Authors: Alessandro Liberatore (JPL/CALTECH), Paulett Liewer (JPL/CALTECH), Marco Velli (UCLA), Olga Panasenco (Adv.Helio), Angelos Vourlidas (JHU-APL), Carlos R. Braga (G.Mason Univ.), Daniele Telloni (INAF-OATo), Salvatore Mancuso (INAF-OATo)

This paper reports on a coronal mass ejections (CME) observed on 2022 March 25 associated with a well-defined global EUV wave observed by the Extreme Ultraviolet Imager (EUVI) on board the Solar Terrestrial Relations Observatory (STEREO-A/STA). The CME was visible to multiple spacecraft and observed by different remote sensing instruments on board Solar Orbiter (SolO/SO) during its first close perihelion (at about 0.32 AU). This work aims to perform a frame-by-frame analysis of the propagation of this event in relation to the evolution of the associated EUV wave. Through this analysis, it was possible to examine the capability of the main interpretations on the nature of the EUV waves to fit the observations and their interrelation with the CME propagation.

A kinematic analysis of both the EUV wave and CME propagation is performed via visual identification of the fronts thanks to the EUVI high-temporal cadence and the almost quadrature with SolO. Through the multi-spacecraft observations, it was also possible to perform a Graduated Cylindrical Shell (GCS) model obtaining the main geometrical features of the evolving CME. Finally, the analysis of the radio data and the overlay of the EUV wavefront on magnetic and Alfvén-velocity maps add information on the early phase of the EUV wave propagation and its evolution.

The clear observation of the decoupling moment between the EUV wave and the associate CME via imaging, kinematic study, radio analysis, and comparison with maps/models indicate that the observed EUV wave is best interpreted as a hybrid phenomenon that starts as a pseudo-wave driven by the lateral expansion of the CME and then propagates as a fast-mode magneto-hydrodynamic wave.