Efficacy of magnetically driven temperature-dependent plastic flows in exciting the magnetosphere of CXOU J164710.2-455216
Efficacy of magnetically driven temperature-dependent plastic flows in exciting the magnetosphere of CXOU J164710.2-455216
复制标题
磁驱动的温度相关塑性流动在激励 CXOU 磁层中的功效 J164710.2-455216
DOI：
--
复制
发表时间：
2018
影响因子：
1.9
通讯作者：
Chu W. Kwang
中科院分区：
文献类型：
--
作者：
Chu W. Kwang
利用经过验证的过渡态理论和量子塑性理论，计算了中子星星（如CX164710.2 -455216）壳中磁驱动塑性流动的温度相关剪切（应变）速率和温度相关剪切（粘度）。在前人工作的基础上，如临界剪切应力和地壳的最小剪切（应变）率（约1 rad/year 1 ~mbox{rad}/mbox{year}$），我们的数值计算结果表明，中子星星地壳的塑性变形可以在外部磁场中引起很小的扭曲（或剪切）。然后，我们扩展兰德的计算磁层扭曲滑流的情况下，将产生电流的磁星的磁层，说，在Westerlund 1的CXEJ164710.2 -455216。后者被认为是Muno等人观察到的X射线爆发的直接原因，一旦我们考虑到CXOUJ 164710.2 -455216的年龄或历史，可以从现有的测量或观测中估计出相应磁场的相关能量标度。我们的研究结果和相关的能量尺度的分析证实了软伽玛中继爆发的开始是由地壳塑性运动引起的磁层耗散控制的。
Using verified transition state theory and quantum plasticity theory we calculate the temperature-dependent shear (strain) rates as well as temperature-dependent (shear) viscosity considering magnetically driven plastic flows in the neutron star (like CXOU J164710.2-455216) crust. Our numerical results which are based on previous works like the critical shear stress as well as the minimum shear (strain) rate of crust (around 1rad/year$1~mbox{rad}/mbox{year}$) demonstrate that a plastic deformation of the neutron star crust could induced a very slight twist (or shear) in the external magnetic field. We then extend Lander’s calculation of magnetospheric twist to slip-flow cases that will generated currents in the magnetosphere of the magnetar, say, CXOU J164710.2-455216 in Westerlund 1. The latter is believed to be the direct cause of the observed X-ray outburst by Muno et al. once we examine the associated energy scales for corresponding magnetic fields considering the age or history of CXOUJ164710.2-455216 which can be estimated from available measurements or observations. Our results and analysis of relevant energy scales confirm the onset of the soft gamma repeater outburst is controlled by magnetospheric dissipation induced by the plastic motions of the crust.