The X-ray Ribs Within the Cocoon Shock of Cygnus A
R. T. Duffy, D. M. Worrall, M. Birkinshaw, P. E. J. Nulsen, M. W. Wise, M. N. de Vries, B. Snios, W. G. Mathews, R. A. Perley, M. J. Hardcastle, D. A. Rafferty,… 展开作者
R. T. Duffy, D. M. Worrall, M. Birkinshaw, P. E. J. Nulsen, M. W. Wise, M. N. de Vries, B. Snios, W. G. Mathews, R. A. Perley, M. J. Hardcastle, D. A. Rafferty, B. R. McNamara, A. C. Edge, J. P. McKean, C. L. Carilli, J. H. Croston, L. E. H. Godfrey, R. A. Laing
We use new and archival Chandra observations of Cygnus A, totalling $\sim$1.9 Ms, to investigate the distribution and temperature structure of gas lying within the projected extent of the cocoon shock and exhibiting a rib-like structure. We confirm that the X-rays are dominated by thermal emission with an average temperature of around 4 keV, and have discovered an asymmetry in the temperature gradient, with the southwestern part of the gas cooler than the rest by up to 2 keV. Pressure estimates suggest that the gas is a coherent structure of single origin located inside the cocoon, with a mass of roughly $2\times10^{10} M_{\odot}$. We conclude that the gas is debris resulting from disintegration of the cool core of the Cygnus A cluster after the passage of the jet during the early stages of the current epoch of activity. The 4 keV gas now lies on the central inside surface of the hotter cocoon rim. The temperature gradient could result from an offset between the centre of the cluster core and the Cygnus A host galaxy at the switch-on of current radio activity.
Correlated GeV-TeV Gamma-Ray Emission from Extended Sources in the Cygnus Region
我们银河系的天鹅座臂是一个源丰富和复杂的区域，拥有多种伽马射线源类型，如脉冲星风星云（PWN），超新星遗迹，双星系统和星团。高海拔水切伦科夫（HAWC）天文台自2015年以来一直在收集数据，并报告了天鹅座地区的五个来源。其他一些仪器也观测到该区域的伽马射线源。例如，费米-LAT发现了GeV能量的伽马射线发射，这是由于一个新加速的宇宙射线茧，它与几个TeV伽马射线观测站看到的已知PWN TeV 2032+4130位于同一位置。TeV J2032+4130很可能是由脉冲星PSR J2032+4127提供动力，基于VERITAS报告的多波长观测和不对称形态。HAWC数据的研究将提供更多的信息，关于形态，发射起源，以及与GeV的发射的相关性。本报告将讨论对HAWC仪器和费米-LAT收集的数据的分析，以及所获得的结果，以提供对天鹅座茧在五十年的能量范围内的更深入的了解。
Spectrally Resolved Gas Kinematics in Cygnus A: XRISM Detects AGN Jet-induced Velocity Dispersion in Multi-temperature Gas
Space Research Organisation Netherlands（荷兰空间研究组织）；Center for Astrophysical Sciences, William H. Miller III Department of Physics and Astronomy, Johns Hopkins University（约翰斯·霍普金斯大学，威廉·H·米勒三世物理学与天文学系，天体物理学科学中心）；School of Earth and Space Exploration, Arizona State University（亚利桑那州立大学，地球与太空探索学院）；Leiden Observatory, Leiden University（莱顿大学，莱顿天文台）；Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo（东京大学，宇宙物理与数学卡弗里研究所）；RIKEN High Energy Astrophysics Laboratory（理化学研究所，高能天体物理实验室）；Department of Physics, Tokyo University of Science（东京理科大学，物理学系）；NASA / Goddard Space Flight Center（美国国家航空航天局，戈达德太空飞行中心）；Anton Pannekoek Institute, University of Amsterdam（阿姆斯特丹大学，安东·潘内科克研究所）
