Microwave Negative Bursts as Indications of Reconnection Between Eruptive Filaments and a Large-Scale Coronal Magnetic Environment

Low-temperature plasma ejected in solar eruptions can screen active regions as well as quiet solar areas. Absorption phenomena can be observed in microwaves as "negative bursts" and in various spectral domains We analyze two very different recent events with such phenomena, and present an updated systematic view of solar events associated with negative bursts. Related filament eruptions can be normal, without essential changes of shape and magnetic configuration, and "anomalous." The latter are characterized by disintegration of an eruptive filament and dispersal of its remnants as a cloud over a large part of the solar disk. Such phenomena can be observed as giant depressions in the HeII 304 angstrom line. One of possible scenarios for an anomalous eruption is proposed in terms of reconnection of the filament's internal magnetic fields with an external large-scale coronal surrounding.