HR: 1330h
AN: SH22A-0188    [PDF]
TI: Coordinated UVCS/SOHO and VLA Observations of the Solar Corona
AU: * Miralles, M P
EM: mmiralles@cfa.harvard.edu
AF: Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS-50, Cambridge, MA 02138 United States
AU: Cranmer, S R
EM: scranmer@cfa.harvard.edu
AF: Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS-50, Cambridge, MA 02138 United States
AU: Raymond, J C
EM: jraymond@cfa.harvard.edu
AF: Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS-50, Cambridge, MA 02138 United States
AU: Spangler, S R
EM: srs@vesta.physics.uiowa.edu
AF: Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52242 United States
AU: Kohl, J L
EM: jkohl@cfa.harvard.edu
AF: Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS-50, Cambridge, MA 02138 United States
AB: Coordinated UVCS/SOHO and VLA coronal observations took place during August 16--19, 2003. The radio source 3C 228 passed behind a streamer in the northeast at a heliocentric distance of about 7 solar radii, and behind the north coronal hole at about 4 solar radii in the latter part of the radio observation. The goal of this campaign is to combine the analysis of radio polarimetric sounding measurements of the corona with ultraviolet spectroscopy of the same regions, in order to obtain qualitatively new information about the properties of the solar coronal plasma. The Ultraviolet Coronagraph Spectrometer (UVCS) aboard SOHO observed O VI (103.2 and 103.7 nm) and H I Lyman alpha (121.6 nm) emission lines to determine kinetic temperatures, average densities and outflow speeds in the corona. UVCS observations provide unique information on the heating and acceleration processes in the corona. The Very Large Array (VLA) observations reveal the Faraday rotation of polarized radio waves due to passage through the magnetized plasma of the corona. These measurements provide limits on the coronal magnetic field strength and constrain the properties of magnetohydrodynamic (MHD) waves. Radio propagation techniques are a useful complementary tool to ultraviolet coronagraphic spectroscopy in determining the physical processes that are responsible for the heating of the extended corona and the acceleration of the solar wind. This work is supported by NASA under Grant NAG5-12865 to the Smithsonian Astrophysical Observatory, by the Italian Space Agency and by PRODEX (Swiss contribution).
DE: 2149 MHD waves and turbulence
DE: 2164 Solar wind plasma
DE: 7509 Corona
DE: 7534 Radio emissions
DE: 7549 Ultraviolet emissions
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting