标题： 太阳耀斑足点处的电子再加速 显示英文标题

标题： Electrons re-acceleration at the footpoints of Solar Flares

摘要： Hinode 的观测揭示了太阳色球层具有非常动态和复杂的性质。 这需要重新审视这样一种假设：即太阳耀斑的色球层足点区域只是加速粒子因碰撞而损失能量的地方。 传统观点认为电子在环状结构的日冕部分被加速，然后传播到足点区域，在那里损失能量并发射出观测到的硬 X 射线。 越来越多的观测证据挑战了这一假设。 我们回顾了反对这一假设的证据，并提出了新的局部再加速厚靶模型（LRTTM），其中电子在足点区域除了经历通常的碰撞损失外，还会获得额外的再加速。 这种模型可能为太阳硬 X 射线爆发源的“标准”碰撞厚靶注入模型（TTM）（Brown 1971）提供了一种替代方案，所需的电子数量更少，并解决了 TTM 解释中的一些近期问题。 我们探讨了可能导致这种再加速的不同情景，并展示了其中一个情景的数值结果。 显示英文摘要

摘要： Hinode's observations revealed a very dynamic and complex chromosphere. This require revisiting the assumption that the chromospheric footpoints of solar flares are areas where accelerated particles only lose energy due to collisions. Traditionally electrons are thought to be accelerated in the coronal part of the loop, then travel to the footpoints where they lose their energy and radiate the observed Hard X-ray. Increasing observational evidence challenges this assumption. We review the evidence against this assumption and present the new Local Re-acceleration Thick Target Model (LRTTM) where at the footpoints electrons receive a boost of re-acceleration in addition to the usual collisional loses. Such model may offer an alternative to the 'standard' collisional thick target injection model (TTM) (Brown 1971) of solar HXR burst sources, requiring far fewer electrons and solving some recent problems with the TTM interpretation. We look at the different scenarios which could lead to such re-acceleration and present numerical results from one of them.