X形射电星系PKS 2014-55中的流体动力学回流
Hydrodynamical Backflow in X-shaped Radio Galaxy PKS 2014-55
摘要：
我们呈现了MeerKAT 1.28 GHz的总强度，偏振和光谱指数图像，覆盖了巨大的（投影长度$l \approx 1.57$ ~Mpc）X形射电源PKS~2014 $-$ 55，具有前所未有的亮度灵敏度和角分辨率的组合。它们显示了由宿主星系PGC~064440的大而倾斜的热气晕偏转的直主喷流的流体动力学回流的清晰的“双回旋镖”形态。PKS~2014 $-$ 55中的磁场方向遵循从射流穿过副翼的流线。射电源嵌入在微弱的（$T_\mathrm{b} \approx 0.5 \mathrm{\,K}$）茧具有均匀的亮度温度和尖锐的外边缘特征的亚音速膨胀到周围的组内介质。小得多的（$l \sim 25$ ~kpc）重新启动的中心源的位置角在主喷流的$5^\circ$范围内，排除了引起喷流重新定向或两个独立喷流的模型。回流中的压缩和湍流可能产生每个回飞棒顶点后面的不规则的和低偏振的亮区以及具有亮头和暗尾的流动中的几个特征。
英文摘要：
We present MeerKAT 1.28 GHz total-intensity, polarization, and spectral-index images covering the giant (projected length $l \approx 1.57$~Mpc) X-shaped radio source PKS~2014$-$55 with an unprecedented combination of brightness sensitivity and angular resolution. They show the clear "double boomerang" morphology of hydrodynamical backflows from the straight main jets deflected by the large and oblique hot-gas halo of the host galaxy PGC~064440. The magnetic field orientation in PKS~2014$-$55 follows the flow lines from the jets through the secondary wings. The radio source is embedded in faint ($T_\mathrm{b} \approx 0.5 \mathrm{\,K}$) cocoons having the uniform brightness temperature and sharp outer edges characteristic of subsonic expansion into the ambient intra-group medium. The position angle of the much smaller ($l \sim 25$~kpc) restarted central source is within $5^\circ$ of the main jets, ruling out models that invoke jet re-orientation or two independent jets. Compression and turbulence in the backflows probably produce the irregular and low polarization bright region behind the apex of each boomerang as well as several features in the flow with bright heads and dark tails.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
