论文标题
在太阳活性区域中微纤维的nustar观察
NuSTAR Observation of a Minuscule Microflare in a Solar Active Region
论文作者
论文摘要
我们提出了有史以来最弱的活性区域（AR）微片之一的X射线成像光谱。微叶片发生在2018年9月9日的$ \ sim $ 11：04 UT，我们使用核光谱望远镜阵列（Nustar）和太阳能天文台的大气成像组件（SDO/AIA）对其进行了研究。在2.5-7 keV中清楚地观察了微叶片，并以Nustar和Fe XVIII发射从94 $ \ unicode {x212b} $ sdo/aia通道的较热组件得出。我们估计，该事件的数量级比A的三个数量级低，其能量为1.1 $ \ times $ 10 $^{26} $ erg。它达到6.7 mk的温度，排放量为8.0 $ \ times $ 10 $^{43} $ cm $^{ - 3} $。未检测到非热发射，而是我们确定了这种排放的上限。我们介绍了文献中AR微叶片的最低热能估计值，该估计位于仍被认为是X射线微叶片的下限。
We present X-ray imaging spectroscopy of one of the weakest active region (AR) microflares ever studied. The microflare occurred at $\sim$11:04 UT on 2018 September 9 and we studied it using the Nuclear Spectroscopic Telescope ARray (NuSTAR) and the Solar Dynamic Observatory's Atmospheric Imaging Assembly (SDO/AIA). The microflare is observed clearly in 2.5-7 keV with NuSTAR and in Fe XVIII emission derived from the hotter component of the 94 $\unicode{x212B}$ SDO/AIA channel. We estimate the event to be three orders of magnitude lower than a GOES A class microflare with an energy of 1.1$\times$10$^{26}$ erg. It reaches temperatures of 6.7 MK with an emission measure of 8.0$\times$10$^{43}$ cm$^{-3}$. Non-thermal emission is not detected but we instead determine upper limits to such emission. We present the lowest thermal energy estimate for an AR microflare in literature, which is at the lower limits of what is still considered an X-ray microflare.
