标题： 类星体人马座A东射电瓣的X射线发射探测 显示英文标题

标题： Detection of X-ray Emission from the Eastern Radio Lobe of PICTOR A

摘要： XMM-Newton卫星揭示了 Fanaroff-Riley II 射电星系绘架座A射电喷流东部的扩展X射线发射。 累积在一个覆盖大约整个射电喷流一半区域上的X射线光谱，可以用热模型和幂律很好地描述。 X射线发射可能是热的，并由绕星系气体受到扩展射电喷流冲击而产生，或者相反，由射电喷流中的相对论电子对宇宙微波背景光子的逆康普顿（IC）散射产生。 后一种可能性似乎得到了射电平均同步辐射指数与X射线能量斜率之间良好一致性的支持。 然而，如果是这种情况，从IC X射线和射电流量比较得出的磁场比在同一X射线区域内估计的等离子体能量平衡值低两倍以上。 显示英文摘要

摘要： The XMM-Newton satellite has revealed extended X-ray emission from the eastern radio lobe of the Fanaroff-Riley II Radio Galaxy Pictor A. The X-ray spectrum, accumulated on a region covering about half the entire radio lobe, is well described by both a thermal model and a power law. The X-ray emission could be thermal and produced by circum-galactic gas shocked by the expanding radio lobe or, alternatively, by Inverse Compton (IC) of cosmic microwave background photons by relativistic electrons in the lobe. The latter possibility seems to be supported by the good agreement between the lobe-average synchrotron radio index and the X-ray energy slope. However, if this is the case, the magnetic field, as deduced from the comparison of the IC X-ray and radio fluxes, is more than a factor 2 below the equipartition value estimated in the same X-ray region.