A novel metric for coronal MHD models

In the interest of quantitatively assessing the capabilities of coronal MHD models, we have developed a metric that compares the structures of the white light corona observed with SOHO LASCO C2 to model predictions. The MAS model is compared to C2 observations from two Carrington rotations during solar cycle 23, CRl913 and CR 1984, which were near the minimum and maximum of solar activity, respectively, for three radial heights,2.5 R_⊙, 3.0 R _⊙, and 4.5 R_⊙. In addition to simulated polarization brightness images, we create a synthetic image based on the field topology along the line of sight in the model. This open-closed brightness is also compared to LASCO C2 after renormalization. In general, the model's magnetic structure is a closer match to observed coronal structures than the model's density structure. This is expected from the simplified energy equations used in current global corona MHD models.