Abstract
In this work, we analyze the X-ray spectral indices of the 245 Fermi-detected blazars. Relations between the γ-ray emission and the X-ray emission are our research focuses. Our analysis shows that: (1) the X-ray spectral indices of the Fermi/LAT-detected-blazars (α X|Fermi ), have similar distributions with those of non-Fermi-detected blazars (α X|non-Fermi ), and the averaged value \(\overline{\alpha_{X|Fermi}}\simeq\overline{\alpha_{X|non\mbox{-}Fermi}}\); (2) X-ray spectral indices are strong anti-correlated with the logarithmic Doppler factors, log(δ)=−(0.27±0.10)α X +(1.09±0.14), with the correlative coefficient R=−0.33, the chance probability P=1.9 %; (3) X-ray spectral indices (α X ) and γ-ray spectral indices (α γ ) show strong anti-correlation, α X =−(0.62±0.11)α γ +(1.91±0.12), R=−0.35, P<0.001 %.
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Acknowledgements
The work is partially supported by the National Natural Science Foundation of China (NSFC 10633010, NSFC 11173009), Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (GDUPS) (2009), Yangcheng Scholar Funded Scheme (10A027S), and the financial support for the Key subject of Guangzhou City.
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Yuan, Y., Fan, J. X-ray spectral indices of the Fermi/LAT blazars. Astrophys Space Sci 352, 207–214 (2014). https://doi.org/10.1007/s10509-014-1878-y
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DOI: https://doi.org/10.1007/s10509-014-1878-y