Authors: Elizabeth Wraback (University of Michigan), Enrico Landi (University of Michigan), Ward Manchester (University of Michigan)

The early evolution of coronal mass ejections (CME) is a relatively unknown period due to the difficulty of observing it. Coronagraphs block observations within ~1.5 Rs, while on-disk observations from EUV and X-ray imagers are hindered by the brighter background emission, making limb observations the best way to study CME plasma properties. High-resolution EUV spectroscopy of the corona provides the best diagnostic tool since it can directly observe the dynamics and thermodynamics of CME plasma close to the Sun, even if the small field of view is an obstacle to CME detection at the limb. The Cartwheel CME’s lift-off was observed on 9 April 2008 by a series of remote sensing observations performed by instruments aboard Hinode, SOHO, and STEREO-A. In particular, Hinode/EIS captured its full range of high-resolution EUV spectra of the initial acceleration period. This work focuses on the physical properties of the CME plasma during its early evolution, as observed by EIS at 1.1 Rs. Unique to this work, simulations of the Cartwheel CME with the Alfvén Wave Solar Model (AWSoM), including EUV spectral line synthesis and self-consistent non-equilibrium charge state calculations, are being performed to provide insight into the plasma structure and dynamics of the Cartwheel CME’s early evolution.