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arXiv 1205.2154astro-ph.SR
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用Hinode进行极场反射观测

Polar Field Reversal Observations with Hinode

D. Shiota, S. Tsuneta, M. Shimojo, N. Sako, D. Orozco Suárez, R. Ishikawa

摘要:

我们一直在用{ \it Hinode}上的太阳光学望远镜监测太阳极地磁场的年度变化,以记录它们的演变和在太阳极大期附近的预期逆转。自动识别磁通量图中的所有磁性片,以获得作为每个片的总磁通量的函数的数量密度和磁通量密度。每个贴片检测到的磁通量的范围超过四个数量级($10^{15}$ - $10^{20}$ Mx)。极区的磁通量的高端比宁静太阳的大一个数量级,接近孔隙的数量级。几乎所有大的贴片($ \geq 10^{18}$ Mx)具有相同的极性,而较小的贴片具有两种极性的公平平衡。因此,整个极区的极性仅由大的磁集中决定。在当前太阳活动周期的缓慢上升阶段,极地地区的净通量明显减少。北极地区的减少速度比南极地区快。净通量的减少是由于大通量集中的数量和大小减少以及低纬度出现极性相反的斑块造成的。相比之下,我们没有看到与较小的补丁($ < 10^{18}$ Mx)和水平磁场在2008- 2012年期间的磁通量的时间变化。

英文摘要:

We have been monitoring yearly variation in the Sun's polar magnetic fields with the Solar Optical Telescope aboard {\it Hinode} to record their evolution and expected reversal near the solar maximum. All magnetic patches in the magnetic flux maps are automatically identified to obtain the number density and magnetic flux density as a function of th total magnetic flux per patch. The detected magnetic flux per patch ranges over four orders of magnitude ($10^{15}$ -- $10^{20}$ Mx). The higher end of the magnetic flux in the polar regions is about one order of magnitude larger than that of the quiet Sun, and nearly that of pores. Almost all large patches ($ \geq 10^{18}$ Mx) have the same polarity, while smaller patches have a fair balance of both polarities. The polarity of the polar region as a whole is consequently determined only by the large magnetic concentrations. A clear decrease in the net flux of the polar region is detected in the slow rising phase of the current solar cycle. The decrease is more rapid in the north polar region than in the south. The decrease in the net flux is caused by a decrease in the number and size of the large flux concentrations as well as the appearance of patches with opposite polarity at lower latitudes. In contrast, we do not see temporal change in the magnetic flux associated with the smaller patches ($ < 10^{18}$ Mx) and that of the horizontal magnetic fields during the years 2008--2012.

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。

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