论文标题
外层射流的不同口味：相对论流下降的作用
The different flavors of extragalactic jets: the role of relativistic flow deceleration
论文作者
论文摘要
我们对相对论（洛伦兹因子为10）进行三维数值模拟，在均匀密度环境中传播的非磁化喷气机，以研究夹带的效果和随之而来的减速。我们的模拟研究了星系芯内的喷射繁殖，最有可能在其中更有效地发生减速。我们比较具有不同密度和压力比的病例相对于环境介质的发现，即低密度喷气机被有效减速并达到准稳态，在这种稳定状态下，在600个射流半径上，从高度下降到亚相关性速度。在相反的情况下，较密集的喷气机在相同的长度上保持高度相对论的速度。我们讨论了这些结果与Faranoff Riley（FR）无线电源分类。我们推断，较低的密度喷气机可以产生FR 0和FR I无线电，而较高的密度喷气机可以连接到FR II无线电源。
We perform three-dimensional numerical simulations of relativistic (with a Lorentz factor of 10), non magnetized jets propagating in a uniform density environment, in order to study the effect of the entrainment and the consequent deceleration. Our simulations investigate the jet propagation inside the galaxy core, where, most likely, the deceleration occurs more efficiently. We compare cases with different density and pressure ratios with respect to the ambient medium finding that low density jets are efficiently decelerated and reach a quasi steady state in which, over a length of 600 jet radii, slow down from highly to sub-relativistic velocities. At the opposite, denser jets keep highly relativistic velocity over the same length. We discuss these results in relation to the Faranoff Riley (FR) radio-sources classification. We infer that lower density jets can give rise to FR 0 and FR I radio-sources, while higher density jets may be connected to FR II radio-sources.
