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Abstract. The Space Telescope Imaging Spectrograph (STIS) on HST provides the first ultraviolet data that are of sufficient spectral and temporal resolution to generate Doppler tomograms of X-ray binaries. We show both optical and ultraviolet maps constructed for the intermediate mass system Hercules X-1/HZ Her and the massive wind-fed system SMC X-1/SK160. We have used the maps and corresponding lightcurves as diagnostics with which to test the validity of published models for Hercules X-1. We find that although the models are mostly able to explain the light curves they are not consistent with the full phase maps. We present simulations of Doppler maps of X-ray lines that will be possible with the spectral and temporal resolution and substantial effective area of the next major X-ray mission, Con-X.

Studies of the crystal optics, dielectric properties from 10 Hz to 10 kHz, and the electro-optical properties of crystalline argon, grown with a modified Bridgman technique, are reported. The optical character of the solids was examined using polarized light, with varying crystal growth parameters, viz., rate, annealing, and pressure. Using crossed polaroids to examine the transparent crystals, three basic kinds of optical regions were observed: optically isotropic, optically anisotropic (birefringent), and sharp, horizontal, alternate isotropic and anisotropic striations. Low-order strain birefringence with broad and diffuse patterns is also described. The observations are considered in terms of impurity segregation and strain effects and it is concluded, with support from annealing and electro-optic studies up to 40 kV/cm, that the birefringent regions have hcp structure and the isotropic regions have fcc structure. The dielectric constant (ε) was directly measured for solid argon between two concentric stainless-steel cylinders in a three-terminal network that minimized stray fields. It was found that ε = 1.586 over the entire frequency range with an estimated experimental error of 2%. Variation of ε with growth rate and annealing qualitatively supports the optical observations on hcp and fcc structure.

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