太阳宁静区磁场的功率谱分析

Power Spectrum Analysis of Magnetic Fields in a Solar Quiet Region

利用１９９８年１０月３日北京天文台怀柔太阳观测站的高质量磁图，对给定的太阳宁静区两种不同极性的磁场进行了功率谱分析．结果表明，空间功率谱在超米粒和中米粒尺度具有明显的尖峰结构，这对应于空间周期性分布的网络和内网络磁结构．结果也显示出，超米粒边缘所包含的两种极性场中，其中的一种极性占优势．通过瞬态功率谱的分析，得出网络和内网络场寿命之间的比例关系，这一结果和其他学者得出的超米粒和中米粒对流寿命之间的关系相符．

Using the high quality magnetograms acquired at Huairou Solar Observing Station of Beijing Astronomical Observatory on 1998 Oct. 3, we constructed the power spectrum for small-scale magnetic fields in a specified quiet region. The results show that there are obvious peaks in the spatial power spectrum at scales of supergranules and mesogranules. These peaks correspond to network and intranetwork magnetic fields with spatial periodic structure. The results also show that the negative polarity magnetic fields are dominant on the sides of supergranules. From the temporal power spectra we obtain the relationship between the lifetimes of network and intranetwork magnetic fields, which we find to be consistent with that between supergranules and mesogranules obtained by other authors.