Authors: Lulu Zhao (University of Michigan), Tamas Gombosi (University of Michigan, the CLEAR Team

The CLEAR space weather center of excellence participated in the Space Weather Prediction Testbed (SWPT) exercise held at SWPC in the first week of May, 2025. This exercise was planned in support of Human Space Exploration and the Artemis-II Mission. Two historical solar energetic particle (SEP) events were selected to evaluate the performance of various SEP prediction models, with a particular focus on the onset and peak phases of each event. The SOlar wind with FIeld lines and Energetic particles (SOFIE) model was run onsite under real-time conditions using an incoming data stream to mirror operational usage.

SOFIE is built in the space weather modeling frame developat at the University of Michigan. In SOFIE, the solar wind in the solar corona and inner heliosphere is modeled by the AWSoM model, the generation of CME is modeled by the EEGGL model, and the acceleration and transport of energetic particles are modeled by MFLAMPA. In operation, the background solar wind will be prepared daily, enabling the initialization of SOFIE whenever a CME is detected. During the testbed exercise, the EEGGL model was launched to calculate the parameters for the spheromak flux rope inserted into the source region of CME once the CME was detected by the coronagraph and the speed of the CME could be determined (requiring 4 image frames). Then the acceleration of energetic particles in the CME driven shock and the subsequent transport process is solved by MFLAMPA. The flux of energetic particles at energies of >10 MeV and >100 MeV were predicted well ahead of time. SOFIE successfully predicted flux levels of the next four days within the first four hours of the event. The performance of SOFIE, along with associated uncertainties and limitations, will be discussed in detail.