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Solar radio bursts of spectral type II, coronal shocks, and optical coronal transientsAn examination is presented of the association of solar radio bursts of spectral type II and coronal shocks with solar flare ejecta observed in H-alpha, the green coronal line, and white-light coronagraphs. It is suggested that fast-moving optical coronal transients should for the most part be identified with piston-type phenomena well behind the outward-traveling shock waves that generate type II radio bursts. A general model is presented which relates type II radio bursts and coronal shocks to optically observed ejecta and consists of three main velocity regimes: (1) a quasi-hemispherical shock wave moving outward from the flare at speeds of 1000-2000 km/sec and Alfven Mach number of about 1.5; (2) the velocity of the piston driving the shock, on the order of 0.8 that of the shock; and (3) the regime of the slower-moving H-alpha ejecta, with velocities of 300-500 km/sec.
Document ID
19810064712
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Maxwell, A. (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Dryer, M. (NOAA, Environmental Research Laboratories, Boulder CO, United States)
Date Acquired
August 11, 2013
Publication Date
October 1, 1981
Publication Information
Publication: Solar Physics
Volume: 73
Subject Category
SOLAR PHYSICS
Funding Number(s)
CONTRACT_GRANT: NASA ORDER S-59811
CONTRACT_GRANT: NSG-7648
CONTRACT_GRANT: NSF ATM-77-21453
Distribution Limits
Public
Copyright
Other