillary discharges related to the physics of the X-ray lasers and the use of the capillary plasma to provide a guiding for ultrashort high-intensity laser pulses over a distance greater than the defocusing length are discussed.

This article reports on the interaction between slow ions and a partially ionized plasma. Temporal evolutions of energy loss and charge distribution of 2.4 MeV oxygen beams in the laser-induced polyethylene plasma were measured. The charge distribution showed strong stripping ability in the early phase of the plasma. Stopping power deduced from the experimental energy loss was 1.9 times larger than that for the solid. The effective charge of the projectile ion was estimated from the yields of 4+ and 6+ states. The peak value of the effective charge was 1.4 times larger than that of the solid. The stopping power equation given by Sigmund was extended for the partially ionized plasma and it could reproduce the measured energy loss.

An energy loss of 240 MeV argon ions in a Z-pinch helium plasma has been for the first time observed throughout the entire pinching process. Standard Stark broadening analysis gives an electron density ranging from 4 to 6 × 1017 cm−3 during the pinch. To deduce stopping power from the energy loss, the target thickness of the helium plasma has been evaluated assuming the mean charge of helium based on thermal equilibrium. The observed electron density and the mean charge of helium give a target thickness of 30 ± 3 μg cm−2 from 1 μs to 1.8 μs after the discharge ignition. The measured stopping power exceeds a tabulated value for cold helium gas by a factor of 2 to 3 around the time of the first pinch. The experimental stopping power is compared with theoretical values calculated using an equation of stopping power for a partially ionized plasma.

Calculations of optimal parameters for the e-beam excited Xe spontaneous radiation source (excilamp) at λ ∼ 172 nm have been done. There have been defined optimal values of gas density and specific excitation power. Gas temperature dependence of radiation conversion efficiency related to the injected media energy have been also computed. It has been shown that there is an optimum in excitation pulse duration at frequency operation mode.

We derive optimum values of parameters for laser-driven flights into low Earth orbit (LEO) using an Earth-based laser, as well as sensitivity to variations from the optima. These parameters are the ablation plasma exhaust velocity vE and specific ablation energy Q*, plus related quantities such as momentum coupling coefficient Cm and the pulsed or continuous laser intensity that must be delivered to the ablator to produce these values. Different optima are found depending upon whether it is desired to maximize mass m delivered to LEO, maximize the ratio m/M of orbit to ground mass, or minimize cost in energy per gram delivered. Although it is not within the scope of this report to provide an engineered flyer design, a notional, cone-shaped flyer is described to provide a substrate for the discussion and flight simulations. The flyer design emphasizes conceptually and physically separate functions of light collection at a distance from the laser source, light concentration on the ablator, and autonomous steering. Approximately ideal flight paths to LEO are illustrated beginning from an elevated platform. We believe LEO launch costs can be reduced 100-fold in this way. Sounding rocket cases, where the only goal is to momentarily reach a certain altitude starting from near sea level, are also discussed. Nonlinear optical constraints on laser propagation through the atmosphere to the flyer are briefly considered.

Resonant absorption of first-overtone (FO) CO laser radiation by atmospheric water vapor and various organic and nonorganic pollutants is discussed. Suitable ro-vibrational lines are selected for their potential use in traditional spectroscopic schemes of atmospheric pollution diagnostics. Nonlinear atmospheric absorption of intense multiline FO CO laser radiation is simulated and laser-induced changes in absorption spectra are demonstrated. Absorption coefficients of a few substances on several FO CO ro-vibrational lines are experimentally measured. A comparative analysis of spectral characteristics of an FO CO laser and an HF (DF) laser demonstrates that the potential of FO CO laser applications for spectroscopic detection of various molecular trace gases is greater than that of HF and DF lasers.

This book treats the most widespread application of high-power laser materials processing, that is, CO2 laser cutting. Although called CO2 laser cutting, most of the content of the book is also valid for cutting with other lasers such as Nd:YAG or Cu Vapor lasers. The technology is described in a very useful style by emphasizing practical aspects and by replacing highly scientific phrases by clear, illustrative explanations. Nevertheless, this guide through the complex field of laser cutting is accompanied by critical physical explanations throughout the whole book. It should be emphasized that Dr. Powell is the technical director of two job shops on laser cutting, but has also been highly active in science for many years. This ideal combination of practical experience with scientific know-how is reflected throughout the whole book by highlighting the practical aspects of laser cutting, often accompanied by very critical scientific explanations. It should be noted that the present second edition of the book differs from the first edition, printed in 1993, only by several pages that had to be updated according to the state of the art.

When this remarkable book appeared in 1992, it became an instant classic. Combined with its precursor volume by the same authors, Photons and Atoms: An Introduction to Quantum Electrodynamics, these works deftly illuminate the central interactions between light and matter. I refer the reader to the excellent review of Atom–Photon Interactions: Basic Processes and Applications by T.A. Brian Kennedy (American Journal of Physics 61(6), 1993, p. 572).

This book succeeds in providing an experimentalist's view of quantum optics, complementing the many standard texts which take a theoretical point of view (see, e.g., M.O. Scully and M.S. Zubairy Quantum Optics, Cambridge University Press, 1997). As the title indicates, the book focuses mainly on experimental efforts and the realistic conditions of experimental tests. The choice of topics was clearly the result of the author's experience in the field of experimental quantum optics and a solid understanding of the pedagogical requirements of the material.

This monograph, updated from the first edition of 1994, is a thorough and timely addition to the increasing set of texts on microsystems technology (MST). It is valuable since it concentrates on a vital area of development—laser MST techniques—and presents a detailed overview of many of the applications areas in this rapidly expanding field.

The reviewed book deals with the scattering and absorption of light by small particles as well as with the radiative transfer process. These phenomena are fundamental to the study of disperse systems of various natures. That is why the results obtained are important in a very wide range of applications in optics of atmosphere and ocean, cell biology, colloidal chemistry, astrophysics, and astronomy. The well-thought-out structure of the text, happy choice of topics, precise definitions introduced preceding every consideration, and numerous useful tables make it possible to recommend the book for researchers in many fields.