相互作用偶极场中的磁零点
Magnetic nulls in interacting dipolar fields
摘要：
在重联理论中，零的突出性是由于期望的奇异电流密度和磁场线在零处的不确定性。电子惯性改变了这两个特征的含义。只有当磁场线的最近距离超过距离$Δ_d$时，磁场线才是可区分的。电子惯性确保了$Δ_d\gtrsim c/ω_{pe}$。在磁场强度$B$最强的地方，位于半径为$Δ_d$的磁通量管内的线基本上是不可区分的。如果管沿其长度的某个地方包围了$B=0$消失的点，则可区分的线不会比$\approx (a^2c/ω_{pe})^{1/3}$更接近零，其中$a$是磁场的特征空间尺度。研究了空间恒定磁场中偶极子在零值存在时的磁场线行为。除了可扩展性的影响，在一个零电流密度的约束，并推导出薄电流片出现所需的时间。
英文摘要：
The prominence of nulls in reconnection theory is due to the expected singular current density and the indeterminacy of field-lines at a magnetic null. Electron inertia changes the implications of both features. Magnetic field lines are distinguishable only when their distance of closest approach exceeds a distance $Δ_d$. Electron inertia ensures $Δ_d\gtrsim c/ω_{pe}$. The lines that lie within a magnetic flux tube of radius $Δ_d$ at the place where the field strength $B$ is strongest are fundamentally indistinguishable. If the tube, somewhere along its length, encloses a point where $B=0$,vanishes, then distinguishable lines come no closer to the null than $\approx (a^2c/ω_{pe})^{1/3}$, where $a$ is a characteristic spatial scale of the magnetic field. The behavior of the magnetic field lines in the presence of nulls is studied for a dipole embedded in a spatially constant magnetic field. In addition to the implications of distinguishability, a constraint on the current density at a null is obtained, and the time required for thin current sheets to arise is derived.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
