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arXiv · 2010.08598

Evidence for periodic accretion-ejection in LSI+61303

M. Massi·M. Chernyakova·A. Kraus·D. Malyshev·F. Jaron·S. Kiehlmann·S. A. Dzib·R. Sharma·S. Migliari·A. C. S. Readhead
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Abstract

The stellar binary system LS I +61303, composed of a compact object in an eccentric orbit around a B0 Ve star, emits from radio up to gamma-ray energies. The orbital modulation of radio spectral index, X-ray, and GeV gamma-ray data suggests the presence of two peaks. This two-peaked profile is in line with the accretion theory predicting two accretion-ejection events for LS I +61303 along the 26.5 d orbit. However, the existing multiwavelength data are not simultaneous. In this paper, we report the results of a campaign covering radio, X-ray, and gamma-ray observations of the system along one single orbit. Our results confirm the two predicted events along the orbit and in addition show that the positions of radio and gamma-ray peaks are coincident with X-ray dips as expected for radio and gamma-ray emitting ejections depleting the X-ray emitting accretion flow. We discuss future observing strategies for a systematic study of the accretion-ejection physical processes in LS I +61303.

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M. Massi, M. Chernyakova, A. Kraus, D. Malyshev, F. Jaron, S. Kiehlmann, S. A. Dzib, R. Sharma, S. Migliari, A. C. S. Readhead. 2020-10-16. Evidence for periodic accretion-ejection in LSI+61303. https://doi.org/10.1093/mnras%2Fstaa2623

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