Radio signatures of a fast coronal mass ejection development on November 6, 1997

The Oporto radiospectrograph and the Nancay radioheliograph recorded a radi o event on November 6, 1997, closely related in time with a flare on Nation al Oceanic and Atmospheric Administration (NOAA) active region 8100. At the beginning: of the event the radio sources are located on a rather small vo lume in the vicinity of the flare site. In a timescale df only a few minute s the radio emission sites spread over a large volume in the corona, coveri ng a range of 100 degrees in heliolatitude. During the period of the radio event the Large Angle and Spectrometric Coronagraph (LASCO) on board the So lar and Heliospheric Observatory (SOHO) observed an extremely fast coronal mass ejection (CME), with a velocity around 2000 km s(-1) This CME presents the particularity of having a fast lateral expansion, giving it a shape re miniscent of a "coat hanger." There is a very good association between the latitudinal extent and time development of the CME seen by LASCO and the ra dio sources recorded by the radio instruments.