EGU21-3291
https://doi.org/10.5194/egusphere-egu21-3291
EGU General Assembly 2021
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Constraining the CME parameters of the spheromak flux rope implemented in EUHFORIA

Eleanna Asvestari1, Jens Pomoell1, Emilia Kilpua1, Simon Good1, Theodosios Chatzistergos2, Manuela Temmer3, Erika Palmerio4,5, Stefaan Poedts6,7, and Jasmina Magdalenic6,8
Eleanna Asvestari et al.
  • 1University of Helsinki, Physics, Helsinki, Finland (eleanna.asvestari@helsinki.fi)
  • 2Max Planck Institute for Solar System Research, Goettingen, Germany
  • 3Institute of Physics, University of Graz, Graz, Austria
  • 4Space Sciences Laboratory, University of California-Berkeley, Berkeley, USA
  • 5CPAESS, University Corporation for Atmospheric Research, Boulder, USA
  • 6Centre for mathematical Plasma Astrophysics, KU Leuven, 3001 Leuven, Belgium
  • 7Institute of Physics, University of Maria Curie-Sklodowska, ul. Radziszewskiego 10, Lublin, Poland
  • 8Solar-Terrestrial Centre of Excellence – SIDC, Royal Observatory of Belgium, Brussels, Belgium

Coronal mass ejections (CMEs) are primary drivers of space weather phenomena. Modelling the evolution of the internal magnetic field configuration of CMEs as they propagate through the interplanetary space is an essential part of space weather forecasting. EUHFORIA (EUropean Heliospheric FORecasting Information Asset) is a data-driven, physics-based model, able to trace the evolution of CMEs and CME-driven shocks through realistic background solar wind conditions. It employs a spheromak-type magnetic flux rope that is initially force-free, providing it with the advantage of modelling CME as magnetised structures. For this work we assessed the spheromak CME model employed in EUHFORIA with a test CME case study. The selected CME eruption occurred on the 6th of January 2013 and was encountered by two spacecraft, Venus Express and STEREO--A, which were radially aligned at the time of the CME passage. Our focus was to constrain the input parameters, with particular interest in: (1) translating the angular widths of the graduated cylindrical shell (GCS) fitting to the spheromak radius, and (2) matching the observed magnetic field topology at the source region. We ran EUHFORIA with three different spheromak radii. The model predicts arrival times from half to a full day ahead of the one observed in situ. We conclude that the choice of spheromak radius affected the modelled magnetic field profiles, their amplitude, arrival times, and sheath region length.

How to cite: Asvestari, E., Pomoell, J., Kilpua, E., Good, S., Chatzistergos, T., Temmer, M., Palmerio, E., Poedts, S., and Magdalenic, J.: Constraining the CME parameters of the spheromak flux rope implemented in EUHFORIA, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-3291, https://doi.org/10.5194/egusphere-egu21-3291, 2021.