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arXiv · 1311.7618

Connection between orbital modulation of H-alpha and gamma-rays in the Be/X-ray binary LSI+61303

R. Zamanov·J. Martí·K. Stoyanov·A. Borissova·N. A. Tomov
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Abstract

We studied the average orbital modulation of various parameters (gamma-ray flux, H-alpha emission line, optical V band brightness) of the radio- and gamma-ray emitting Be/X-ray binary LSI+61303. Using the Spearman rank correlation test, we found highly significant correlations between the orbital variability of the equivalent width of the blue hump of the H-alpha and Fermi-LAT flux with a Spearman p-value 2e-5, and the equivalent widths ratio EW_B/EW_R and Fermi-LAT flux with p-value 9e-5. We also found a significant anti-correlation between Fermi-LAT flux and V band magnitude with p-value 7.10^{-4}. All these correlations refer to the average orbital variability, and we conclude that the H-alpha and gamma-ray emission processes in LSI+61303 are connected. The possible physical scenario is briefly discussed.

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R. Zamanov, J. Martí, K. Stoyanov, A. Borissova, N. A. Tomov. 2013-11-29. Connection between orbital modulation of H-alpha and gamma-rays in the Be/X-ray binary LSI+61303. https://doi.org/10.1051/0004-6361/201322936

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