The reason for the widespread energetic storm particle event of 13 March 2023

¹ Department of Physics and Astronomy, University of Turku, Turku, Finland
² Center for mathematical Plasma Astrophysics, KU Leuven, Kortrijk/Leuven, Belgium
³ Predictive Science Inc., San Diego, CA, USA
⁴ European Space Astronomy Centre, European Space Agency, Villanueva de la Cañada, Madrid, Spain
⁵ Universidad de Alcalá, Space Research Group (SRG-UAH), Alcalá de Henares, Madrid, Spain
⁶ Institut de Recherche en Astrophysique et Planétologie (IRAP), CNRS, Université de Toulouse III-Paul Sabatier, Toulouse, France
⁷ Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing (IAASARS), National Observatory of Athens, Penteli, Greece
⁸ Faculty of Science, University of Helsinki, Helsinki, Finland
⁹ Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD, USA
¹⁰ California Institute of Technology, Pasadena, CA, USA
¹¹ Space Sciences Laboratory, University of California–Berkeley, Berkeley, CA, USA
¹² The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
¹³ Leibniz-Institut für Astrophysik Potsdam (AIP), Potsdam, Germany
¹⁴ School of Physics and Astronomy, University of Leicester, Leicester, UK
¹⁵ Southwest Research Institute, Boulder, CO, USA
¹⁶ Space Research Center of Polish Academy of Sciences, Warsaw, Poland
¹⁷ Institute of Radio Astronomy of National Academy of Sciences of Ukraine, Kharkiv, Ukraine
¹⁸ Department of Physics, The Catholic University of America, Washington, DC, USA
¹⁹ Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, CO, USA

^⋆ Corresponding author; nina.dresing@utu.fi

Received: 23 December 2024
Accepted: 14 February 2025

Abstract

Context. On 13 March 2023, when the Parker Solar Probe spacecraft (S/C) was situated on the far side of the Sun as seen from Earth, a large solar eruption took place, which created a strong solar energetic particle (SEP) event observed by multiple S/C all around the Sun. The energetic event was observed at six well-separated locations in the heliosphere, provided by the Parker Solar Probe, Solar Orbiter, BepiColombo, STEREO A, near-Earth S/C, and MAVEN at Mars. Clear signatures of an in situ shock crossing and a related energetic storm particle (ESP) event were observed at all inner-heliospheric S/C, suggesting that the interplanetary coronal mass ejection (CME)-driven shock extended all around the Sun. However, the solar event was accompanied by a series of pre-event CMEs.

Aims. We aim to characterize this extreme widespread SEP event and to provide an explanation for the unusual observation of a circumsolar interplanetary shock and a corresponding circumsolar ESP event.

Methods. We analyzed data from seven space missions, namely Parker Solar Probe, Solar Orbiter, BepiColombo, STEREO A, SOHO, Wind, and MAVEN, to characterize the solar eruption at the Sun, the energetic particle event, and the interplanetary context at each observer location as well as the magnetic connectivity of each observer to the Sun. We then employed magnetohydrodynamic simulations of the solar wind in which we injected various CMEs that were launched before as well as contemporaneously with the solar eruption under study. In particular, we tested two different scenarios that could have produced the observed global ESP event: (1) a single circumsolar blast-wave-like shock launched by the associated solar eruption, and (2) the combination of multiple CMEs driving shocks into different directions.

Results. By comparing the simulations of the two scenarios with observations, we find that both settings are able to explain the observations. However, the blast-wave scenario performs slightly better in terms of the predicted shock arrival times at the various observers.

Conclusions. Our work demonstrates that a circumsolar ESP event, driven by a single solar eruption into the inner heliosphere, is a realistic scenario.