Interaction of a collisionless conduction front with the chromosphere and solar hard X-ray bursts

Abstract

view Abstract Citations (43) References (24) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Interaction of a collisionless conduction front with the chromosphere and solar hard X-ray bursts Smith, D. F. ; Harmony, D. W. Abstract The interaction of a collisionless conduction front with the transition region and chromosphere is investigated in a one-dimensional fluid approach as an explanation of elementary flare bursts in hard X-rays. It is shown that, for finite energy injection times, material boiled off of the chromosphere rises into the corona and eventually quenches the X-ray emission. This provides an acceptable explanation of elementary flare bursts with many testable predictions. Softer (10-20 keV) X-rays should come primarily from near the chromosphere, while harder (90-100 keV) X-rays should come primarily from higher in the corona. Ion heating to 108 K and upward mass motions to 1000 km s-1 should be observed. Limitations of the analysis resulting from its fluid character and implications for testable predictions are discussed. It is emphasized that, although the efficiency of this thermal model is only slightly larger than a nonthermal model for an initial density of 2.6 × 1010 cm-3, it is much easier from the point of view of plasma physics to heat a plasma than to accelerate a significant fraction of its electrons. Publication: The Astrophysical Journal Pub Date: January 1982 DOI: 10.1086/159602 Bibcode: 1982ApJ...252..800S Keywords: Chromosphere; Collisionless Plasmas; Plasma Interactions; Solar Flares; Solar X-Rays; Bursts; Electron Acceleration; Ion Production Rates; Ion Temperature; Plasma Heating; Plasma Physics; Radiative Transfer; Stellar Models; X Ray Astronomy; Solar Physics full text sources ADS |