Large-scale horizontal flows in the solar photosphere - II. Long-term behaviour and magnetic activity response
Large-scale horizontal flows in the solar photosphere - II. Long-term behaviour and magnetic activity response
复制标题
太阳光球层中的大规模水平流动 - II。
DOI：
10.1051/0004-6361:20077718
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发表时间：
2007
影响因子：
6.5
通讯作者：
Czech Republic
中科院分区：
文献类型：
--
作者：
M. Švanda;M. Klvaňa;M. Sobotka;V. B. A. I. O. A. O. Sciences;v.v.i.;Ondrejov;Czech Republic Astronomical Institute of Charles University;Prague;Czech Republic
我们已经开发了一种方法来映射大规模的水平速度场在太阳光球。该方法的开发，调整，并使用合成数据校准。现在，我们将该方法应用于几乎覆盖一个太阳周期的迈克尔逊多普勒成像仪（MDI）Dopplergrams系列，以生成有关表面流的长期行为的信息。我们的方法清楚地再现了被广泛接受的平均流场分量的属性，如扭转振荡和对流环流的模式。我们还进行了周期分析，但由于数据序列长度和较大的差距，我们没有检测到任何显著的周期。研究了磁活动与平均纬向运动的关系。我们发现的证据表明，出现紧凑的磁性区域局部加速旋转的超颗粒图案在其附近，磁场的存在下，一般减速在赤道地区的旋转。我们的研究结果表明，在赤道地区的活动区出现，表现出恒定的速度（比卡林顿速率快60\pm 9$ m s-1），这表明他们出现在0.95\ R\odot$的表面径向剪切的基础上，断开其磁根，并在其演变过程中减慢。
We have developed a method to map large-scale horizontal velocity fields in the solar photosphere. The method was developed, tuned, and calibrated using synthetic data. Now, we apply the method to the series of Michelson Doppler Imager (MDI) Dopplergrams covering almost one solar cycle to generate the information about the long-term behaviour of surface flows. Our method clearly reproduces the widely accepted properties of mean flow field components, such as torsional oscillations and a pattern of meridional circulation. We also performed a period analysis, however due to the data series length and large gaps we did not detect any significant periods. The relation between the magnetic activity and the mean zonal motion is studied. We found evidence that the emergence of compact magnetic regions locally accelerates the rotation of the supergranular pattern in their vicinity and that the presence of magnetic fields generally decelerates the rotation in the equatorial region. Our results show that active regions in the equatorial region emerge, exhibiting a constant velocity (faster by $60 \pm 9$ m s -1 than the Carrington rate), suggesting that they emerge from the base of the surface radial shear at $0.95\ R_\odot$, disconnect from their magnetic roots, and slow down during their evolution.