论文标题
一座巨大的无线电桥，连接了阿贝尔1758的两个群集
A giant radio bridge connecting two clusters in Abell 1758
论文作者
论文摘要
星系簇之间的碰撞通过湍流和冲击散发出大量的能量（ICM）。在此过程中，可以形成无线电晕和文物形式的MPC尺度扩散同步加速器发射。但是，关于碰撞的早期阶段知之甚少。我们使用了从53 MHz到1.5 GHz的深度无线电观察结果，研究了预合并的Galaxy群集A1758N和A1758，分别为$ \ sim2 $ MPC。我们确认存在连接两个系统的巨大无线电发射桥，这仅在我们较早的工作中暂时报告。这是迄今为止在群集对中观察到的第二个大型无线电桥。该桥在144 MHz的Lofar图像中可见，并在53 MHz处进行暂定检测。它的平均无线电发射率比A1758N和A1758中的无线电光环低一个数量级。有趣的是，桥的无线电和X射线排放是相关的。我们的结果表明，ICM中的非热现象也可以在插入系统之间的压缩气体区域产生。
Collisions between galaxy clusters dissipate enormous amounts of energy in the intra-cluster medium (ICM) through turbulence and shocks. In the process, Mpc-scale diffuse synchrotron emission in form of radio halos and relics can form. However, little is known about the very early phase of the collision. We used deep radio observations from 53 MHz to 1.5 GHz to study the pre-merging galaxy clusters A1758N and A1758S that are $\sim2$ Mpc apart. We confirm the presence of a giant bridge of radio emission connecting the two systems that was reported only tentatively in our earlier work. This is the second large-scale radio bridge observed to date in a cluster pair. The bridge is clearly visible in the LOFAR image at 144 MHz and tentatively detected at 53 MHz. Its mean radio emissivity is more than one order of magnitude lower than that of the radio halos in A1758N and A1758S. Interestingly, the radio and X-ray emissions of the bridge are correlated. Our results indicate that non-thermal phenomena in the ICM can be generated also in the region of compressed gas in-between infalling systems.
