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arXiv · 1210.6180

Unveiling the super-orbital modulation of LSI +61 303 in X-rays

Jian Li·Diego F. Torres·Shu Zhang·Daniela Hadasch·Nanda Rea·G. Andrea Caliandro·Yupeng Chen·Jianmin Wang
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Abstract

We found evidence for the super-orbital modulation in the X-ray emission of LS I +61 303 from the longest monitoring date by the RXTE. The time evolution of the modulated fraction in the orbital light curves can be well fitted with a sinusoidal function having a super-orbital period of 1667 days. However, we have found a 281.8+/-44.6 day shift between the super-orbital variability found at radio frequencies and our X-ray data. We also find a super-orbital modulation in the maximum count rate of the orbital light curves, compatible with the former results, including the shift.

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Jian Li, Diego F. Torres, Shu Zhang, Daniela Hadasch, Nanda Rea, G. Andrea Caliandro, Yupeng Chen, Jianmin Wang. 2012-10-23. Unveiling the super-orbital modulation of LSI +61 303 in X-rays. https://doi.org/10.1017/s1743921312019886

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