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Echo Tomography of Sco X-1 using Bowen Fluorescence Lines

J. Casares·T. Muñoz-Darias·I. G. Martinez-Pais·R. Cornelisse·P. A. Charles·T. R. Marsh·V. S. Dhillon·D. Steeghs
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Abstract

We present preliminary results of a simultaneous X-ray/optical campaign of the prototypical LMXB Sco X-1 at 1-10 Hz time resolution. Lightcurves of the high excitation Bowen/HeII emission lines were obtained through narrow interference filters with ULTRACAM, and these were cross-correlated with X-ray lightcurves. We find evidence for correlated variability, in particular when Sco X-1 enters the Flaring Branch. The Bowen/HeII lightcurves lag the X-ray lightcurves with a light travel time which is consistent with reprocessing in the companion star.

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J. Casares, T. Muñoz-Darias, I. G. Martinez-Pais, R. Cornelisse, P. A. Charles, T. R. Marsh, V. S. Dhillon, D. Steeghs. 2005-03-03. Echo Tomography of Sco X-1 using Bowen Fluorescence Lines. https://doi.org/10.1063/1.2130255

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