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Megagauss-level magnetic fields were predicted theoretically and observed experimentally. The field generation due to resonance absorption of laser light and thermoelectric currents is discussed. An experiment to measure these fields by Faraday rotation of light (2660A) is described. (auth)

A semiconductor detector x-ray spectrometer has been constructed for the analysis of elements in air particulate specimens. The excitation radiation is provided, either directly or indirectly, using a low power (40 watts) Ag anode x- ray tube. Less than 100 ng for most of the elements in the range Mg $Yields$ Zr, Pb are easily detected within two 1-minute counting intervals. A calibration technique for light element analysis and an experimental method which compensates for particle size effects are discussed. (auth)

Several techniques for using direct electron-pumping of gas lasers are reviewed. The primary objective is to categorize pump geometries and to give guidelines for gun selection and pulser design. Examples and application of pump technology are given. (auth)

Far infrared Fourier transform spectroscopy was used to study the low lying vibronic states of Mn$sup 3+$ in Al$sub 2$O$sub 3$ and the plasma absorption of electron-hole droplets in Ge. The transmission of Mn-doped samples of Al$sub 2$O$sub 3$ was measured in the frequency range from 3 to 30 cm$sup -1$ in applied magnetic fields up to 50 kG. Absorption lines were observed due to both ground and excited state transitions. Polarization measurements established that these absorption lines were due to electric dipole transitions. Temperature dependence measurements were used to derive a level diagram for the low lying states of Mn$sup 3+$. A phenomenological model based on an electronic Hamiltonian was developed which successfully describes the data. The empirically determined trigonal field and spin-orbit quenching parameters of this model are 0.7 and 0.1 respectively. This quenching is attributed to the dynamic Jahn-- Teller interaction. The plasma absorption of small ($alpha$) electron-hole drops in Ge was measured in the frequency range from 30 to 300 cm$sup -1$. The observed absorption is in good agreement with measurements by Vavilov and other workers. A theoretical model which includes both intraband and interband contributions to the dielectric constant in the Rayleigh limit of Mie …

A target chamber for application in the laser fusion program must satisfy some very basic requirements. (1) Provide a vacuum on the order of 10$sup -6$ torr. (2) Support a microscopically small target in a fixed point in space and verify its location within 5 micrometers. (3) Contain an adjustable beam focusing system capable of delivering a number of laser beams onto the target simultaneously, both in time and space. (4) Provide access for diagnostics to evaluate the results of target irradiation. (5) Have flexibility to allow changes in targets, focusing optics and number of beams. The ARGUS laser which is now under construction at LLL will have a target chamber which meets these requirements in a simple economic manner. The chamber and auxiliary equipment are described, with reference to two double beam focusing systems; namely, lenses and ellipsoidal mirrors. Provision is made for future operation with four beams, using ellipsoidal mirrors for two-sided illumination and lens systems for tetragonal and tetrahedral irradiation. (auth)

A cryopumping module using metallic surfaces at liquid helium temperature for condensation of hydrogen and deuterium gas has been constructed. This pump, a prototype of four units which will provide pumping for the Livermore 200 kV test stand, will be used to verify the concept and establish engineering parameters. Upon completion of engineering tests and evaluation the pump will be installed in an operating beam line. The design point pumping capacity is 80,000 liters per second for hydrogen and deuterium at 10$sup -4$ torr based on sticking coefficients of 0.15 and 0.25, respectively. Both the liquid helium temperature pumping surface and the liquid nitrogen temperature radiation shields are constructed of quilted double wall cylindrical shells. The pumping shell dimensions are 1.5 meters dia. x 0.6 meters long. Cryogen circulation is convection current driven in both cases. Liquid helium is supplied from an overhead Dewar through bayonet coupling. In the 200 kV beam line, pumping modules will be supplied via transfer lines from a central Dewar. Voltage standoff will be accomplished in the transfer lines. (auth)

Isentropic compression of laser fusion targets requires highly uniform illumination over the entire target surface, and near normal incidence. For a two beam laser, this is best achieved using a fast catadioptric system. In designing such a system, the total thickness of refracting material must be minimized, to avoid loss of optical quality through small scale self focusing. Such a system is being fabricated for use with the ARGUS laser. It consists of a pair of nested ellipsoidal reflectors, coupled with an aspheric doublet refracting element which provides uniform illumination for the specified laser beam profile. (auth)

An optimal energy delivery system for the world's largest glass laser system has been designed based on computer modeling and operation of laser hardware. Components of the system have been tested on operating lasers at LLL. The Shiva system is now under construction and will be completed in 1977. The energy supply described here will provide cost-effective, reliable power and facilitate the gathering of data in pursuit of controlled thermonuclear reactions. (auth)

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