论文标题
环核致密的气盘加油附近的宽银河NGC 4261中的活性银河核
Circumnuclear dense gas disk fuelling the active galactic nucleus in the nearby radio galaxy NGC 4261
论文作者
论文摘要
射电星系的过环磁盘（CND）中的冷分子气提供了关键信息，以理解质量积聚到活性银河核上。我们使用北部扩展的毫米阵列介绍了来自附近宽银河系的环形区域的第一个检测和图的HCN J = 1-0和HCO+ J = 1-0发射线。相对于星系的全身速度，在 +-700 km/s的径向速度下检测到两种分子线，它们是由CND产生的，外半径为100 pc。 HCN和HCO+的速度场拟合了开普勒磁盘旋转。封闭的质量为（1.6+-0.1）x10^9 m_solar，假设磁盘倾斜角为64度。 80 GHz处的连续图揭示了沿东西方向延伸超过5 kpc的弱的双面射流结构，中心的明亮核心。 80和230 GHz之间的连续频谱显示-0.34+-0.02的光谱指数，这表明光学薄的同步子辐射。与CND相关的致密气体质量为6.03x10^7 m_solar。它支持CND中的致密气体与超级质量黑洞的积聚率之间的正相关性，尽管相关的参数存在不确定性。
The cold molecular gas in the circumnuclear disk (CND) of radio galaxies provides critical information for understanding the mass accretion onto active galactic nuclei. We present the first detection and maps of HCN J=1-0 and HCO+ J=1-0 emission lines from the circumnuclear region of a nearby radio galaxy, NGC 4261, using the Northern Extended Millimeter Array. Both molecular lines are detected at a radial velocity of +-700 km/s relative to the systemic velocity of the galaxy, and they arise from a CND with an outer radius of 100 pc. The velocity fields of HCN and HCO+ are fitted with a Keplerian disk rotation. The enclosed mass is (1.6+-0.1)x10^9 M_solar, assuming a disk inclination angle of 64 degree. The continuum image at 80 GHz reveals a weak two-sided jet structure extending over 5 kpc along the east-west direction and a bright core at the centre. The continuum spectrum between 80 and 230 GHz shows a spectral index of -0.34+-0.02, which suggests optically thin synchrotron radiation. The dense gas mass associated with the CND is calculated to be 6.03x10^7 M_solar. It supports a positive correlation between the dense gas mass in the CND and the accretion rate onto the supermassive black hole, though there are uncertainties in the parameters of the correlation.
