标题： ALMA观测到的塞弗特星系IC5063中的快速分子外流 显示英文标题

标题： The fast molecular outflow in the Seyfert galaxy IC5063 as seen by ALMA

摘要： 我们利用 ALMA 进行的高分辨率（0.5弧秒）CO(2-1)观测来追踪 Seyfert 2 星系 IC5063 中分子气体的动力学。 一股快速向外流动的分子气体沿着整个射电喷流延伸，在射电源西区较亮的热点附近约 0.5 千秒差距处达到最高的流出速度。 数据显示存在一股质量巨大、速度高达 650 公里/秒的冷分子气体快速外流，此外还有一股此前在温暖 H2、HI 和电离气体中检测到的外流。 中心活动星系核（AGN）和射电喷流都可能在能量上驱动这种外流。 然而，外流气体的特征表明射电喷流是主要驱动力。 这很重要，因为尽管 IC5063 是最强大的 Seyfert 星系之一，但它是一个相对较弱的射电源（P = 3×10^23 W/Hz）。 所有观测到的特征都可以用一种射电等离子体喷流扩展到块状介质中的情景来描述，直接与云相互作用并膨胀出一个推动星际介质横向外流的茧状结构。 该模型与最近模拟的结果一致，例如 Wagner 等人的研究结果。在较亮的西区位置存在喷流与气体云之间更强、更直接的相互作用。 即使假设 CO 转化为 H2 的因子取最保守值，外流气体的质量范围在 1.9 到 4.8×10^7 太阳质量之间。 这些数量远远大于温暖气体（分子和电离）的外流量，并且略大于 HI 外流量。 这表明大部分观测到的冷分子外流是由于受到冲击后快速冷却所致。 这种气体是冷却过程的最终产物。 我们的 CO 观测表明，相对论性喷流可以驱动分子气体的快速外流。 显示英文摘要

摘要： We use high-resolution (0.5 arcsec) CO(2-1) observations performed with ALMA to trace the kinematics of the molecular gas in the Seyfert 2 galaxy IC5063. A fast outflow of molecular gas extends along the entire radio jet, with the highest outflow velocities about 0.5kpc from the nucleus, at the location of the brighter hot-spot in the W lobe. The data show that a massive, fast outflow with velocities up to 650 km/s of cold molecular gas is present, in addition to one detected earlier in warm H2, HI and ionised gas. Both the central AGN and the radio jet could energetically drive the outflow. However, the characteristics of the outflowing gas point to the radio jet being the main driver. This is important, because IC5063, although one of the most powerful Seyfert galaxies, is a relatively weak radio source (P = 3x10^23 W/Hz). All the observed characteristics can be described by a scenario of a radio plasma jet expanding into a clumpy medium, interacting directly with the clouds and inflating a cocoon that drives a lateral outflow into the interstellar medium. This model is consistent with results obtained by recent simulations such as those of Wagner et al.. A stronger, direct interaction between the jet and a gas cloud is present at the location of the brighter W lobe. Even assuming the most conservative values for the conversion factor CO-to-H2, the mass of the outflowing gas is between 1.9 and 4.8x10^7 Msun. These amounts are much larger than those of the outflow of warm gas (molecular and ionized) and somewhat larger than of the HI outflow. This suggests that most of the observed cold molecular outflow is due to fast cooling after being shocked. This gas is the end product of the cooling process. Our CO observations demonstrate that fast outflows of molecular gas can be driven by relativistic jets.