SH33B-2464
Longitudinal Properties of a Widespread Solar Energetic Particle Event on 2014 February 25: Evolution of the Parent CME and Associated Shock
Wednesday, 16 December 2015
Poster Hall (Moscone South)
David Lario1, Ryun Young Kwon2,3, Athanasios Papaioannou4, Nina Dresing5, Nour-Eddine Raouafi6, Raul Gomez-Herrero7, George C Ho3, Angelos Vourlidas3 and Pete Riley8, (1)Johns Hopkins University, Baltimore, MD, United States, (2)George Mason University Fairfax, School of Physics, Astronomy and Computational Sciences, Fairfax, VA, United States, (3)The Johns Hopkins University, Applied Physics Laboratory, Laurel, MD, United States, (4)National Observatory of Athens, Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, Athens, Greece, (5)University of Kiel, Kiel, Germany, (6)Applied Physics Laboratory Johns Hopkins, Laurel, MD, United States, (7)University of Alcala, Space Research Group, Physics and Mathematics Department, Alcala de Henares, Spain, (8)Predictive Science Inc., San Diego, CA, United States
Abstract:
We investigate the solar phenomena associated with the origin of the solar energetic particle (SEP) event observed on 2014 February 25 by a number of spacecraft distributed in the inner heliosphere over a broad range of heliolongitudes. These include a number of near-Earth spacecraft, the twin Solar TErrestrial RElations Observatory spacecraft, STEREO-A and STEREO-B, located at ~1 AU from the Sun 153 deg ahead and 160 deg behind Earth, respectively; the MErcury Surface Space ENvironment GEochemistry and Ranging (MESSENGER) mission (at 0.40 AU and 31 deg west of Earth), and the Juno spacecraft (at 2.11 AU and 48 deg east of Earth). Although the footpoints of the field lines nominally connecting the Sun with STEREO-A, STEREO-B and near-Earth spacecraft were quite distant one from each other, an intense Fe-rich SEP event with fast rising intensities was observed at all three locations. The extent of the Extreme UltraViolet (EUV) wave associated with the solar eruption generating the SEP event was very limited in longitude, but the white-light shock accompanying the associated coronal mass ejection (CME) extended over a broad range of longitudes. As the shock propagated into interplanetary space it extended over at least 190 deg in longitude when it arrived at ~1 AU. The release of the SEPs observed at different longitudes occurred when the shock associated with the CME was already high in the corona (>~2 solar radii above the solar surface). We argue that the expanding shock in the extended corona played a fundamental role in the injection of SEPs at different longitudes.
