论文标题
首次检测太阳潮的度量排放
First detection of metric emission from a solar surge
论文作者
论文摘要
我们报告了通过Nançay射线光（NRH），立体声和其他仪器观察到的电涌的度量无线电发射的首次检测。在先前出版物中描述的M9复合事件Sol21-02-012t11：25：00的晚期阶段观察到发射，并与二级能量释放有关，并在Stereo304Å图像中也观察到：没有可检测的软X射线发射。立体声图像的三角剖分允许在中央子午线附近使用NRH来源鉴定激增。电涌的无线电发射分为两个阶段，由两个来源组成，一个源位于浪涌底部附近，显然是在能量释放部位或附近，另一个位于潮流的上部。这些在445.0至约300MHz的频率范围内最好可见，而在较低频率下观察到了不同性质的光谱成分。在两个阶段的两个来源中都检测到了下秒的变化，相对于下部的0.2-0.3s延迟了上部源，表明超亮速度。如果上源的发射是由于辐射散射从涌动底部的源散射，则可以解释这种效果。此外，无线电发射显示出脉动和尖峰的迹象。我们讨论了较低无线电源的缓慢变化分量的可能发射机制。陀螺仪发射在事件第二阶段开始时观察到的总强度光谱的特征相当很好，但在其他情况下未能再现观察到的圆极化的高度以及光谱。另一方面，基本的IV型等离子体发射可以解释动态光谱中的高极化和精细结构。此外，从立体声A中可以看出，它在天空平面上提供了预计的无线电源位置。考虑到所有内容，我们建议使用低强度陀螺仪成分的IV类样等离子体发射作为最合理的机制。
We report the first detection of metric radio emission from a surge, observed with the Nançay Radioheliograph (NRH), STEREO and other instruments. The emission was observed during the late phase of the M9 complex event SOL2010-02-012T11:25:00, described in a previous publication and was associated with a secondary energy release, also observed in STEREO 304 Å images: there was no detectable soft X-ray emission. Triangulation of the STEREO images allowed the identification of the surge with NRH sources near the central meridian. The radio emission of the surge occurred in two phases and consisted of two sources, one located near the base of the surge, apparently at or near the site of energy release, and another in the upper part of the surge; these were best visible in the frequency range of 445.0 to about 300MHz, whereas a spectral component of different nature was observed at lower frequencies. Sub-second time variations were detected in both sources during both phases, with 0.2-0.3s a delay of the upper source with respect to the lower, suggesting superluminal velocities. This effect can be explained if the emission of the upper source was due to scattering of radiation from the source at the base of the surge. In addition, the radio emission showed signs of pulsations and spikes. We discuss possible emission mechanisms for the slow time variability component of the lower radio source. Gyrosynchrotron emission reproduced fairly well the characteristics of the observed total intensity spectrum at the start of the second phase of the event, but failed to reproduce the high degree of the observed circular polarization as well the spectra at other instances. On the other hand, type IV-like plasma emission from the fundamental could explain the high polarization and the fine structure in the dynamic spectrum; moreover, it gives projected radio source positions on the plane of the sky, as seen from STEREO-A, near the base of the surge. Taking everything into consideration, we suggest type IV-like plasma emission with a low intensity gyrosynchrotron component as the most plausible mechanism.
