Soft X-ray, microwave, and hard X-ray emission from a solar flare - Implications for electron heating and acceleration in current channels

Journal Article · Sun Oct 01 04:00:00 EDT 1989 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/167975· OSTI ID:5126062

Holman, G D; Kundu, M R; Kane, S R ^[1]

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1. NASA, Goddard Space Flight Center, Greenbelt, MD (USA) Maryland Univ., College Park (USA) NASA, Space Physics Div., Washington, DC (USA) California Univ., Berkeley (USA)

The soft X-ray, microwave, and hard X-ray emissions from the solar flare of May 14, 1980 are studied. The flare consists of a gradual component in soft X-rays and microwaves and a superposed impulsive burst accompanied by hard X-ray emission. The impulsive phase of the flare appears in the soft X-ray emission as a temperature spike and as an increased rate of energy dissipation into the plasma. A new, spatially and spectrally distinct, microwave component appears during the impulsive burst. The data are interpreted in terms of Joule heating and the electric field acceleration of electrons in one or more current sheets. It is found that all three emissions can be generated with sub-Dreicer electric fields. The soft X-ray emitting plasma can be heated by a single current sheet only if the resistivity in the sheet is well above the classical, collisional resistivity. Conditions are also given for the hard X-ray emission to be from nonthermal electrons with classical resistivity. 24 refs.

• OSTI ID: 5126062
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 345; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCELERATION
ELECTRIC HEATING
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
ENERGY LOSSES
FERMIONS
FLUID MECHANICS
HARD X RADIATION
HEATING
HYDRODYNAMICS
IONIZING RADIATIONS
LEPTONS
LOSSES
MAGNETOHYDRODYNAMICS
MECHANICS
MICROWAVE RADIATION
RADIATIONS
RADIOWAVE RADIATION
RESISTANCE HEATING
SOFT X RADIATION
SOLAR ACTIVITY
SOLAR ELECTRONS
SOLAR FLARES
SOLAR PARTICLES
SOLAR RADIATION
SOLAR RADIO BURSTS
STELLAR RADIATION
X RADIATION