Measuring Physical Parameters of CMES

In earlier work using eclipse observations, we have demonstrated that coronal electron density, electron temperature and their bulk flow speed can be measured. We have recently extended the associated modeling to include the passage of a CME, and we describe the preliminary results. The electron temperature in the solar corona determines the amount of Doppler broadening of the solar spectrum as it Thomson scatters off the coronal electrons. The outward flow of the coronal electrons from the solar surface causes the coronal electrons to see a red-shifted Sun and determines the amount of red-shift in the K-coronal spectrum. Thus, the intensity, smoothness and red-shift of the K-coronal spectrum along any given line of sight provide a measure of the electron density, electron temperature and electron bulk flow speed, respectively, along that line of sight. Likewise, the passing of a CME across a line of sight in the ambient corona will alter the shape of the K-coronal spectrum with respect to the ambient background.