论文标题
在相对论磁化喷气机边界处的开尔文 - 螺旋杆菌不稳定性
The Kelvin-Helmholtz instability at the boundary of relativistic magnetized jets
论文作者
论文摘要
我们研究了平面界面的线性稳定性，该平面界面将两个流体分开相对运动，重点是适合相对论喷射的边界的条件。射流是磁性的，而环境风是气压主导的。我们得出了分散关系的最通用形式，并为其解决方案提供了与JetAlfvén速度$ V_A $小得多的环境音速的分析近似，适用于现实的系统。稳定性特性主要取决于波形和射流磁场之间的角度$ψ$。对于$ψ=π/2 $，磁张力不起作用，我们的解决方案类似于气压主导的射流之一。在这里，只有子alfvénic喷气机不稳定（$ 0 <m_e \ equiv（v/v_a）\cosθ<1 $，其中$ v $是剪切速度，$θ$是速度和波形之间的角度）。对于$ψ= 0 $，速度剪切中的自由能需要克服磁性张力，并且只有超级alfvénic喷气机不稳定（$ 1 <m_e <\ sqrt {（（1+γ_w^^2）/[1+（v_a/c）我们的结果对相对论磁化喷气机的繁殖和发射具有重要意义。
We study the linear stability of a planar interface separating two fluids in relative motion, focusing on conditions appropriate for the boundaries of relativistic jets. The jet is magnetically dominated, whereas the ambient wind is gas-pressure dominated. We derive the most general form of the dispersion relation and provide an analytical approximation of its solution for an ambient sound speed much smaller than the jet Alfvén speed $v_A$, as appropriate for realistic systems. The stability properties are chiefly determined by the angle $ψ$ between the wavevector and the jet magnetic field. For $ψ=π/2$, magnetic tension plays no role, and our solution resembles the one of a gas-pressure dominated jet. Here, only sub-Alfvénic jets are unstable ($0<M_e\equiv(v/v_A)\cosθ<1$, where $v$ is the shear velocity and $θ$ the angle between the velocity and the wavevector). For $ψ=0$, the free energy in the velocity shear needs to overcome the magnetic tension, and only super-Alfvénic jets are unstable ($1<M_e<\sqrt{(1+Γ_w^2)/[1+(v_A/c)^2Γ_w^2]}$, with $Γ_w$ the wind adiabatic index). Our results have important implications for the propagation and emission of relativistic magnetized jets.
