Dye stability under excimer-laser pumping

The stability of laser dyes under the excitation of a XeCl-laser (308 nm) has been investigated. The measurements were performed in an oscillator amplifier device where the amplifier was fully satured. This allows the comparison with the theoretical model showing that the main reason for dye degradation is the absorption of photo-products. Results for the most important dyes are presented. Dye stabilities range from 46 (fluorescein 27) to 3.4×10⁴ (QUI) absorption processes per molecule before the dye solution has degraded to 1/2 of its initial energy output.     

Relation between the expansions of an external potential in spherical functions and spheroidal harmonics

Relations between the coefficients of the expansions of external potentials in spherical and spheroidal functions for finite bodies are derived. These formulas have a more compact and convenient form than those obtained by other authors.     

Equivalence of Euclidean and Wightman field theories

A new inversion formula for the Laplace transformation of tempered distributions with supports in the closed positive semiaxis is obtained. The inverse Laplace transform of a tempered distribution is defined by means of a limit of a special distribution constructed from this distribution. The weak spectral condition on the Euclidean Green's functions implies that some of the limits needed for the inversion formula exist for any Euclidean Green's function with an even number of variables. We then prove that the initial Osterwalder-Schrader axioms [1] and the weak spectral condition are equivalent with the Wightman axioms.The research described in this publication was made possible in part by Grant No. 93-011-147 from the Russian Foundation for Basic Research     

Theoretical and experimental investigation of X-ray O- and N-emission spectra of tungsten

The experimental investigation of the O_IIIN_{VI, VII}-emission spectrum of pure tungsten and tungsten in W₂C is carried out. The experimental data are compared with the theoretical calculation of the intensity in the O_IIIN_{VI, VII}-emission spectrum of tungsten. A good agreement is obtained between the theoretical and experimental spectra. The conclusion was drawn, that the earlier published experimental data on the O_IIIN_VI,VII- spectrum of tungsten referred to carbide of tungsten.     

Spectroscopic properties of Nd3+ ion in TbAlO3 single crystals

Growth of terbium aluminate single crystals and investigation of Nd³⁺ ion spectroscopic properties in them are described. Detailed investigation of absorption and luminescence spectra of Nd³⁺ ions in TbAlO₃ at T = 77 and 300°K permits obtainment of a complete diagram of the Stark components energy. The spectral-structural regularities of Nd³⁺ ions in orthoaluminate monocrystals are analyzed. The dependence on interionic distance of the position of the center of gravity of the ground terms of Nd³⁺ ion along with the nephelauxetic shift of ${}^4\text{F}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}$ term of Nd³⁺ ion is investigated.     

Hysteresis in MOS structures based on Hg1−xCdxTe

Measurements have been made on the electrophysical characteristics of H_g1–xCd_xTe MOS structures of n type (E_g = 0.12–0.2 eV) at a working temperature T=77°K.The experimental results indicate that the hysteresis in the voltage-capacitance characteristics VCC of these MOS structures arises from carrier injection and trapping and also from charge transfer in deep centers DC when the voltage on the field electrode is altered.It is found that in the frequency range examined, the VCC hysteresis may alter in magnitude and reverse in sign.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 81–84, November, 1983.