论文标题
根据SDO/HMI和Goode太阳能望远镜数据分析安静的湍流
Analysis of quiet-sun turbulence on the basis of SDO/HMI and Goode Solar Telescope data
论文作者
论文摘要
我们使用Helioseissic和磁成像仪（HMI）在板载太阳能动态观测站（SDO）和近红外成像光谱仪（NIRIS）在Goode Solar Telescope（GST）上运行的近红外成像光谱仪（NIRIS）在板载板上，分析了不受干扰的光电球的视线线和磁力谱。在NIRIS数据中，数据显示直径为200-400〜km的薄通量管，田间强度为1000-2000〜g。确定为冠状孔，安静的太阳和块状区域确定的HMI功率光谱在广泛的空间尺度上显示出相同的光谱指数为-1，从10-20〜mm降至2.4〜mm。这意味着在不受干扰的光球中，磁场产生的相同机制在任何地方运行。最合理的是局部湍流元分。与HMI光谱相比，NIRIS光谱的-1.2斜率似乎更延伸到短空间范围内，直到在0.8-0.9〜mm处截止，之后它继续以-2.2的陡峭斜率为-2.2。观察到的和kolmogorov型光谱的比较使我们能够推断出kolmogorov湍流级联反应不能占3.5-0.3毫米比例范围内观察到的总磁能的35 \％。能量过量可以归因于田间产生的其他机制，例如在不受干扰的光电球中观察到的局部湍流发电机和磁性超扩张性，该光球可以减慢kolmogorov级联反应的速度，从而导致较浅的频谱。
We analysed line-of-sight magnetic fields and magnetic power spectra of an undisturbed photosphere using magnetograms acquired by the Helioseismic and Magnetic Imager (HMI) on-board the Solar Dynamic Observatory (SDO) and the Near InfraRed Imaging Spectrapolarimeter (NIRIS) operating at the Goode Solar Telescope (GST) of the Big Bear Solar Observatory. In the NIRIS data revealed the presence of thin flux tubes of 200-400~km in diameter and of field strength of 1000-2000~G. The HMI power spectra determined for a coronal hole, a quiet sun and a plage areas exhibit the same spectral index of -1 on a broad range of spatial scales from 10-20~Mm down to 2.4~Mm. This implies that the same mechanism(s) of magnetic field generation operate everywhere in the undisturbed photosphere. The most plausible one is the local turbulent dynamo. When compared to the HMI spectra, the -1.2 slope of the NIRIS spectrum appears to be more extended into the short spatial range until the cutoff at 0.8-0.9~Mm, after which it continues with a steeper slope of -2.2. Comparison of the observed and Kolmogorov-type spectra allowed us to infer that the Kolmogorov turbulent cascade cannot account for more than 35\% of the total magnetic energy observed in the scale range of 3.5-0.3~Mm. The energy excess can be attributed to other mechanisms of field generation such as the local turbulent dynamo and magnetic super-diffusivity observed in an undisturbed photosphere that can slow down the rate of the Kolmogorov cascade leading to a shallower resulting spectrum.
