标题： 微波成像光谱学对重大太阳爆发缓慢上升前兆的诊断 显示英文标题

标题： Microwave Imaging Spectroscopy Diagnosis of the Slow-rise Precursor of a Major Solar Eruption

摘要： 在本信中，利用扩展欧文山谷太阳阵列的微波数据和大气成像组件的极端紫外（EUV）数据，我们首次对2022年3月30日重大日冕物质抛射（CME）的缓慢上升前导现象进行了微波成像光谱诊断。 EUV图像显示，在爆发之前，CME的前身表现为极性反转线之上的热通道，经历了缓慢上升和加热。 发现微波辐射主要沿热通道分布，高频源位于热通道的两端以及热通道下方的前导明亮环状结构上。 微波光谱分析表明，前导阶段的微波辐射主要由热辐射主导，与主阶段存在显著不同的非热成分。 这些结果支持这样的情景，即前导阶段的重联现象相比主阶段的耀斑重联显得较为温和，驱动了CME前身的积累、加热和缓慢上升，最终导致爆炸性爆发。 显示英文摘要

摘要： In this Letter, taking advantage of microwave data from the Expanded Owens Valley Solar Array and extreme-ultraviolet (EUV) data from the Atmospheric Imaging Assembly, we present the first microwave imaging spectroscopy diagnosis for the slow-rise precursor of a major coronal mass ejection (CME) on 2022 March 30. The EUV images reveal that the CME progenitor, appearing as a hot channel above the polarity inversion line, experiences a slow rise and heating before the eruption. The microwave emissions are found to mainly distribute along the hot channel, with high-frequency sources located at the ends of the hot channel and along precursor bright loops underneath the hot channel. The microwave spectroscopic analysis suggests that microwave emissions in the precursor phase are dominated by thermal emission, largely different from the main phase when a significant non-thermal component is present. These results support the scenario that the precursor reconnection, seeming to be moderate compared with the flare reconnection during the main phase, drives the build-up, heating, and slow rise of CME progenitors toward the explosive eruption.