Unveiling the super-orbital modulation of LS I +61 303 in X-rays
Abstract
From the longest monitoring of LS I +61 303 done to date by the Rossi X-ray Timing Explorer (RXTE) we found evidence for the long-sought, years- long modulation in the X-ray emission of the source. The time evolution of the modulated fraction in the orbital lightcurves can be well fitted with a sinusoidal function having a super-orbital period of 1667 days, the same as the one reported in non-contemporaneous radio measurements. However, we have found a 281.8 \pm 44.6 days shift between the super-orbital variability found at radio frequencies extrapolated to the observation time of our campaign and what we found in the super-orbital modulation of the modulated fraction of our X-ray data. We also find a super-orbital modulation in the maximum count rate of the orbital lightcurves, compatible with the former results, including the shift.
Cite
@article{arxiv.1111.7068,
title = {Unveiling the super-orbital modulation of LS I +61 303 in X-rays},
author = {Jian Li and Diego F. Torres and Shu Zhang and Daniela Hadasch and Nanda Rea and G. Andrea Caliandro and Yupeng Chen and Jianmin Wang},
journal= {arXiv preprint arXiv:1111.7068},
year = {2015}
}
Comments
11 pages, 3 figures, 1 table, Accepted to ApJ Letters