HR: 11:10h
AN: SH41D-04    [PDF]
TI: The Coronal Magnetic Field, Signatures of Coronal Holes and Silicon Nanometer Dust Grains
AU: * Habbal, S R
EM: sdh@aber.ac.uk
AF: University of Wales at Aberystwyth, Institute of Mathematical and Physical Sciences, Aberystwyth, SY23 3BZ United Kingdom
AU: * Habbal, S R
EM: sdh@aber.ac.uk
AF: Harvard-Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138 United States
AU: Arndt, M B
EM: MArndt@bridgew.edu
AF: Bridgewater State College, Department of Physics, Bridgewater, MA 02325 United States
AU: Nayfeh, M
EM: m-nayfeh@mail.physics.uiuc.edu
AF: University of Illinois at Urbana-Champaign, Department of Physics, Urbana, IL 61801 United States
AU: Arnaud, J
EM: arnaud@ast.obs-mip.fr
AF: Observatoire Midi-Pyrenees, 14 Avenue d'Edouard Belin, Toulouse, F-31400 France
AU: Woo, R
EM: richard.woo@jpl.nasa.gov
AF: Jet Propulsion Lab, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AB: The near-infrared part of the solar spectrum is where some of the strongest coronal forbidden lines are formed. Polarized emission in these lines offers the only tool currently known for the inference of the direction of the coronal magnetic field. The first successful observations of the polarized emission from the 1074.7 nm Fe XIII line were made by Eddy, Lee and Emerson during the eclipse of 1966 in a limited region of the corona. The only subsequent polarimetric observations in this line were carried out with the coronagraph at Sac Peak from 1977-1980. We report on the first successful polarimetric measurements of the 1074.7 nm line in a field of view extending out to 3.5 solar radii which were made during the total solar eclipse of 21 June 2001. In addition to confirming earlier results of the predominance of a radial direction of the coronal magnetic field, these measurements yielded the first polarimetric signature of coronal holes, and the signature of nanometer size dust grains in the corona. These observations suggest the existence of a rich coronal spectrum of narrow lines in the near-infared produced by the fluorescence of silicon nanometer dust grains in the inner corona. This work was funded by NSF grant ATM-0003661 and NASA grant NAG5-10873 to the Smithsonian Astrophysical Observatory.
DE: 2129 Interplanetary dust
DE: 2169 Sources of the solar wind
DE: 7509 Corona
DE: 7511 Coronal holes
DE: 7524 Magnetic fields
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting