Electric Potentials and Energy Fluxes Available for Particle Acceleration by Alfvenons in the Solar Corona

• Published in: Astrophysical journal. Letters Vol. 680; no. 2; pp. L153 - L156
• Main Authors: Stasiewicz, K, Ekeberg, J
• Format: Journal Article
• Language: English
• Published: Chicago, IL IOP Publishing 20.06.2008; University of Chicago Press
• Subjects: acceleration of particles; Astronomy; Earth, ocean, space; Exact sciences and technology; Fysik; gamma rays; MHD; NATURAL SCIENCES; NATURVETENSKAP; Physics; Sun : corona; Sun : flares; Sun : X-rays; Potential energy; Solar corona; Electric potential; acceleration of particles-MHD-Sun: corona-Sun: flares-Sun: X-rays; gamma rays; Gamma radiation; Particle acceleration; Sun; Energy transfer
• ISSN: 1538-4357; 0004-637X; 2041-8213; 1538-4357
• DOI: 10.1086/589878

We show that solitary wave solutions of the one- and two-fluid MHD equations, here called alfvenons, represent two types of electric field structures with negative or positive potentials that can explain the acceleration of particles in the solar corona. Negative potentials are created self-consistently by fast alfvenons and can reach hundreds of kilovolts, which could accelerate the electrons that produce X-ray emissions during flares. Slow alfvenons create positive potential structures of a few kV that accelerate solar wind ions. These alfvenons can be powered by irregular plasma flows in the photosphere and chromosphere, as well as by time-varying magnetic fields during reconnection events at the tops of coronal loops. Similar alfvenon structures are observed in the terrestrial magnetosphere, where they accelerate particles related to aurorae.