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Title: EUHFORIA modelling of the Sun-Earth chain of the magnetic cloud of 28 June 2013

Context.Predicting geomagnetic events starts with an understanding of the Sun-Earth chain phenomena in which (interplanetary) coronal mass ejections (CMEs) play an important role in bringing about intense geomagnetic storms. It is not always straightforward to determine the solar source of an interplanetary coronal mass ejection (ICME) detected at 1 au.

Aims.The aim of this study is to test by a magnetohydrodynamic (MHD) simulation the chain of a series of CME events detected from L1 back to the Sun in order to determine the relationship between remote and in situ CMEs.

Methods.We analysed both remote-sensing observations and in situ measurements of a well-defined magnetic cloud (MC) detected at L1 occurring on 28 June 2013. The MHD modelling is provided by the 3D MHD European Heliospheric FORecasting Information Asset (EUHFORIA) simulation model.

Results.After computing the background solar wind, we tested the trajectories of six CMEs occurring in a time window of five days before a well-defined MC at L1 that may act as the candidate of the MC. We modelled each CME using the cone model. The test involving all the CMEs indicated that the main driver of the well-defined, long-duration MC was a slow CME. For the corresponding MC, we retrieved the arrival time and the observed proton density.

Conclusions.EUHFORIA confirms the results obtained in the George Mason data catalogue concerning this chain of events. However, their proposed solar source of the CME is disputable. The slow CME at the origin of the MC could have its solar source in a small, emerging region at the border of a filament channel at latitude and longitude equal to +14 degrees.

 
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Award ID(s):
1954983
PAR ID:
10565697
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Astronomy & Astrophysics
Date Published:
Journal Name:
Astronomy & Astrophysics
Volume:
683
ISSN:
0004-6361
Page Range / eLocation ID:
A28
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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