Modeling CME encounters at Parker Solar Probe with OSPREI: Dependence on photospheric and coronal conditions

Context. Coronal mass ejections (CMEs) are eruptions of plasma from the Sun that travel through interplanetary space and may encounter Earth. CMEs often enclose a magnetic flux rope (MFR), the orientation of which largely determines the CMEs' geoeffectiveness. Current operational CME models do not model MFRs, but a number of research ones do, including the Open Solar Physics Rapid Ensemble Information (OSPREI) model.Aims. We report the sensitivity of OSPREI to a range of user-selected photospheric and coronal conditions.Methods. We modeled four separate CMEs observed in situ by Parker Solar Probe (PSP). We varied the input photospheric conditions using four input magnetograms (HMI Synchronic, HMI Synoptic, GONG Synoptic Zero-Point Corrected, and GONG ADAPT). To vary the coronal field reconstruction, we employed the Potential Field Source Surface (PFSS) model and varied its source-surface height in the range 1.5-3.0 R-circle dot with 0.1 R-circle dot increments.Results. We find that both the input magnetogram and PFSS source surface often affect the evolution of the CME as it propagates through the Sun's corona into interplanetary space, and therefore the accuracy of the MFR prediction compared to in situ data at PSP. There is no obvious best combination of input magnetogram and PFSS source surface height.Conclusions. The OSPREI model is moderately sensitive to the input photospheric and coronal conditions. Based on where the source region of the CME is located on the Sun, there may be best practices when selecting an input magnetogram to use.

Automated summary

The sensitivity of the OSPREI model to different solar magnetic and coronal conditions is reported. It is found that the solar magnetic and coronal conditions affect the evolution of CMEs as they propagate through the Sun's corona and into interplanetary space, as well as the accuracy of MFR prediction. Best practices may exist when selecting an input magnetogram based on the source region of the CME on the Sun.