Insights into the accretion flow in QS Telescopii (RE1938-461) from HST observations
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چکیده
We present HST/FOS observations of the polar QS Tel (RE1938-461) revealing new details in its 140min UV orbital variability. A colour-dependent continuum orbital modulation as well as a narrow dip in its light curve, occurring at the same orbital phases as the one detected in the EUVE band, are observed. Their spectral dependence allows us to identify the heated regions of thewhite dwarf surfacewith complex structure and temperature gradients as well as the accretion stream. The absorption dip occurs during the minimum of UV emission line light curves and is interpreted as the occultation of the heated spot on the white dwarf surface by the accretion stream.We also confirm the strong UV modulation of the emission lines which, in these high time resolved spectroscopic data, is structured and consistent with X-ray irradiation of the stream material.
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تاریخ انتشار 1997