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arXiv · 2409.03281

Extended Drag-Based Model for better predicting the evolution of Coronal Mass Ejections

Mattia Rossi·Sabrina Guastavino·Michele Piana·Anna Maria Massone
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Abstract

The solar wind drag-based model is a widely used framework for predicting the propagation of Coronal Mass Ejections (CMEs) through interplanetary space. This model primarily considers the aerodynamic drag exerted by the solar wind on CMEs. However, factors like magnetic forces, pressure gradients, and the internal dynamics within CMEs justify the need of introducing an additional small-scale acceleration term in the game. Indeed, by accounting for this extra acceleration, the extended drag-based model is shown to offer improved accuracy in describing the evolution of CMEs through the heliosphere and, in turn, in forecasting CME trajectories and arrival times at Earth. This enhancement is crucial for better predicting Space Weather events and mitigating their potential impacts on space-based and terrestrial technologies.

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Mattia Rossi, Sabrina Guastavino, Michele Piana, Anna Maria Massone. 2024-09-05. Extended Drag-Based Model for better predicting the evolution of Coronal Mass Ejections. https://doi.org/10.1051/0004-6361%2F202452288

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