Blazar Compton efficiencies: Fermi, external photons and the Sequence
Blazar Compton efficiencies: Fermi, external photons and the Sequence
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布拉扎尔康普顿效率：费米、外部光子和序列
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
M. Peel
中科院分区：
文献类型：
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作者：
J. Gupta;I. Browne;M. Peel
费米-LAT调查提供了大量根据逆康普顿发射强度选择的blazar样本。我们将第一个Fermi-LAT星表与CRATES射电星表进行交叉关联，并利用这个样本来研究blazar伽马射线亮度是否受到外部光子上散射的影响。利用其紧凑射电核心的8.4 GHz通量密度作为喷注功率的替代，我们计算了它们的康普顿效率参数，该参数衡量了喷注将以超相对论电子形式的能量转换为康普顿伽马射线的能力。我们发现BLLac天体和FSRQs的康普顿效率没有明显差异，康普顿效率与同步加速器峰值频率之间也没有反相关关系。这表明，与同步加速器自康普顿过程相比，外部光子的散射在能量上并不重要。这些结果与blazar序列的预测相矛盾。
The Fermi-LAT survey provides a large sample of blazars selected on the strength of their inverse Compton emission. We cross-correlate the first Fermi-LAT catalogue with the CRATES radio catalogue and use this sample to investigate whether blazar gamma-ray luminosities are influenced by the availability of external photons to be up-scattered. Using the 8.4 GHz flux densities of their compact radio cores as a proxy for their jet power, we calculate their Compton Efficiency parameters, which measure the ability of jets to convert power in the form of ultra-relativistic electrons into Compton gamma-rays. We find no clear differences in Compton efficiencies between BL Lac objects and FSRQs and no anti-correlation between Compton efficiency and synchrotron peak frequency. This suggests that the scattering of external photons is energetically unimportant compared to the synchrotron self-Compton process. These results contradict the predictions of the blazar sequence.