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arXiv · 1803.01854

Hour time-scale QPOs in the X-ray and radio emission of LS I +61$^{\circ}$303

Silvia Nösel·Richa Sharma·Maria Massi·Giuseppe Cimò·Masha Chernyakova
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Abstract

LS I +61$^{\circ}$303 is an X-ray binary with a radio outburst every ~27 days. Previous studies of the stellar system revealed radio microflares superimposed on the large radio outburst. We present here new radio observations of LS I +61$^{\circ}$303 at 2.2 GHz with the Westerbork Synthesis Radio Telescope (WSRT). Using various timing analysis methods we find significant Quasi-Periodic Oscillations (QPOs) of 55 minutes stable over the duration of 4 days. We also use archival data obtained from the Suzaku satellite at X-ray wavelengths. We report here for the first time significant X-ray QPOs of about 2 hours present over the time span of 21 hours. We compare our results with the previously reported QPO observations and we conclude that the QPOs seem to be associated with the radio outburst, independent of the amplitude of the outburst. Finally, the different QPO time-scales are discussed in the context of magnetic reconnection.

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Silvia Nösel, Richa Sharma, Maria Massi, Giuseppe Cimò, Masha Chernyakova. 2018-03-05. Hour time-scale QPOs in the X-ray and radio emission of LS I +61$^{\circ}$303. https://doi.org/10.1093/mnras%2Fsty417

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