arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1701.06286astro-ph.SR
收藏

由非热电子直接产生的白光耀斑的IRIS、Hinode、SDO和RHESSI观测

IRIS, Hinode, SDO, and RHESSI observations of a white light flare produced directly by non-thermal electrons

Kyoung-Sun Lee, Shinsuke Imada, Kyoko Watanabe, Yumi Bamba, David H. Brooks

摘要:

2014年10月22日14:02 UT,AR 12192发生X1.6耀斑,由Hinode,IRIS,SDO和RHESSI观测到。我们分析了一个明亮的内核,产生了白光(WL)耀斑与连续增强和硬X射线(HXR)峰。利用IRIS和Hinode/EIS的光谱观测,我们测量了色球和日冕亮核等离子体性质的时间变化。我们发现,爆炸蒸发时观察到的WL发射发生,即使在较热的线的强度增强是相当弱的。WL发射、HXR峰和蒸发流的时间相关性表明WL发射是由加速电子产生的。为了理解白光发射过程,我们计算了由非热电子沉积的能量通量(由RHESSI观察到),并将其与由IRIS观察到的色球线(Mg II三重态)估计的耗散能量进行比较。在30 ~ 40 keV的低能截止能量下,在厚靶模型下,非热电子的能流约为3 ~ 7.7 × 10^(10)erg cm^(-2)s^(-1)。利用Mg II副谱线测量色球层温度变化,估算出的能流约为4.6 - 6.7 × 10(9)erg cm^(-2)s^(-1):约为沉积能量的6-22%。这种估计的能量通量的比较意味着连续增强是由非热电子直接产生的。

英文摘要:

An X1.6 flare occurred in AR 12192 on 2014 October 22 at 14:02 UT and was observed by Hinode, IRIS, SDO, and RHESSI. We analyze a bright kernel which produces a white light (WL) flare with continuum enhancement and a hard X-ray (HXR) peak. Taking advantage of the spectroscopic observations of IRIS and Hinode/EIS, we measure the temporal variation of the plasma properties in the bright kernel in the chromosphere and corona. We found that explosive evaporation was observed when the WL emission occurred, even though the intensity enhancement in hotter lines is quite weak. The temporal correlation of the WL emission, HXR peak, and evaporation flows indicate that the WL emission was produced by accelerated electrons. To understand the white light emission process, we calculated the energy flux deposited by non- thermal electrons (observed by RHESSI) and compared it to the dissipated energy estimated from a chromospheric line (Mg II triplet) observed by IRIS. The deposited energy flux from the non-thermal electrons is about 3 ~ 7.7 X 10^(10) erg cm^(-2) s^(-1) for a given low energy cut-off of 30 ~ 40 keV, assuming the thick target model. The energy flux estimated from the temperature changes in the chromosphere measured using the Mg II subordinate line is about 4.6 - 6.7 X 10(9) erg cm^(-2) s^(-1): ~6-22% of the deposited energy. This comparison of estimated energy fluxes implies that the continuum enhancement was directly produced by the non-thermal electrons.

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。

↑