The thermal X-ray flare plasmaFollowing a review of current observational and theoretical knowledge of the approximately 10 to the 7th K plasma emitting the thermal soft X-ray bursts accompanying every H alpha solar flare, the fundamental physical problem of the plasma, namely the formation and evolution of the observed X-ray arches, is examined. Extensive Skylab observations of the thermal X-ray plasmas in two large flares, a large subflare and several compact subflares are analyzed to determine plasma physical properties, deduce the dominant physical processes governing the plasma and compare large and small flare characteristics. Results indicate the density of the thermal X-ray plasma to be higher than previously thought (from 10 to the 10th to 10 to the 12th/cu cm for large to small flares), cooling to occur radiatively as much as conductively, heating to continue into the decay phase of large flares, and the mass of the thermal X-ray plasma to be supplied primarily through chromospheric evaporation. Implications of the results for the basic flare mechanism are indicated.
Document ID
19800052863
Acquisition Source
Legacy CDMS
Document Type
Other - Collected Works
Authors
Moore, R. (California Institute of Technology; Big Bear Solar Observatory Pasadena, Calif., United States)
Mckenzie, D. L. (Aerospace Corp. Space Sciences Laboratory, El Segundo, Calif., United States)
Svestka, Z. (Space Research Astronomical Observatory, Utrecht, Netherlands; California, University La Jolla, Calif., United States)
Widing, K. G. (California Inst. of Tech. Pasadena, CA, United States)
Dere, K. P. (U.S. Navy, Naval Research Laboratory, Washington D.C., United States)
Antiochos, S. K. (Stanford University Stanford, Calif., United States)
Dodson-Prince, H. W. (McMath-Hulbert Observatory Pontiac, Mich., United States)
Hiei, E. (Tokyo Astronomical Observatory Mitaka, Japan)
Krall, K. R. (Alabama, University Huntsville, Ala., United States)
Krieger, A. S. (American Science and Engineering, Inc.)