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A magneto-optic Faraday rotation diagnostic was implemented on a Z-pinch driven flux-compression generator to measure line-averaged, megagauss, axial-magnetic fields up to 1.6 MG with rise times of 30 kG/ns. The axial-magnetic field rotated the plane of polarization of a 2-W argon laser beam in a 0.725-mm-diam, fused silica quartz fiber mounted coaxial with the Z pinch. The rapid rise time and the high radiation environment presented by the Z-pinch plasma caused a high-pressure impulse <100 kbar, to be coupled into the quartz-fiber probe disrupting the polarization-preserving properties of the fiber. The time scale for disruption was characteristic of a shock propagating radially through the fiber to its core. This paper will describe the response of the Faraday diagnostic under these conditions and present a simple model that describes the effects of fiber depolarization that is consistent with previous observations of stress-induced depolarization in optical fibers. [ABSTRACT FROM AUTHOR]

Studies the formation of stable and highly resistive anodic oxides on indium phosphide (InP). Potential applications of anodic oxidation of InP; Overview of the experiment; Properties of the anodic oxides.

Presents a study that investigated magnetic fields produced in a gas-puff Z pinch. Description of the models; Experimental apparatus used in the study; Results; Discussion.

Abstract: We have developed simple single pixel thermopile infrared (IR) detectors for monitoring clouds for the purpose of atmospheric research and for cloud detection over astronomical and astrophysical observatories. Those detectors were developed with 3° and 90° fields of view (FOV) and have a broad spectral response extended from 5.5μm to above 20μm centered on a wavelength of 10μm. This paper aims to give a detailed description of these detectors, and the methodology followed to construct and calibrate them. Results from observations with these detectors will be given. Simulations using MODTRAN software were carried out to examine the theoretical expectation of the measured IR sky temperatures by these detectors. Good agreements between the measured and simulated data were found. [Copyright &y& Elsevier]

The imploding plasma column of a gas-puff Z pinch was used to compress an embedded axial magnetic field. Field compression ratios up to 180 times and peak compressed fields up to 1.6 MG were measured by Faraday rotation. Field compression by this method has the advantage of high repetition rate for applications in the controlled production of high-energy densities, solid-state studies, generation of short-wavelength radiation, reducing the ignition threshold for fusion, and particle acceleration. [ABSTRACT FROM AUTHOR]

Abstract: We present an analysis technique that uses the timing information of Cherenkov images from extensive air showers (EAS). Our emphasis is on distant, or large core distance γ-ray induced showers at multi-TeV energies. Specifically, combining pixel timing information with an improved direction reconstruction algorithm, leads to improvements in angular and core resolution as large as ∼40% and ∼30%, respectively, when compared with the same algorithm without the use of timing. Above 10TeV, this results in an angular resolution approaching 0.05°, together with a core resolution better than ∼15m. The off-axis post-cut γ-ray acceptance is energy dependent and its full width at half maximum ranges from 4° to 8°. For shower directions that are up to ∼6° off-axis, the angular resolution achieved by using timing information is comparable, around 100TeV, to the on-axis angular resolution. The telescope specifications and layout we describe here are geared towards energies above 10TeV. However, the methods can in principle be applied to other energies, given suitable telescope parameters. The 5-telescope cell investigated in this study could initially pave the way for a larger array of sparsely spaced telescopes in an effort to push the collection area to >10km2. These results highlight the potential of a ‘sparse array’ approach in effectively opening up the energy range above 10TeV. [Copyright &y& Elsevier]

Abstract: Results in TeV -ray astronomy of recent years (in particular from H.E.S.S.) point to a population of -ray sources at energies . This provides strong impetus for future studies in the multi-TeV energy range. This key energy range addresses the origin of PeV cosmic-rays (CRs) at around the knee energy, and also astrophysical questions associated with multi-TeV -ray production in an increasing variety of environments. Here, we outline the TenTen project—a proposed stereoscopic array of modest-sized (10–) Cherenkov imaging telescopes optimised for the –100TeV range. TenTen telescopes are designed to operate with a wide field of view (– diameter) and the full array is expected to achieve an effective area of at energies above 10TeV. Here, we present a summary of the motivation for TenTen and its key performance parameters. [Copyright &y& Elsevier]