We present the results of the X-ray flaring activity of 1ES 1959+650 during 2017 October 25–26 using AstroSat observations. The source was variable in the X-ray. We investigated the evolution of the X-ray spectral properties of the source by dividing the total observation period (∼130 ks) into time segments of 5 ks, and fitting the Soft X-ray focusing Telescope and Large Area X-ray Proportional Counter spectra for each segment. Synchrotron emission of a broken power-law particle density model provided a better fit than the log-parabola one. The X-ray flux and the normalized particle density at an energy less than the break one were found to anticorrelate with the index before the break. However, a stronger correlation between the density and index was obtained when a delay of ∼60 ks was introduced. The amplitude of the normalized particle density variation |Δnγ/nγ| ∼ 0.1 was found to be less than that of the index ΔΓ ∼ 0.5. We model the amplitudes and the time delay in a scenario where the particle acceleration time-scale varies on a time-scale comparable to itself. In this framework, the rest-frame acceleration time-scale is estimated to be ∼1.97 × 105 s and the emission region size to be ∼6.73 × 1015 cm.

中文翻译：

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AstroSat 在 2017 年 10 月燃烧期间对 HBL 1ES 1959+650 的观测

我们使用 AstroSat 观测展示了 2017 年 10 月 25 日至 26 日期间 1ES 1959+650 的 X 射线耀斑活动的结果。源在 X 射线中是可变的。我们通过将总观测周期（~130 ks）划分为 5 ks 的时间段，并拟合软 X 射线聚焦望远镜和大面积 X 射线比例计数器光谱，研究了源 X 射线光谱特性的演变对于每个段。破坏幂律粒子密度模型的同步加速器发射提供了比对数抛物线模型更好的拟合。X 射线通量和能量小于断裂能量的归一化粒子密度与断裂前的指数呈反相关。然而，当引入~60 ks 的延迟时，密度和指数之间的相关性更强。归一化粒子密度变化幅度|Δnγ/nγ| 发现~0.1小于指数ΔΓ~0.5的值。我们在粒子加速时间尺度在与其自身相当的时间尺度上变化的情况下对幅度和时间延迟进行建模。在这个框架中，静止帧加速时间尺度估计为~1.97×105 s，发射区域大小为~6.73×1015 cm。