Event Horizon Telescope imaging of the archetypal blazar 3C 279 at an extreme 20 microarcsecond resolution
Event Horizon Telescope imaging of the archetypal blazar 3C 279 at an extreme 20 microarcsecond resolution
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事件视界望远镜以 20 微角秒的极限分辨率对原型耀变体 3C 279 进行成像
DOI：
10.1051/0004-6361/202037493
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发表时间：
2020
影响因子：
6.5
通讯作者：
Savolainen
中科院分区：
文献类型：
--
作者：
Kim Jae-Young;Krichbaum Thomas P.;Broderick Avery E.;Wielgus Maciek;Blackburn Lindy;Gomez Jose L.;Johnson Michael D.;Bouman Katherine L.;Chael Andrew;Akiyama Kazunori;Jorstad Svetlana;Marscher Alan P.;Issaoun Sara;Janssen Michael;Chan Chi-kwan;Savolainen
3C 279是一个典型的耀变体，具有突出的射电喷流，在整个电磁波谱中显示出宽带通量密度变化。我们使用超高的角分辨率技术-全球甚长基线干涉测量（VLBI）在1.3毫米（230 GHz）-解决3C 279的最里面的射流，以研究其精细尺度的形态接近射流基地，高度可变的射线发射被认为是起源，根据各种模型。在2017年4月的四天里，使用230 GHz的事件视界望远镜（包括相控的阿塔卡玛大型毫米/亚毫米阵列）以20 μas的角分辨率观测到了这个源（在z = 0：536的红移下，这相当于1700个史瓦西半径，黑洞质量MBH = 8 × 108 M）。成像和模型拟合技术应用于数据参数化的细尺度源结构及其variation.We发现一个多成分的内部射流形态与最北的组件延长垂直于射流的方向，在较长的波长成像。在所有四个观察日以及不同的成像方法和模型拟合技术中，细长的核结构是一致的，因此看起来很稳健。由于它的致密性和亮度，我们把北方核结构称为VLBI“核”。这种形态可以被解释为一个广泛的解决射流基地或空间上弯曲的jet.We还发现显着的一天到一天的变化，在关闭阶段，这似乎最明显的三角形与最长的基线。我们的分析表明，这种变化与源结构的系统性变化有关。两个内部喷流分量以1.15c和1.20c的视速度（分别为1.1：3和1.1：7 μas day-1）非径向移动，这更有力地支持了弯曲、可能旋转的喷流中的行进激波或不稳定性的假设。观测到的表观速度也与3C 279在较长波长（cm）下观测到的大尺度喷流运动学一致，表明1.3 mm核心和外部喷流之间没有明显的喷流加速。喷流成分的本征亮度温度≤1010 K，比在≥ 7 mm波长处看到的典型值低一个量级或更多。低亮度温度和形态复杂性表明，3C 279的核心区域在短波长（mm）下变得光学薄。© J. - Y. Kim et al. 2020.
3C 279 is an archetypal blazar with a prominent radio jet that show broadband flux density variability across the entire electromagnetic spectrum. We use an ultra-high angular resolution technique - global Very Long Baseline Interferometry (VLBI) at 1.3mm (230 GHz) - to resolve the innermost jet of 3C 279 in order to study its fine-scale morphology close to the jet base where highly variable-ray emission is thought to originate, according to various models. The source was observed during four days in April 2017 with the Event Horizon Telescope at 230 GHz, including the phased Atacama Large Millimeter/submillimeter Array, at an angular resolution of ∼20 μas (at a redshift of z = 0:536 this corresponds to ∼0:13 pc ∼ 1700 Schwarzschild radii with a black hole mass MBH = 8 × 108 M⊙). Imaging and model-fitting techniques were applied to the data to parameterize the fine-scale source structure and its variation.We find a multicomponent inner jet morphology with the northernmost component elongated perpendicular to the direction of the jet, as imaged at longer wavelengths. The elongated nuclear structure is consistent on all four observing days and across diffierent imaging methods and model-fitting techniques, and therefore appears robust. Owing to its compactness and brightness, we associate the northern nuclear structure as the VLBI "core". This morphology can be interpreted as either a broad resolved jet base or a spatially bent jet.We also find significant day-to-day variations in the closure phases, which appear most pronounced on the triangles with the longest baselines. Our analysis shows that this variation is related to a systematic change of the source structure. Two inner jet components move non-radially at apparent speeds of ∼15 c and ∼20 c (∼1:3 and ∼1:7 μas day-1, respectively), which more strongly supports the scenario of traveling shocks or instabilities in a bent, possibly rotating jet. The observed apparent speeds are also coincident with the 3C 279 large-scale jet kinematics observed at longer (cm) wavelengths, suggesting no significant jet acceleration between the 1.3mm core and the outer jet. The intrinsic brightness temperature of the jet components are ≤1010 K, a magnitude or more lower than typical values seen at ≥7mm wavelengths. The low brightness temperature and morphological complexity suggest that the core region of 3C 279 becomes optically thin at short (mm) wavelengths. © J.-Y. Kim et al. 2020.
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DOI：
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发表时间：
1984-03
期刊：
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影响因子：
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作者：
J. Culhane
通讯作者：
J. Culhane
DOI：
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发表时间：
1991
期刊：
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DOI：
10.1142/s2251158x13000362
发表时间：
2006
期刊：
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影响因子：
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DOI：
10.1017/s0021911800151836
发表时间：
1967-09
期刊：
The Journal of Asian Studies
影响因子：
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作者：
Jian Gao;Ruitao Jia;Qing Su
通讯作者：
Jian Gao;Ruitao Jia;Qing Su
DOI：
10.1007/978-1-349-94186-5_1200
发表时间：
2018-11
期刊：
The Grants Register 2022
影响因子：
--
作者：
Alexander Powell;AF Powell
通讯作者：
Alexander Powell;AF Powell