吸积白矮星上的磁约束山脉
Magnetically Confined Mountains on Accreting White Dwarfs
- Escola de Artes, Ciências e Humanidades, Universidade de São Paulo（圣保罗大学艺术、科学与人文学院）
- Instituto de Física de São Carlos, Universidade de São Paulo（圣保罗大学圣卡洛斯物理研究所）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
本文通过数值求解Grad-Shafranov方程，研究了吸积白矮星上磁约束山脉的结构及其对磁场的影响，发现山脉可使磁场线变形并拖向赤道，吸积可掩埋磁场至原值的10%，并给出了最大可约束质量的数学关系。
中文摘要 AI 辅助
本文计算了吸积白矮星上磁约束山脉的磁流体结构，以及吸积对恒星磁场减弱的影响。通过采用强制执行磁通冻结的自洽方案数值求解Grad-Shafranov方程，获得了山脉的平衡结构。对于特征系统参数，研究表明，质量约为$10^{-3}M_\bullet$、特征高度约为$10^5\\,\mathrm{cm}$的山脉会显著使磁场线变形并将其拖向赤道。本文得到了白矮星在给定恒星磁场和温度下能够磁约束的最大质量的数学关系式。研究发现，吸积通过将恒星磁场降低至其吸积前值的$10\\%$来掩埋恒星磁场。恒星磁场仍以偶极为主，但附加了多极分量。
英文摘要
The hydromagnetic structure of magnetically confined mountains on accreting white dwarfs is computed, alongside the effects of accretion on the reduction of the star's magnetic field. The equilibrium structure of the mountain is obtained by numerically solving the Grad-Shafranov equation with a self-consistent scheme that enforces magnetic flux freezing. For characteristic system parameters, it is shown that magnetic field lines are significantly deformed and dragged equatorwards by mountains with masses $\sim10^{-3}M_\odot$ that have a characteristic height of $\sim10^5\,\mathrm{cm}$. A mathematical relation is obtained for the maximum mass that a white dwarf can confine magnetically given the star's magnetic field and temperature. It is found that the accretion buries the star's magnetic field by reducing it by up to $10\%$ of its pre-accretion value. The star's magnetic field remains dominantly dipolar, but with added multipolar components.
