由观测和数值模拟得到的小磁通量单元对f模的散射
Scattering of the f-mode by small magnetic flux elements from observations and numerical simulations
摘要：
利用三维数值模拟方法分析了磁管对f模的散射。一个f模波包在太阳大气中传播，大气中埋有三种不同的通量管模型，它们的半径和总磁通量不同。还执行了不存在管的安静Sun模拟作为参考。在磁通管中激发波，沿磁力线传播，在磁通管周围产生夹套模，夹套模携带的能量是磁通管模的40%。所得到的散射波主要是由m=0和m=+/-1模式的混合组成的f模式。散射波的振幅与磁通量近似成比例。少量的功率被散射到p_1模中。我们已经评估了吸收和相移的光球垂直速度的傅立叶-汉克尔分解。它们进行了比较，从emperature平均的高分辨率MDI多普勒数据管中观察到的3400个小磁性元素的结果。比较表明，观测到的相移与波数的依赖关系可以匹配合理，以及与模拟通量管模型。观察到的变化的相移与方位角的顺序$m$出现依赖于集合平均的细节，包括可能的运动的磁性元件和不对称形状的元素。
英文摘要：
The scattering of f-modes by magnetic tubes is analyzed using three-dimensional numerical simulations. An f-mode wave packet is propagated through a solar atmosphere embedded with three different flux tube models which differ in radius and total magnetic flux. A quiet Sun simulation without a tube present is also performed as a reference. Waves are excited inside the flux tube and propagate along the field lines, and jacket modes are generated in the surroundings of the flux tube, carrying 40% as much energy as the tube modes. The resulting scattered wave is mainly an f-mode composed of a mixture of m=0 and m=+/-1 modes. The amplitude of the scattered wave approximately scales with the magnetic flux. A small amount of power is scattered into the p_1-mode. We have evaluated the absorption and phase shift from a Fourier-Hankel decomposition of the photospheric vertical velocities. They are compared with the results obtained from the emsemble average of 3400 small magnetic elements observed in high-resolution MDI Doppler datacubes. The comparison shows that the observed dependence of the phase shift with wavenumber can be matched reasonably well with the simulated flux tube model. The observed variation of the phase-shifts with the azimuthal order $m$ appears to depend on details of the ensemble averaging, including possible motions of the magnetic elements and asymmetrically shaped elements.
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。
