mi017.watari07 Posted: 09-Aug-96 Updated: Events specified: see text
S. Watari (Communications Research Lab.) T. Watanabe (Ibaraki University)
A large prominence eruption was simultaneously observed by soft X-ray, radio, and H-alpha at the north-east limb on 30-31 July 1992. Hanaoka et al. (1994) reported about this event in detail. According to Hanaoka et al. (1994), the radio (17 GHz) and H-alpha observations showed a good correspondence. The arch expanding with a velocity of approximately 100 km/s was detected by the radio and H-alpha. However, the observed soft X-ray arcade located underneath the radio and H-alpha arch and kept approximately the same height. This observation may suggest that the soft X-ray arcade is remnant of the coronal mass ejection.
Interplanetary shock associated with the event was observed at the Earth at 0109 UT and 1408 UT on 4 August 1992. The in situ shock velocity was approximately 380 km/s and the geomagnetic storm followed the shock. The magnetic flux rope structure was found in the interplanetary magnetic field.
In this event the flux rope was lunched gently and the shock velocity at the Earth was slow. The magnetic filed of the flux rope disturbed the geomagnetic field. This event notes that the magnetic field, which the eruption carries with, is an important factor of the goeffectiveness.
Reference Hanaoka et al., 1994, Simultaneous observation of a prominence eruption followed by a coronal arcade formation in radio, soft X-rays, and Ha, Publ. Astron. Soc. Japan, 46, 205-216.