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Schmidt & Cargill 2000
Schmidt, J.M. and Cargill, P.J. (2000). A model for accelerated density enhancements emerging from coronal streamers in Large-Angle and Spectrometric Coronagraph observations. Journal of Geophysical Research 105: doi: 10.1029/1999JA900505. issn: 0148-0227.

Recent Large-Angle and Spectrometric Coronagraph (LASCO) white light observations, ranging between 2 RS and 32 RS, trace accelerated density enhancements in the vicinity of the Sun which can be detected as enhancement in the intensity of the Thomson scattered light. One interpretation of these observed density enhancements is that they indicate moving plasmoids in the corona. Such plasmoids are accelerated away from the Sun by a Lorentz force due to the radial solar magnetic field. A model of accelerated plasmoids is presented which includes this magnetic acceleration, the Sun's gravitational attraction, and the aerodynamic drag acting on the plasmoid as it interacts with the solar wind. With reasonable choices of physical parameters the model produces velocity-height profiles close to the observed ones. Profiles for external initial Alfv¿n velocities vAe0=80, 350, and 450 km/s (external initial magnetic field Be0=0.04, 0.16, and 0.21 Gauss) at r0=5 RS approximately match the lower, the middle, and the upper range of the observed velocity profiles, respectively. Choices for the ratio of the initial plasmoid number density ni0 and the initial solar wind number density ne0 of 2i0/ne0<12 guarantee a slowly decreasing relative intensity enhancement in the range of observations. Only moderate line of sight intensity enhancements can be caused by a small and dense plasmoid. ¿ 2000 American Geophysical Union

BACKGROUND DATA FILES

Abstract

Keywords
Solar Physics, Astrophysics, and Astronomy, Solar Physics, Astrophysics, and Astronomy, Corona, Space Plasma Physics, Charged particle motion and acceleration, Space Plasma Physics, Numerical simulation studies
Journal
Journal of Geophysical Research
http://www.agu.org/journals/jb/
Publisher
American Geophysical Union
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