AAS 204th Meeting, June 2004
Session 46 Plasma Astrophysics of Coronae: Solar, Stellar and Accretion Disk
Topical Session, Tuesday, June 1, 2004, 2:30-4:00pm, 4:15-6:00pm, 710/712

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[46.04] Particle Acceleration in Impulsive Solar Flares

J. A. Miller (UAH)

Solar flares are among the most interesting phenomena in the solar system, releasing up to 1032 ergs of energy on timescales ranging from several seconds to several minutes. Much of this energy appears in the form of suprathermal ions and electrons, which are accelerated out of the background thermal distributions and into the relativistic regime in about 1 second. These energetic particles subsequently produce a host of secondary emissions, ranging from radio waves to nuclear de-excitation gamma-ray lines, as well as escape into space where they can be directly observed. The neutral emissions and the interplanetary particles are valuable diagnostics of the particle acceleration mechanism. In particular, ion abundance enhancements, first observed in the interplanetary particles but then later inferred from gamma-ray line spectroscopy, are important clues to the nature of the acceleration mechanism, as are RHESSI observations of X- and gamma-ray emissions being preferentially produced in shorter and longer loops, respectively.

After reviewing the pertinent observational data, we will present the basic requirements that any solar flare particle acceleration theory must satisfy. We will argue that the most viable unified particle acceleration theory is stochastic resonant acceleration by cascading MHD turbulence.

The author(s) of this abstract have provided an email address for comments about the abstract: MillerJA@UAH.edu

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