Forward Modeling of Coronal Mass Ejection Flux Ropes in the Inner Heliosphere with 3DCORE.

Area of Science:

• Space Physics
• Heliophysics
• Geomagnetism

Background:

• Forecasting geomagnetic effects of solar storms (CMEs) is limited by predicting CME magnetic field configuration and single spacecraft observations.
• CME magnetic flux ropes with southward magnetic fields can continuously energize Earth's magnetosphere.

Purpose of the Study:

• To demonstrate a novel approach for predicting the southward magnetic field (Bz) within a CME flux rope.
• To improve space weather forecasting and heliospheric data interpretation.

Main Methods:

• Developed the Three-Dimensional Coronal ROpe Ejection (3DCORE) semiempirical model for CME flux rope magnetic fields.
• Combined 3DCORE with solar observations and in situ magnetic field data (MESSENGER spacecraft, July 9-13, 2013).
• Included interplanetary propagation, 3D flux rope evolution, synthetic spacecraft observations, and geomagnetic activity prediction.

Main Results:

• Observed a 30° counterclockwise rotation and 20° deflection of the erupting CME flux rope in the corona.
• The model's predicted Dst index reasonably matched the observed Dst minimum and its temporal evolution.
• Results showed high sensitivity to the CME axis orientation.

Conclusions:

• The 3DCORE model represents a significant advancement in predicting CME magnetic fields and their geomagnetic impact.
• The prototype method shows potential for real-time space weather forecasting.
• Further refinement is needed, addressing assumptions and limitations, particularly CME axis orientation sensitivity.