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Abstract The trajectories of coronal mass ejections (CMEs) are often seen to deviate substantially from a purely radial propagation direction. Such deviations occur predominantly in the corona and have been attributed to “channeling” or deflection of the eruptive flux by asymmetric ambient magnetic fields. Here, we investigate an additional mechanism that does not require any asymmetry of the preeruptive ambient field. Using magnetohydrodynamic numerical simulations, we show that the trajectories of CMEs through the solar corona can significantly deviate from the radial direction when propagation takes place in a unipolar radial field. We demonstrate that the deviation is most prominent below ∼15R⊙and can be attributed to an “effectiveI×Bforce” that arises from the intrusion of a magnetic flux rope with a net axial electric current into a unipolar background field. These results are important for predictions of CME trajectories in the context of space-weather forecasts, as well as for reaching a deeper understanding of the fundamental physics underlying CME interactions with the ambient fields in the extended solar corona.
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This content will become publicly available on April 13, 2027
Evolution of Coronal Mass Ejections in Different Data-driven Solar Wind Conditions
Abstract Numerical models of the solar wind and coronal mass ejections (CMEs) utilize photospheric magnetic field observations to prescribe the inner boundary conditions for the plasma solutions. These magnetic field data are available to the community through various observational instruments, prepared via different methodologies and/or flux transport models. The solar wind solution driven by these maps provides the ambient plasma environment into which CMEs travel. Interaction with the surrounding solar wind impacts CME evolution and propagation in the solar corona and inner heliosphere. In this work, we use different input magnetic field maps for the same time period to drive the global Alfvén Wave Solar atmosphere Model. We obtain the ambient solar wind conditions and compare the plasma properties and magnetic morphology in the corona domain to study the influence of the input maps. To understand how the resulting coronal solutions impact CMEs, we launch eruptions described by analytical flux ropes into these data-driven solutions and compare their evolution in the coronal domain (up to 24R⊙radially). The CMEs achieve varying speeds, deceleration rates, propagation directions, mass, and energies while coupling with the background solar wind. We quantify these differences to show that the different input driving maps can significantly impact the simulated CME propagation in the solar wind plasma. This also highlights the importance of understanding the uncertainties associated with data-driven modeling that become increasingly important in operational models and space weather prediction.
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- Award ID(s):
- 2323303
- PAR ID:
- 10689452
- Publisher / Repository:
- IOP Science
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 1001
- Issue:
- 2
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 144
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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