标题： 紫外脉动的时空演化及其与三维磁重联和粒子加速的关系 显示英文标题

标题： Spatiotemporal evolution of UV pulsations and their connection to 3D magnetic reconnection and particle acceleration

摘要： 准周期脉动（QPPs）是太阳耀斑冲动辐射的常见特征，但其驱动机制仍未解决。 我们利用SDO/AIA和Solar Orbiter/STIX研究了2023年2月24日M3.7级耀斑中的长周期（3.4分钟）QPPs，以确定其源区和驱动因素。 我们分析了覆盖耀斑带和爆发丝足点的四个子区域的紫外线和硬X射线（HXR）辐射。 我们发现这些区域内的QPP特征存在显著差异。 最强的紫外线脉动与HXR辐射高度相关，起源于南部耀斑带扩展前沿的一系列耀斑核。 相比之下，另一个扩展的带前沿没有显示出脉动。 紫外线和硬X射线源的空间一致性表明非热电子是共同驱动因素，硬X射线谱显示软-硬-软演化与脉动时间尺度相匹配。 我们还观察到来自注入到另一条丝道的等离子体的紫外线脉动，该丝道与主要耀斑核不同。 我们的结果表明，脉动的时空演化是由磁场再连接在不对称几何结构中的传播所驱动的。 我们提出，沿着拟分隔层的滑动再连接是产生和移动紫外线核的关键，可能受到另一种时变过程的调制。 显示英文摘要

摘要： Quasi-periodic pulsations (QPPs) are a common feature of impulsive solar flare emissions, yet their driving mechanism(s) remain unresolved. We study long-period (3.4 min) QPPs in the M3.7 flare on Feb 24, 2023, using SDO/AIA and Solar Orbiter/STIX to pinpoint their source and driver. We analyzed UV and HXR emissions from four subregions covering the flare ribbons and footpoints of the erupting filament. We find the QPP characteristics varied significantly across these regions. The strongest UV pulsations, which correlated strongly with HXR emissions, originated from a sequence of flare kernels at the expanding front of the southern flare ribbon. In contrast, another expanding ribbon front showed no pulsations. The spatial coincidence of UV and HXR sources points to non-thermal electrons as a common driver, with the HXR spectrum showing a soft-hard-soft evolution matching the pulsation timescale. We also observed UV pulsations from plasma injections into a separate filament channel, distinct from the main flare kernels. Our results suggest that the spatiotemporal evolution of the pulsations is driven by the propagation of magnetic reconnection in an asymmetric geometry. We propose that slipping reconnection along quasi-separatrix layers is key to generating and moving the UV kernels, potentially modulated by another time-varying process.