论文标题
磁性主导的天体物理喷气机和风的分析解决方案：喷气发射，加速和准确性
Analytical Solution of Magnetically Dominated Astrophysical Jets and Winds: Jet Launching, Acceleration, and Collimation
论文作者
论文摘要
我们提出了高度磁化喷射/风流的分析解决方案。一般无力的射流/风程方程（“ Pulsar”方程）的左侧分为旋转和非旋转项。具有两个项的两个方程式可以分析求解，并且两个解决方案相互匹配。因此，我们获得了磁性统治的射流/风的一般近似解，该解覆盖了从非依赖主义到相对论方案，漂移速度与冷等离子体速度匹配。喷气机的加速度包括三个阶段。 （1）射流流位于Alfvén临界表面（即光缸）内，具有非偏移速度，并且由环形运动主导。 （2）射流超出了Alfvén的临界表面，在该临界表面上，该流动由多型运动主导并成为相对论。这两个阶段的总速度遵循相同的法律$vγ=ωr$。 （3）进化定律被$vγ\ oit1/\ left（θ\ sqrt {2-ν} \ right）$取代，其中$θ$是喷气机的半开角，$ 0 \ 0 \leqν\ leq 2 $是由磁场配置确定的免费参数。这是因为较早的有效加速最终打破了喷气机中不同部分之间的因果关系，从而阻止了全局解决方案。该喷气机必须携带局部电荷和电流以支持电磁平衡。该近似解决方案与已知的理论结果和数值模拟一致，直接与观测值进行比较更为方便。该理论可用于约束天体物理喷气机中黑洞的自旋。
We present an analytical solution of a highly magnetized jet/wind flow. The left side of the general force-free jet/wind equation (the "pulsar" equation) is separated into a rotating and a nonrotating term. The two equations with either term can be solved analytically, and the two solutions match each other very well. Therefore, we obtain a general approximate solution of a magnetically dominated jet/wind, which covers from the nonrelativistic to relativistic regimes, with the drift velocity well matching the cold plasma velocity. The acceleration of a jet includes three stages. (1) The jet flow is located within the Alfvén critical surface (i.e. the light cylinder), has a nonrelativistic speed, and is dominated by toroidal motion. (2) The jet is beyond the Alfvén critical surface where the flow is dominated by poloidal motion and becomes relativistic. The total velocity in these two stages follows the same law $vΓ=ΩR$. (3) The evolution law is replaced by $vΓ\approx1/\left(θ\sqrt{2-ν}\right)$, where $θ$ is the half-opening angle of the jet and $0\leqν\leq2$ is a free parameter determined by the magnetic field configuration. This is because the earlier efficient acceleration finally breaks the causality connection between different parts in the jet, preventing a global solution. The jet has to carry local charges and currents to support an electromagnetic balance. This approximate solution is consistent with known theoretical results and numerical simulations, and it is more convenient to directly compare with observations. This theory may be used to constrain the spin of black holes in astrophysical jets.
