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Evidence of H alpha periodicities in LS I+61303

R. K. Zamanov·J. Marti·J. M. Paredes·J. Fabregat·M. Ribo·A. E. Tarasov
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Abstract

We present the results of analyzing H$α$ spectra of the radio emitting X-ray binary LS I+61303. For the first time, the same 26.5 d radio period is clearly detected in the H$α$ emission line. Moreover, the equivalent width and the peak separation of the H$α$ emission line seem also to vary over a time scale of 1600 days. This points towards the $\sim4$ yr modulation, detected in the radio outburst amplitude, being probably a result of variations in the mass loss rate of the Be star and/or density variability in the circumstellar disk. In addition, the dependence of the peak separation from the equivalent width informs us that the LS I+61303 circumstellar disk is among the densest of Be-stars.

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R. K. Zamanov, J. Marti, J. M. Paredes, J. Fabregat, M. Ribo, A. E. Tarasov. 1999-09-14. Evidence of H alpha periodicities in LS I+61303. https://arxiv.org/abs/astro-ph/9909233

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