arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1811.03219astro-ph.SR
收藏

IRIS、Hinode和SDO观测到的小通量出现区上方的磁环

Magnetic loops above a small flux-emerging region observed by IRIS, Hinode and SDO

Zhenghua Huang

摘要:

我报告的一组磁环以上的一个区域的晚相磁通量出现IRIS,日之出和SDO的意见。环系统由许多长5- 12 \arcsec \、宽$\sim0.5$ \arcsec的移行区环线和长、宽相似的$\sim2$ \arcsec冠状环组成。虽然线圈系统由具有不同温度的线组成,但大多数单个线圈线的温度范围很窄。在环系统的中间,在过渡区出现了明显的系统蓝移,约为10\,\kms \,这与通量出现的图像一致,而在日冕中观察到了红移,约为10\,\kms \。在过渡区,环系统的非热速度小于周围区域,但在日冕中是相当的。环系统的日冕对应物的电子密度范围从$1\times10^9$ \,cm $^{-3}$到$4\times10^9$ \,cm $^{-3}$。还测量了过渡区环的电子密度,发现其值约为$5\times10^{10}$·cm $^{-3}$,比日冕环的电子密度大一个量级。与成像数据一致,来自差分发射测量技术的温度分布证实,一些环路已被加热到电晕。我们的观测表明,磁通出现的后期阶段与早期阶段有很大的不同。虽然观察到的过渡区主要是新兴的通量,这些新兴的环路可以被加热到电晕和加热(如果通过非热过程)最有可能发生后,他们到达过渡区或较低的电晕。

英文摘要:

I report on observations of a set of magnetic loops above a region with late-phase flux emergence taken by IRIS, Hinode and SDO. The loop system consists of many transition region loop threads with size of 5--12\arcsec\ in length and $\sim0.5$\arcsec in width and coronal loops with similar length and $\sim2$\arcsec width. Although the loop system consists of threads with different temperatures, most individual loop thread have temperature in a narrow range. In the middle of the loop system, it shows clear systematic blue-shifts of about 10\,\kms\ in the transition region that is consistent with a flux emerging picture, while red-shifts of about 10\,\kms\ in the corona is observed. The nonthermal velocity of the loop system are smaller than the surrounding region in the transition region but are comparable in the corona. The electron densities of the coronal counterpart of the loop system range from $1\times10^9$\,cm$^{-3}$ to $4\times10^9$\,cm$^{-3}$. Electron density of a transition region loop is also measured and found to be about $5\times10^{10}$\,cm$^{-3}$, a magnitude larger than that in the coronal loops. In agreement with imaging data, the temperature profiles derived from the differential emission measurement technique confirms that some of the loops have been heated to corona. Our observations indicate that the flux emergence in its late phase is much different from that at the early stage. While the observed transition region is dominated by emerging flux, these emerging loops could be heated to corona and the heatings (if via nonthermal processes) most likely take place only after they reaching the transition region or lower corona.

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。

↑