In this paper, we present the timing and spectral results for the seven distant and poorly investigated BL Lacertae sources with redshifts z ≳ 0.5 $z\gtrsim 0.5$ , using the archival data obtained with the Swift and other multifrequency instruments during 2006 August–2015 July. Our timing study has revealed a number of the 0.3–10 keV flux changes from the fluctuations observed within one day to the variabilities on timescales of a few months. Namely, the relatively densely-sampled observations of BZB J1517+6525 showed a strong X-ray flare by a factor of ∼5 during 2014 September-December. While this instance can be explained by the propagation of shock wave though the blazar jet which causes a strong heat-up of the relativistic plasma, the lower-amplitude flux fluctuations observed in higher X-ray states could be related to the interaction between the shock front and jet inhomogeneities. The curved 0.3–10 keV spectra showed the ranges of the photon index at 1 keV a = 1.27 $a=1.27$ (0.10)–2.30(0.09), curvature parameter b = 0.12 $b = 0.12$ (0.08)–1.19(0.27), synchrotron SED peak position E p = 0.49 $E_{p} = 0.49$ (0.09)–3.39(0.97) keV, while some spectra do not exhibit spectral curvature and fit well with a simple power law model yielding the 0.3–10 keV photon-index Γ = 1.48 $\Gamma =1.48$ (0.15)–2.32(0.08). Large spectral curvatures observed for the majority of the log-parabolic spectra hint at the importance of the second-order Fermi mechanism for our targets. Our targets show very high isotropic luminosity L 0.3 – 10 keV ∼ 10 46 erg s − 1 $L_{0.3\text{--}10~\text{keV}}\sim 10^{46}~\mbox{erg}\,\mbox{s}^{-1}$ compared to the nearby bright BL Lacertae objects.

中文翻译：

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对远处高能峰值BL Lacertae天体的快速观测

在本文中，我们使用 2006 年 8 月至 2015 年期间使用 Swift 和其他多频仪器获得的档案数据，展示了红移 z ≳ 0.5 $z\gtrsim 0.5$ 的七个遥远且研究不足的 BL Lacertae 源的时序和光谱结果七月。我们的时间研究揭示了从一天内观察到的波动到几个月时间尺度上的变化，0.3-10 keV 的通量变化。也就是说，BZB J1517+6525 的相对密集采样观测显示，在 2014 年 9 月至 12 月期间，强烈的 X 射线耀斑约为 5 倍。虽然这种情况可以通过冲击波通过耀变体射流的传播来解释，这会导致相对论等离子体强烈升温，在较高 X 射线状态下观察到的较低幅度通量波动可能与激波前缘和射流不均匀性之间的相互作用有关。弯曲的 0.3-10 keV 光谱显示了 1 keV 处的光子指数范围 a = 1.27 $a=1.27$ (0.10)–2.30(0.09)，曲率参数 b = 0.12 $b = 0.12$ (0.08)–1.19( 0.27)，同步加速器 SED 峰值位置 E p = 0.49 $E_{p} = 0.49$ (0.09)–3.39(0.97) keV，而一些光谱没有表现出光谱曲率，并且与简单的幂律模型拟合得很好，产生了 0.3– 10 keV 光子指数 Γ = 1.48 $\Gamma =1.48$ (0.15)–2.32(0.08)。在大多数对数抛物线光谱中观察到的大光谱曲率暗示了二阶费米机制对我们目标的重要性。我们的目标显示出非常高的各向同性光度 L 0.3 – 10 keV ∼ 10 46 erg s − 1 $L_{0.