As a characteristic feature of generic blazars the polarization behavior of the quasi-periodic optical outbursts observed in OJ287 is investigated. The optical light-curves of the December/2015 outburst are also simulated in terms of the precessing jet nozzle model previously proposed. The polarization behavior of three primary quasi-periodic optical outbursts peaking in 1983.0, 2007.8 and 2015.8 are analyzed in order to understand the nature of their optical radiation. A two-component model has been applied,showing that the variations in flux density, polarization degree and polarization position angle can be consistently interpreted with two polarized components: one steady-component with constant polarization and one burst-component with varying polarization (e.g., relativistic shock propagating along the jet-beam axis). The flux light curves of the December/2015 outburst (including its first flare and second flare) are well model-simulated in terms of 14 elementary synchrotron sub-flares, each having a symmetric profile. The model simulations of polarization behavior for the three major outbursts (in 1983.0, 2007.8 and 2015.8) demonstrate that they all exhibit rapid and large rotations in polarization position angle, implying that they are synchrotron flares produced in the jet. Combining with the results previously obtained for interpreting the optical light curves in terms of lighthouse effect for both quasi-periodic and non-periodic outbursts, we suggest that relativistic jet models may be the most appropriate models for understanding the nature of the optical flaring radiation in blazar OJ287: its optical outbursts may comprise a number of blended "elementary synchrotron flares" , each produced by the helical motion of individual superluminal optical knots via lighhouse effect.
MOMO VI: Multifrequency radio variability of the blazar OJ 287 from 2015-2022, absence of predicted 2021 precursor-flare activity, and a new binary interpretation of the 2016/2017 outburst
A Polarization Study of 3 Blazars using the uGMRT at ~600 MHz
我们目前的结果，从我们的无线电偏振研究与升级的巨型米波射电望远镜（uGMRT）在波段4（550-850 MHz）的3个耀变体：射电大声类星体3C390.3，4C71.07和BL Lac对象1 ES 2344+514。本研究的目的是（一）进行可行性研究波段4偏振与uGMRT，（二）比较和对比的kpc尺度的blazar子类之间的偏振特性。我们在所有三个源中都检测到了线性偏振。两个类星体核心的线偏振度高于BL Lac天体，这与在耀变体秒差距尺度上观察到的类似差异一致。在3C390.3的热点区域观察到15%的最高分数极化，这也显示出扩展的极化瓣结构。1 ES 2344+514显示了核-晕结构，而4C71.07仍然未被解析。沿3C390.3的北部热点和1 ES 2344+514的核心的极化电矢量的旋转，建议射流弯曲。与北叶相比，3C390.3南叶的去极化更大，表明存在“Laing-Garrington效应”。多频率uGMRT极化数据正在进行中，以研究这些源的kpc尺度旋转测量，以寻找周围介质的差异。
Impact of seeing and host galaxy into the analysis of photo-polarimetric microvariability in blazars - Case study of the nearby blazars 1ES 1959+650 and HB89 2201+044
耀变体是一种活动星系核，其喷流在视线附近呈现出特定的方向。因此，它们的辐射是相对论性的，引起极端的行为，特别是在非常短的时间尺度上的强烈变化（即，微变异性）。在这里，我们提出了两个相对较近的耀变体，1 ES 1959+650和HB 89 2201+044，这是使用安装在2.2米望远镜在Calar Alto，西班牙的Calar Alto微弱对象摄谱仪获得的同时测光和偏振观测。这两个耀变体的一个突出特点是存在清晰的宿主星系。这个特殊的特征使我们能够研究它们的内在偏振，测量不受宿主星系影响的星系核的偏振状态。为了进行这项工作，我们计算了光度通量，从中我们计算了耀变体偏振的程度和方向。然后，我们分析了由宿主星系引入的去极化效应，其主要目标是恢复星系核的固有极化，仔细考虑了由观测夜晚的变化引入的虚假极化变化。我们发现，这两个耀变体不存在夜间光偏振变化，虽然我们确实检测到一个显着的夜间变化。比较考虑宿主星系前后的偏振值，我们观察到1 ES 1959+650的偏振度约为1%，HB 89 2201+044的偏振度约为0.3%，从而证明了宿主星系引入的不可忽略的影响。我们注意到，这种宿主星系效应依赖于织带，并随着视宁度的变化而变化，因此在研究耀变体中的频变偏振时应特别考虑。
Constraints on the optical polarization source in the luminous non-blazar quasar 3C 323.1 (PG 1545+210) from the photometric and polarimetric variability
