A small megagauss generator which produces 110 T by fast semi-destructive capacitor discharge into a single-turn coil of 10 mm diameter is described. For spectroscopic applications the pulses are adequately resolved by 8 - 12 bit, 200 - 1000 MSa data recording systems. The technical implementation of the 60 kV discharge circuit with a total inductance of less than 26 nH, not including the field coil, is discussed in detail. The performance is characterized in terms of the oscillatory circuit parameters R, L and C with brief references to more fundamental studies on transient field phenomena. Safety features as well as the organization and handling of control units and data recording systems are explicitly described to demonstrate the applicability of the generator.

A new technique to determine the depth‐dose function is described using the measurement of the electron beam induced barrier current on bevelled homo p‐n junction structures. A universal depth‐dose function on GaAsP is found in the form \documentclass{article}\pagestyle{empty}\begin{document}$ \Phi (z)\, = \,\Phi _0 \,\exp \,\left[{ - \left({\frac{{z - a}}{{z_0 }}} \right)^2} \right]\,{\rm with}\,z_0 \, = \,\left\{{\begin{array}{*{20}c} {2.3a\,{\rm for}\,z \mathbin{\lower.3ex\hbox{$\buildrel>\over {\smash{\scriptstyle=}\vphantom{_x}}$}} a} \hfill \\ {1.3a\,{\rm for}\,0 \mathbin{\lower.3ex\hbox{$\buildrel<\over {\smash{\scriptstyle=}\vphantom{_x}}$}} \,z\, < \,a} \hfill \\ \end{array}} \right. $\end{document} in the investigated energy range from 10 to 45 keV. The distance of the maximum under the surface can be obtained by the relation a = A0EPr1.65 with A0 = 2.95 × 10−3 (EPr in keV, a in μm).

Thernioelastische und elastische Eigenschaften des tetragonalen QuecksilberdijodidsAlle elastische Konstanten cij und thermoelastische Konstanten T,, = d log c,,/dT (T Temperatur) des tetragonalen HgJ, wurden mit Hilfe von Ultraschallmethoden an Einkristallen gemessen, die aus der Dampfphase mit der Methode der dynamischen Gradientenumkehr gezuchtet worden waren. HgJ, weist starke elastische AnisotropieEffekte auf, die sich qualitativ aus der Struktur deuten lassen. Die Temperaturabhiingigkeit der elastischen Konstanten ist geringer als erwartet. Lediglich die sehr kleine Scherkonstante cg6 sinkt betriichtlich mit wachsender Temperatur. Dieses Verhalten durfte rnit der bekannten Phasenumwandlung bei 126 "C zusammenhiingen. elastic constants ci, and thermoelastic constants T,, = d log c,,/d T ( T temperature)of tetragonal HgI, have been measured by ultrasonic methods on single crystals which had been grown from the vapour phase by the method of dynamical gradient reversal. HgI, exhibits strong anisotropic elastic properties which are qualitatively explained by structural details. The temperature dependence of the elastic constants is smaller than expected. Only the very small shear constant c16 is strongly decreasing with increasing temperature. This behaviour might be seen in connection with the known phase transition at about 126 "C.

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