This proposal will investigate the origins of solar energetic events by focusing on models of the trigger mechanisms, including those initiated by magnetic reconnection (e.g., tether cutting, breakout models) and by other mechanisms (e.g., the kink instability). Until now, only a few events have been studied in depth to investigate pre-event coronal signatures, and models of solar eruptions have only sparsely provided observables by which to test models. There are finally sufficient archived observational data and testable predictions from models that a rigorous statistical approach can be taken. The magnetic topology and pre-event coronal dynamics of solar energetic events will be characterized by parameterizations and moment analysis of coronal brightness maps and vector magnetograms, in order to avoid subjective data interpretation. This investigation will make use of data from the GOES, SoHO/LASCO, Yohkoh/SXT, and SoHO/EIT archives, as well as the Imaging Vector Magnetograph at the University of Hawaii's Mees Solar Observatory. The proposers' analysis will include control data sets for quiet times and regions, against which to test the null hypothesis. The variables derived from these data will be subjected to Discriminant Analysis, a statistical tool well suited for this approach. The power of Discriminant Analysis lies in its ability to differentiate between known populations, e.g., event-producing vs. event-quiet data points, in a multiple-variable parameter space. The assembled research team is well suited for the tasks of data acquisition, analysis, and interpretation in the context of the solar magnetic fields, plasma, and energetic events. Even if a specific model for the initiation of energetic events cannot be identified, it should be possible to put constraints on the processes involved.
The results of this study will aid in the definition and development of upcoming NSF-supported and collaborative projects, including the myriad ground-based and space-based efforts that include in their science goals the understanding of solar energetic events. By taking advantage of the archived data from long-running observational programs, this project will help focus the scientific approach and goals of future investigations.
