标题： 跃迁时的日冕喷发：微类星体的常见行为？ 显示英文标题

标题： Ejection of the corona at State transitions: a common behaviour in microquasars?

摘要： 大多数微类星体爆发的开始由低硬态（LHS）和高软态（HSS）之间的状态过渡来表征。除了剧烈的能谱和时变变化外，这种过渡通常显示出一种在射电波段可探测到的离散喷射事件。然而，被喷射物质的确切性质以及这些现象产生的机制仍有待揭示。近期对多个源的同步射电和X射线观测表明，喷射物质具有日冕的性质。在GRS 1915+105、XTE J1550-564和GX 339-4于2002年的爆发案例中，在射电波段检测到喷射之前，康普顿分量的流量急剧下降。最后，在H1743-322的情况下，在状态过渡之前日冕中发生了剧烈的物理变化，这与该介质部分消失相一致。因此，至少有4个微类星体的行为表明在状态过渡期间存在日冕喷射，这一特性还有待在其他可用源中得到证实（或否定）。 显示英文摘要

摘要： The onset of most microquasar outbursts is characterized by a state transition between a Low/Hard State (LHS) and a High/Soft State (HSS). Besides drastic spectral and timing changes, this transition often shows a discrete ejection event detectable in the radio range. However, the exact nature of the ejected material and the mechanisms that give birth to these phenomena are yet to be unraveled. Recent simultaneous radio and X-ray observations on several sources point to a coronal nature of the ejected material. In the cases of GRS 1915+105, XTE J1550-564, and the 2002 outburst of GX 339-4, the flux of the Compton component decreases sharply just before an ejection is detected in the radio range. Finally, in the case of H1743-322, drastic physical changes occurred in the corona just before the state transition, compatible with the disappearance of part of this medium. Thus, the behaviour of at least 4 microquasars points in the direction of an ejection of the corona at the state transition, feature that is yet to be confirmed (or infirmed) in the case of other available sources.