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arXiv 1507.04075astro-ph.SR
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Hinode观测到的太阳极地喷流的光球丰度

Photospheric Abundances of Polar Jets on the Sun Observed by Hinode

Kyoung-Sun Lee, David H. Brooks, Shinsuke Imada

摘要:

在太阳的两极地区,许多喷流在X射线波长下被探测到,沿着喷流喷射的等离子体被认为是快速太阳风的质量来源。从磁层的现场测量中发现,快太阳风具有光球丰度,而慢太阳风具有日冕丰度。因此,我们研究了极地喷流的丰度,以确定它们是否与快速太阳风的丰度相同。在这项研究中,我们选择了22个喷流在极地地区观测的日出/EIS(EUV成像光谱仪)和XRT(X射线望远镜)同时在2007年11月1日至3日。我们利用EIS谱计算了高(S)和低(Si,Fe)FIP元素之间的强度比的第一电离势(FIP)偏置因子。极区喷流的FIP偏置因子值在0.7-1.9之间,其中75个$\%$的偏置因子值在0.7-1.5之间,表明极区喷流具有与快速太阳风相似的光球丰度。结果与光球等离子体出现并被迅速喷入快风的重联喷流模型一致。

英文摘要:

Many jets are detected at X-ray wavelengths in the Sun's polar regions, and the ejected plasma along the jets has been suggested to contribute mass to the fast solar wind. From in-situ measurements in the magnetosphere, it has been found that the fast solar wind has photospheric abundances while the slow solar wind has coronal abundances. Therefore, we investigated the abundances of polar jets to determine whether they are the same as that of the fast solar wind. For this study, we selected 22 jets in the polar region observed by Hinode/EIS (EUV Imaging Spectrometer) and XRT (X-Ray Telescope) simultaneously on 2007 November 1-3. We calculated the First Ionization Potential (FIP) bias factor from the ratio of the intensity between high (S) and low (Si, Fe) FIP elements using the EIS spectra. The values of the FIP bias factors for the polar jets are around 0.7-1.9, and 75$\%$ of the values are in the range of 0.7-1.5, which indicates that they have photospheric abundances similar to the fast solar wind. The results are consistent with the reconnection jet model where photospheric plasma emerges and is rapidly ejected into the fast wind.

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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