Title: Total and linearly polarized synchrotron emission from overpressured magnetized relativistic jets Show Chinese title

Title: 总和线性偏振的同步辐射来自过压磁化相对论喷流

Abstract: We present relativistic magnetohydrodynamic (RMHD) simulations of stationary overpressured magnetized relativistic jets which are characterized by their dominant type of energy, namely internal, kinetic, or magnetic. Each model is threaded by a helical magnetic field with a pitch angle of $45^\circ$ and features a series of recollimation shocks produced by the initial pressure mismatch, whose strength and number varies as a function of the dominant type of energy. We perform a study of the polarization signatures from these models by integrating the radiative transfer equations for synchrotron radiation using as inputs the RMHD solutions. These simulations show a top-down emission asymmetry produced by the helical magnetic field and a progressive confinement of the emission into a jet spine as the magnetization increases and the internal energy of the non-thermal population is considered to be a constant fraction of the thermal one. Bright stationary components associated with the recollimation shocks appear presenting a relative intensity modulated by the Doppler boosting ratio between the pre-shock and post-shock states. Small viewing angles show a roughly bimodal distribution in the polarization angle due to the helical structure of the magnetic field, which is also responsible for the highly stratified degree of linear polarization across the jet width. In addition, small variations of the order of $26^\circ$ are observed in the polarization angle of the stationary components, which can be used to identify recollimation shocks in astrophysical jets. Show Chinese abstract

Abstract: 我们展示了静态过压磁化相对论喷流的相对论磁流体动力学（RMHD）模拟，这些喷流以它们主要的能量类型为特征，即内部能、动能或磁能。 每个模型都由具有$45^\circ$俯角的螺旋磁场贯穿，并且由于初始压力不匹配而产生一系列再压缩激波，其强度和数量随主要能量类型的函数而变化。 我们通过使用RMHD解作为输入，对这些模型的偏振特征进行了研究，积分了同步辐射的辐射转移方程。 这些模拟显示了由螺旋磁场产生的自上而下的发射不对称性，并且随着磁化率的增加，非热种群的内能被考虑为热能的固定比例，发射逐渐集中在喷流核心。 与再压缩激波相关的明亮静态组分出现，其相对强度由激波前和激波后的多普勒增强比调制。 小视角显示出偏振角度的近似双峰分布，这是由于磁场的螺旋结构造成的，这也导致了喷流宽度上的高度分层的线性偏振度。 此外，在静态组分的偏振角度中观察到约$26^\circ$的小变化，这可以用来在天体物理喷流中识别再压缩激波。