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Energy- and temperature relaxation processes after laser excitation of the electrons in solids and warm dense matter take place in virtually every high-energy density experiment and play an important role in a great number of industrial processes. In inertial fusion, they are essential for a successfull burn phase of the hydrogen pellet. Here, we report on new theoretical and experimental results concerning the energy transfer between electrons and phonons in solid aluminium on a femto to pico-second timescale. The results suggest that the two-temperature model is insufficient to describe the relaxation. We instead introduce a non-thermal lattice model. Within this model, electron-phonon couplings as derived from density functional theory and Bragg-peak decay rates as measured via electron diffraction are consistent with each other.

As computing power becomes more and more available, robotic systems are moving away from active sensors for environmental awareness and transitioning into passive vision sensors. With the advent of teleoperation and real-time video tracking of dynamic environments, the need to stabilize video onboard mobile robots has become more prevalent. This thesis presents a digital stabilization method that incorporates inertial fusion with a Kalman filter. The camera motion is derived visually by tracking SIFT features in the video feed and fitting them to an affine model. The digital motion is fused with a 3 axis rotational motion measured by an inertial measurement unit (IMU) rigidly attached to the camera. The video is stabilized by digitally manipulating the image plane opposite of the unwanted motion. The result is the foundation of a robust video stabilizer comprised of both visual and inertial measurements. The stabilizer is immune to dynamic scenes and requires less computation than current digital video stabilization methods.

Laser-plasma accelerated ion and electron beam sources are an emerging field with vast prospects, and promise many superior applications in a variety of fields such as hadron cancer therapy, compact radioisotope generation, table-top nuclear physics, laboratory astrophysics, nuclear forensics, waste transmutation, Special Nuclear Material (SNM) detection, and inertial fusion energy. LANL is engaged in several projects seeking to develop compact high-current and high-energy ion and electron sources. We are especially interested in two specific applications: ion fast ignition/capsule perturbation and radiation oncology. Laser-to-beam conversion efficiencies of over 10% are needed for practical applications, and we have already shown inherent efficiencies of >5% from flat foils, on Trident using only a 5th of the intensity [1] and energy of the Nova Petawatt laser [2]. With clever target designs, like structured curved cone targets, we have also been able to achieve major ion energy gains, leading to the highest energy laser-accelerated proton beams in the world [3]. These new target designs promise to help usher in the next generation of particle sources realizing the potential of laser-accelerated beams.

Laser-plasma accelerated ion and electron beam sources are an emerging field with vast prospects, and promise many superior applications in a variety of fields such as hadron cancer therapy, compact radioisotope generation, table-top nuclear physics, laboratory astrophysics, nuclear forensics, waste transmutation, Special Nuclear Material (SNM) detection, and inertial fusion energy. LANL is engaged in several projects seeking to develop compact high-current and high-energy ion and electron sources. We are especially interested in two specific applications: ion fast ignition/capsule perturbation and radiation oncology. Laser-to-beam conversion efficiencies of over 10% are needed for practical applications, and we have already shown inherent efficiencies of >5% from flat foils, on Trident using only a 5th of the intensity [1] and energy of the Nova Petawatt laser [2]. With clever target designs, like structured curved cone targets, we have also been able to achieve major ion energy gains, leading to the highest energy laser-accelerated proton beams in the world [3]. These new target designs promise to help usher in the next generation of particle sources realizing the potential of laser-accelerated beams.

Using a fully kinetic 2D Fokker-Planck model, the generation and evolution of ion density perturbations from nonuniform laser deposition in a plasma slab have been studied. It is found that significant smoothing of the ion density perturbations from nonuniform optically smoothed single beam laser deposition can be achieved on hydrodynamic time scales over a long range of scale sizes. In addition, it is observed that the Fokker-Planck model predicts more smoothing than the hydrodynamic Spitzer model., The original document contains color images.

The Final Proceedings for 24th European Conference on Laser Interaction with Matter, 3June 1996 - 7 June 1996 Inertial Confinement Fusion, Hydrodynamic Instabilities, Coronal Interactions, Physics of High-Density Matter, Radiation Transfer, X-Ray Laser, Short-Pulse Interactions, Laser-Driven Experiments, Laser-Driven Reactor Concepts, and Laser Developments.

The decade of the 1990's is opening for the Gaseous Electronics Conference with precedent setting growth. The technical program comprises 110 oral presentations and 191 poster presentations for a total of 301 papers. The total number of authors are 582. Two timely workshops will be held dealing with: GEC Reference Cell Issues, Comparison Session on High Density Plasma Processing, Other arranged sessions deal with: Particulates in RF Discharges, Cathodes in Discharges: A Review, Electron and Atom Collision Related Phenomena, New and Alternative Applications for Plasma Processing, Ionized Gas Physics in Pulsed Power Applications.