Alexandra Truebenbach (Wesleyan University)
The Ca II H and K and infrared triplet lines are important diagnostics of the solar atmosphere. To accurately infer solar atmospheric properties from their observed spectra, we need realistic atomic data. By using a new program that pulls atomic data from the NIST Atomic Spectra Database and TOPbase, we are able to create a variety of Ca II models. These models allow us to evaluate the accuracy of the data obtained from these databases and to determine which aspects of the Ca II model most affect the spectral lines. We found that the number of levels included in the Ca II model does not significantly contribute to the realism of the model but that the photoionization cross sections used can significantly affect the spectral lines. The cross sections provided in TOPbase are larger than those previously used to model Ca II and appear to generate a more physically accurate representation of the Ca II lines. With this knowledge, and the new program, we can efficiently analyze a greater number of atomic models in order to better understand the solar atmosphere.