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[en] This review is concerned with fundamental developments or advances in x-ray spectrometry and does not cover the thousands of publications arising from applications of x-ray techniques. The review is divided into parts entitled: excitation, dispersion and detection, instrumentation and techniques, quantitative analysis, and conclusions. 162 references are cited
[en] There is currently not only keen interest in accurate spectroscopy of one- and two-electron ions but also the by now well-founded hope that these spectra can be produced under conditions where Doppler and spectator electron problems are under adequate control. These developments will require that we confront problems of wavelength normalization at a more refined level than has been necessary in the past. This report briefly outlines the present-day situation in the case of using normal X-ray lines as references and the steps which might be taken to transcend limitations inherent in this approach. (orig.)
[en] The incident beam monochromatization technique for the separation of Ksub(α1) and Ksub(α2) components in X-ray line profile analysis is described. The monochromatization is performed in two steps: First, using a single bent Johansson type quartz crystal (2 R = 500 mm) the Cu Ksub(α)-doublet radiation is dispersed and then the separation is made by placing a narrow slit (0.07 mm) in the position of the Cu Ksub(α1) rays on the Rowland circle. In this experimental condition the intensity ratio of the Cu Ksub(α2) to the Cu Ksub(α1) is reduced to less than 0.5%. This value is small enough for a quantiative X-ray line profile analysis so that the analytical separation is unnecessary. (orig.)
[en] We present the results of spectral analysis of a sample of RS CVn stars observed with the EXOSAT Observatory. Data from both the Medium Energy and Low Energy experiments are analysed assuming simple spectral models (one-temperature, two-temperature, continuous emission measure distribution models). We investigate the dependence of the fitted coronal parameters on the signal-to-noise ratio and the instrument response function, and compare the results with those previously obtained by the Einstein IPC and SSS experiments. We find evidence for multi-temperature coronal structures in RS CVn stars as well as indications of intrinsic differences in the temperature stratification of different stars. The simple power law EM ∼ Tα assumed by us for the continuous emission measure distribution appears to be inconsistent with several of our observations. For the others, we derive power law indices α that are higher than those found for solar coronal loops and interpret this as evidence that the coronae of RS CVn binaries involve structures different from those typically observed on the Sun
[en] Arrays of silicon sensors can be utilized in those spectroscopic applications where a high event throughput is needed, for example in synchrotron-based experiments. Yet, in such arrays several noise contributions, beyond the well-known leakage, thermal and flicker noises, can be present which are absent in single channel detectors. Additional noise is generated ultimately by the condition at the silicon/silicon oxide interface, which in turn depends on the parameters of the silicon oxide over the not-implanted gaps. We discuss how to control this region to obtain the best spectroscopic performances.