论文标题
完全对流M矮人的模拟：具有不同磁性prandtl数字的发电机作用
Simulations of fully convective M dwarfs: dynamo action with varying magnetic Prandtl numbers
论文作者
论文摘要
M矮人是低质量主序列恒星，这是太阳邻域中最多的恒星，已知具有显着的磁性活性。这项工作的目的是探索具有变化的磁性prandtl数字$ {\ rm pr_m} $和旋转期（$ {\ rm p_ {rot}} $）为43天的发电机解决方案和磁场。已知$ {\ rm pr_m} $在发电机动作中起重要作用；低 - $ \ rm pr_m $和大 - $ \ rm pr_m $具有非常不同的属性。我们使用``star-in-a-a-box'''模型进行了三维磁流失动力学（MHD）数值仿真，该模型使用M5矮人的恒星参数，售价为0.21 m _ {\ odot} $。我们发现，发电机解决方案对$ {\ rm pr_m} $敏感。在此旋转期间的模拟当前的大规模磁场的周期性周期最高为$ {\ rm pr_m} \ leq 2 $;对于较高的值，循环消失了，不规则的解决方案出现。我们的结果与以前的研究一致，并表明在完全对流恒星中工作的发电机与部分对流恒星的行为相似。
M dwarfs are low-mass main-sequence stars, the most numerous type of stars in the solar neighbourhood, which are known to have significant magnetic activity. The aim of this work is to explore the dynamo solutions and magnetic fields of fully convective M dwarfs with varying magnetic Prandtl numbers ${\rm Pr_M}$, and a rotation period (${\rm P_{rot}}$) of 43 days. ${\rm Pr_M}$ is known to play an important role in the dynamo action; dynamos for low-$\rm Pr_M$ and large-$\rm Pr_M$ have very different properties. We performed three-dimensional magnetohydrodynamical (MHD) numerical simulations with the ``star-in-a-box'' model using stellar parameters for an M5 dwarf with $0.21 M_{\odot}$. We found that the dynamo solutions are sensitive to ${\rm Pr_M}$. The simulations at this rotation period present periodic cycles of the large-scale magnetic field up to ${\rm Pr_M} \leq 2$; for higher values the cycles disappear and irregular solutions to arise. Our results are consistent with previous studies and suggest that the dynamos operating in fully convective stars behave similarly as those in partially convective stars.
