论文标题
用星际闪烁测试太阳风的Alfvén-Wave模型
Testing the Alfvén-wave model of the solar wind with interplanetary scintillation
论文作者
论文摘要
了解太阳风加速度的机制在天体物理学和地球物理中很重要。太阳能加速度的有前途的模型被称为波/湍流驱动(WTD)模型,其中Alfvén波将能量馈入太阳风。在这项研究中,我们通过全球测量星际闪烁(IPS)观察的风速测量了WTD模型。对于最小和最大活性阶段中的Carrington旋转,我们选择了高纬度和中纬度的势场源表面方法计算出的田间线,并比较了模拟和观察到的风速。通过求解从光球到太阳风的磁水动力学方程来以自洽的方式进行仿真。在高纬度区域,模拟的太阳风速与IPS观察更好的一致性比与经典的王 - 王 - - sheeley的经验估计在最大和最小活性阶段相比。在中纬度地区,该协议恶化,可能是由于WTD模型和/或磁场外推的不准确性。我们的结果表明,高纬度太阳风可能是由波和湍流驱动的,并且基于物理学的太阳风速预测是高度可行性的,可以改善磁场外推。
Understanding the mechanism(s) of the solar wind acceleration is important in astrophysics and geophysics. A promising model of the solar wind acceleration is known as the wave/turbulence-driven (WTD) model, in which Alfvén waves feed energy to the solar wind. In this study, we tested the WTD model with global measurement of wind speed from interplanetary scintillation (IPS) observations. For Carrington rotations in minimal and maximal activity phases, we selected field lines calculated by the potential-field source-surface method in high- and mid-latitudes and compared the simulated and observed wind velocities. The simulation was performed in a self-consistent manner by solving the magnetohydrodynamic equations from the photosphere to the solar wind. In high-latitude regions, the simulated solar wind velocity agrees better with the IPS observation than with the classical Wang--Sheeley empirical estimation, both in maximal and minimal activity phases. In mid-latitude regions, the agreement worsens, possibly because of the inaccuracy of the WTD model and/or the magnetic-field extrapolation. Our results indicate that the high-latitude solar wind is likely to be driven by waves and turbulence, and that the physics-based prediction of the solar wind velocity is highly feasible with an improved magnetic-field extrapolation.