SH43A-4188:
The Solar Energetic Particle Event on 2013 April 11: An Investigation of the Solar Origin of its Longitudinal Widespread
Thursday, 18 December 2014
David Lario1, Nour-Eddine Raouafi2, Ryun Young Kwon3, Jie Zhang3, Raul Gomez-Herrero4, Nina Dresing5 and Pete Riley6, (1)The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, United States, (2)Applied Physics Laboratory Johns Hopkins, Laurel, MD, United States, (3)George Mason University Fairfax, School of Physics, Astronomy and Computational Sciences, Fairfax, VA, United States, (4)University of Alcala, Alcala de Henarez, Spain, (5)University of Kiel, Kiel, Germany, (6)Predictive Science Inc., San Diego, CA, United States
Abstract:
We report on the solar phenomena associated with the longitudinal extent of the solar energetic particle (SEP) event observed on 2013 April 11. SEPs were observed over a wide range of heliolongitudes by STEREO and near-Earth spacecraft. We use EUV and white-light coronagraph observations from SDO, SOHO, and STEREO to analyze the angular extent of the EUV and CME-driven shock waves associated with the SEP event. We compare the estimated release time of SEPs observed at each spacecraft with that of the arrival of the CME-associated waves at the footpoints of the magnetic field lines connecting each spacecraft to the solar surface. Whereas the arrival of the EUV wave and CME-driven shock at the footpoint of STEREO-B is consistent, within uncertainties, with the release time of the observed particles, the EUV wave never reached the footpoint of magnetic field lines connecting near-Earth spacecraft to the solar surface even though an intense SEP event was observed there. Modeling of the propagation of the CME-driven shock wave at high coronal altitudes shows that the latter was most likely the source of the particles observed near Earth. The present analysis shows that the angular extent of the EUV wave on the solar surface does not agree with the longitudinal extent of the SEP event in the heliosphere. Hence EUV waves cannot be used consistently as a proxy for the solar phenomena that accelerates and injects energetic particles over broad ranges of longitudes. Partly supported by NASA under grant NNX11A083G.
