EXOSAT Medium Energy Observations of CYG X-2 Spectra and QPOs
نویسندگان
چکیده
منابع مشابه
The Soft and Medium–energy X–ray Variability of Ngc 5548: a Reanalysis of Exosat Observations
We present a detailed cross–correlation (CCF) and power spectrum re–analysis of the X–ray light curves of the bright Seyfert 1 galaxy NGC5548 obtained with EXOSAT. The 0.05–2 keV and 1–4 keV light curves are cross–correlated with the 1–9 keV and 4–9 keV light curves respectively. We discuss how spurious time lags can be introduced by systematic effects related to detector swapping as well as th...
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High resolution X-ray absorption spectroscopy is a powerful diagnostic tool for probing chemical and physical properties of the interstellar medium (ISM) at various phases. We present detections of K transition absorption lines from the low ionization ions of O I, O II, Ne I, Ne II, and Ne III, and the high ionization ones of O VI, O VII, O VIII, Ne IX, and Mg XI, as well as details of neutral ...
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The spectra of disc accreting neutron stars generally show complex curvature, and individual components from the disc, boundary layer and neutron star surface cannot be uniquely identified. Here we show that much of the confusion over the spectral form derives from inadequate approximations for comptonization and for the iron line. There is an intrinsic low energy cutoff in comptonised spectra ...
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ژورنال
عنوان ژورنال: International Astronomical Union Colloquium
سال: 1987
ISSN: 0252-9211
DOI: 10.1017/s025292110010555x