伽马射线辐射的彗头射电星系在并合星系团Abell 3627的热介质中穿行

中文摘要 AI 辅助

彗头射电源是喷流活动星系核（AGN），它们在星系团致密的星系团内介质中运动。它们在伽马射线波段极为罕见，可能是因为它们通常以大视角被观测到。因此，每一次对彗头射电星系的新伽马射线探测都使我们能够探究这类独特AGN高能辐射的起源。在此，我们首次报道了位于并合星系团Abell 3627外围的彗头射电星系ESO~0137-G007（z=0.016）与伽马射线源FL16Y~J1615.5$-$6034的关联。该星系在致密星系团环境中的运动以及随后的冲压压力和/或星系团内介质湍流，导致形成了长度超过500千秒差距的喷流，其射电形态呈扭曲、蜿蜒状。利用4.1米SOAR望远镜获得的光学光谱缺乏发射线，表明其潜在的吸积活动在辐射上是低效的。根据测量的视线方向恒星速度弥散，我们估计中心超大质量黑洞的质量为$(3.36\pm1.32)\times10^9$太阳质量。我们简要讨论了若干辐射模型，以解释ESO~0137$-$G007观测到的宽带光谱能量分布。我们得出结论，对这一独特的伽马射线辐射彗头射电星系进行更深入的多波段观测，将使我们更好地理解喷流与热星系团环境的相互作用，从而为即将到来的平方千米阵对该类AGN的研究奠定基础。

英文摘要

Head-tail radio sources are jetted active galactic nuclei (AGN) moving through the dense intracluster medium of galaxy clusters. They are extremely rare in the gamma-ray sky, likely because they are usually observed at large viewing angles. Therefore, every new gamma-ray detection of head-tail radio galaxies allows us to probe the origin of the high-energy emission in this unique class of AGN. Here we report, for the first time, the association of ESO~0137-G007 (z=0.016), a head-tail radio galaxy located at the outskirts of the merging cluster Abell 3627, with the gamma-ray source FL16Y~J1615.5$-$6034. The motion of the galaxy through the dense cluster environment and subsequent ram pressure and/or intracluster medium turbulence have led to the formation of a $>$500 kpc-long jet exhibiting a twisted, wiggly radio morphology. Its optical spectrum, obtained with the 4.1 m SOAR telescope, is devoid of emission lines, indicating that the underlying accretion activity is radiatively inefficient. From the measured line-of-sight stellar velocity dispersion, we estimate the mass of the central supermassive black hole to be $(3.36\pm1.32)\times10^9$ \Msun. We briefly discuss several radiative models to explain the observed broadband spectral energy distribution of ESO~0137$-$G007. We conclude that deeper multi-wavelength observations of this unique gamma-ray emitting head-tail radio galaxy will enable us to better understand the interaction of the jet with the hot cluster environment, thus setting the stage for the research of this class of AGN with the upcoming Square Kilometer Array.

发表机构

• Inter-University Centre for Astronomy and Astrophysics (IUCAA)（天文与天体物理大学间中心）
• Centre for Space Research, North-West University（西北大学太空研究中心）
• International Gemini Observatory/NSF NOIRLab（国际双星观测台/美国国家光学红外天文实验室）
• Indian Institute of Astrophysics（印度天体物理研究所）
• Universität Bielefeld（比勒费尔德大学）
• Assam Don Bosco University（阿萨姆唐博斯科大学）
• Dayanand Science College（戴亚南德科学学院）

机构由 AI 辅助整理，请以论文原文为准。

补充信息

备注

ApJ, in press