Comparison of the properties of long‐lasting and impulsive type IV solar radio bursts with fine structures
Comparison of the properties of long‐lasting and impulsive type IV solar radio bursts with fine structures
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具有精细结构的持久和脉冲 IV 型太阳射电爆发的特性比较
DOI：
10.1029/2000rs002451
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
P. Zlobec
中科院分区：
文献类型：
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作者：
G. Chernov;M. Poquérusse;J. Bougeret;P. Zlobec
我们考虑的精细结构（主要是斑马图案）和连续辐射在某些IV型射电爆发的光学和X射线特征的源位置。为了完整性，在不同的天文台记录的精细结构的动态光谱相互比较，并与记录的圆形左，右偏振在单一的频率。我们分析了三种持续时间较长的IV型事件（事件1989年3月12日，1990年6月5日，和1992 02 17）的特点是没有微波爆发和大耀斑和两个脉冲事件（1990 - 06 - 11和1994 - 10 - 25）由II型爆发和相当短的IV型连续体形成，它们与Hα耀斑和微波爆发密切相关。所有这些事件都与活跃的细丝有关。作为更复杂事件（包括脉冲性和持续时间较长的IV型爆发）的一个例子，我们考虑了事件1997 11 04。在这三个持续时间较长的事件中，精细结构的一个普遍特点是斑马图案和脉动的长期演化（2-3小时），这证明了在日冕物质抛射逃逸后磁拱恢复期间，垂直电流片中存在快速粒子的重复加速。脉冲事件源的磁位形必须相当接近斜耀斑电流片。复杂事件可以有两个步骤的演变：前者涉及低耀斑环的重联，而后者涉及更高日冕的重联。
We consider source positions of fine structures (mainly of zebra pattern) and of continuum emission in some type IV radio bursts with respect to optical and X‐ray features. For completeness, dynamic spectra of fine structures recorded in different observatories were compared with each other and with records of circular left and right polarization at single frequencies. We analyzed three long‐lasting type IV events (events 1989 03 12, 1990 06 05, and 1992 02 17) that were characterized by the absence of microwave bursts and big flares and two impulsive events (events 1990 06 11 and 1994 10 25) formed by type II bursts and by rather short living type IV continuum in close relation to Hα flares and microwave bursts. All those events were connected with active filaments. As an example of more complex events, including both impulsive and long‐lasting type IV bursts, event 1997 11 04 is considered. A general peculiarity of fine structures in the three long‐lasting events is the long‐term evolution of zebra patterns and pulsations (2–3 hours), which testifies to the presence of repeated acceleration of fast particles in vertical current sheets during the restoration of magnetic arches after the escape of coronal mass ejections. The magnetic configurations in the source of the impulsive events must be rather close to oblique flare current sheets. Complex events can have a two‐step evolution: The former regards the reconnection in low flaring loops, while the latter is related to the reconnection in the higher corona.