Abstract
Using γ-ray band data detected by Fermi Large Area Telescope (LAT) and X-ray band data for 78 blazars, we find a medium correlation between X-ray flux and γ-ray flux in all states. A medium correlation is also found between X-ray (1 keV) mean spectral index α x and γ-ray mean spectral index α γ for BL Lacertae objects (BL Lacs), and there is no correlation for Flat Spectrum Radio Quasars (FSRQs). From these results, we suggest that the most likely radiation mechanism for the high energy gamma-rays would be synchrotron self-Compton (SSC), and that the gamma-ray emission mechanism may be somewhat different for BL Lacs and FSRQs.
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Acknowledgements
We thank the anonymous referee for valuable comments and suggestions. We are very grateful to the Science Foundation of Yunnan Province of China. This work is supported by the National Nature Science Foundation of China (11163007, U1231203) and the Program for Innovative Research Team (in Science and Technology) in Yunnan Province.
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Li, B., Zhang, H., Zhang, X. et al. Correlation between X-ray and γ-ray for Fermi blazars. Astrophys Space Sci 347, 349–355 (2013). https://doi.org/10.1007/s10509-013-1521-3
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DOI: https://doi.org/10.1007/s10509-013-1521-3