论文标题
2015 - 2017年OJ 287活动的多波长视图：光谱变化对中央引擎模型和MEV-GEV发射机制的影响
A Multi-wavelength View of OJ 287 Activity in 2015-2017: Implications of Spectral Changes on Central-engine Models and MeV-GeV Emission Mechanism
论文作者
论文摘要
整个观察领域的各种特性范围使OJ 287成为相对论喷射和增生物理学问题的最爆炸性的BL LAC对象之一，以及强烈的重力理论。在这里，我们简要汇编了文献的观察结果以及广泛研究的推论/见解，但着重于对其$ \ sim $ 12年qpoos和高能量排放机制的解释。一个模型中的QPOO归因于与二进制SMBH的动力学相关的磁盘影响，而替代模型则将其归因于与单射流或双喷射的进动有关的几何效应。我们讨论了在2015---2017多波长高活性中报道的新光谱特征的含义 - 在两者的上下文中，NIR光谱频谱的中断和MEV-GEV发射的硬化以及其峰位置的变化。 The reported NIR-optical break nicely fits the description of a standard accretion disk emission from an SMBH of mass $\sim~10^{10}~M_\odot$ while the time of its first appearance in end-May 2013 (MJD 56439) is in close coincidence with the time of impact predicted by the disk-impact binary SMBH model.这种与磁盘影响二进制SMBH模型的模型参数的光谱和时间巧合提供了独立的证据，有利于该模型，而不是几何模型，该模型认为总中央发动机质量在$ \ rm 10^{7-9} 〜M_ m_ \ odot $之间。另一方面，MEV-GEV光谱变化自然是通过从宽线区域的光子反向散射的，与在准周期爆发的先前循环中检测到宽发射线的一致。结合以前的SED研究表明，在OJ 287中，MEV-GEV发射是由外部组合产生的。
A diverse range of peculiar properties across the domains of observation have made OJ 287 one of the best-explored BL Lac objects on the issues of relativistic jets and accretion physics as well as the strong theory of gravity. We here present a brief compilation of observational results from the literature and inferences/insights from the extensive studies but focus on the interpretation of its $\sim$ 12-yr QPOOs and high energy emission mechanisms. The QPOOs in one model are attributed to the disk-impact related to dynamics of the binary SMBHs while alternative models attribute it to the geometrical effect related to the precession of a single jet or double jets. We discuss implications of the new spectral features reported during the 2015--2017 multi-wavelength high activity of the source -- a break in the NIR-optical spectrum and hardening of the MeV-GeV emission accompanied by a shift in the location of its peak, in the context of the two. The reported NIR-optical break nicely fits the description of a standard accretion disk emission from an SMBH of mass $\sim~10^{10}~M_\odot$ while the time of its first appearance in end-May 2013 (MJD 56439) is in close coincidence with the time of impact predicted by the disk-impact binary SMBH model. This spectral and temporal coincidence with the model parameters of the disk-impact binary SMBH model provides independent evidence in favor of the model over the geometrical models which argue a total central-engine mass in the range of $\rm 10^{7-9}~M_\odot$. On the other hand, the MeV-GeV spectral change is naturally reproduced by the inverse Compton scattering of photons from the broad-line region and is consistent with the detection of broad emission lines during the previous cycles of quasi-periodic outbursts. Combining this with previous SED studies suggests that in OJ 287, MeV-GeV emission results from external Comptonization.
