Coronal Mass Ejections Observed by SOHO-UVCS and MLSO

A rich database of coronal mass ejections has been identified in the SOHO Large Angle Spectroscopic Coronagraphs (LASCO) and the Ultraviolet Coronagraph Spectrometer (UVCS). UVCS data extends from the coronal base to 12 solar radii. The field of view for the LASCO coronagraphs, C2 and C3, is approximately 2.5 to 30 solar radii. Many coronal mass ejection (CME) measurements were made by UVCS, both intentional and fortuitous. However, often during these measurements, the UVCS slit was positioned below 2.5 solar radii resulting in the CME being obscured by the LASCO occulting disk at the UVCS slit height. In studies using only LASCO and UVCS data, the CME path must be extrapolated below the LASCO occulting disk. The Mauna Loa Solar Observatory's Mark-III and MK4, with field of views 1.122 to 2.44 solar radii and 1.14 to 2.86 solar radii respectively, provide white light measurements of the CME before it enters the LASCO field of view. From the MLSO data, we are able to better understand the acceleration of the CME in its early stages, and clearly identify the features observed by UVCS. We are also able to extract mass and electron density measurements. From the UVCS spectroscopic data, we are able to determine the coronal plasma parameters before, during, and after the ejection. Here we provide a progress report on our preliminary analysis of 16 events observed by both UVCS and MLSO. Future work will include calculations of plasma parameters including abundances, outflow velocities, rotation, etc.