Multi-wave band SMM-VLA observations of an M2 flare and an associated coronal mass ejection

• Published in: The Astrophysical journal Vol. 378; no. 1; pp. 360 - 371
• Main Authors: Willson, Robert F., Lang, Kenneth R., Schmelz, Joan T., Gonzalez, Raymond D., Smith, Kermit L.
• Format: Journal Article
• Language: English
• Published: Legacy CDMS University of Chicago Press 01.09.1991
• Subjects: Astronomy; Earth, ocean, space; Exact sciences and technology; Flares, bursts, and related phenomena; Solar Physics; Solar system; Solar corona; X ray observation; Hα line; X ray burst; Coronal mass ejection; VLA observation; Active region; Satellite observation; Radio interferometric observation; Sun; Radio burst; Solar burst; Solar flare; Radio radiation; Solar X ray
• ISSN: 0004-637X; 1538-4357
• DOI: 10.1086/170436

Results are presented of observations of an M2 flare and an associated coronal mass ejection CME by instruments on the SMM as well as by the VLA and other ground-based observatories on September 30, 1988. The multiwave band data show a gradual slowly changing event which lasted several hours. The microwave burst emission was found to originate in compact moderately circularly polarized sources located near the sites of bright H-alpha and soft X-ray emission. These data are combined with estimates of an electron temperature of 1.5 x 10 to the 7th K and an emission measure of about 2.0 x 10 to the 49th/cu cm obtained from Ca XIX and Fe XXV spectra to show that the microwave emission can be attributed to thermal gyrosynchrotron radiation in regions where the magnetic field strength is 425-650 G. The CME acceleration at low altitudes is measured on the basis of ground- and space-based coronagraphs.