The long period of ³He-rich solar energetic particles measured by Solar Orbiter 2020 November 17-23

R. Bučík , G. M. Mason , R. Gómez-Herrero , D. Lario , L. Balmaceda , N. V. Nitta , V. Krupař , N. Dresing , G. C. Ho , R. C. Allen , F. Carcaboso , J. Rodríguez-Pacheco , F. Schuller , A. Warmuth , R. F. Wimmer-Schweingruber , J. L. Freiherr von Forstner , G. B. Andrews , L. Berger , I. Cernuda , F. Espinosa Lara , W. J. Lees , C. Martín , D. Pacheco , M. Prieto , S. Sánchez-Prieto , C. E. Schlemm , H. Seifert , K. Tyagi , M. Maksimovic (1) , A. Vecchio (1) , A. Kollhoff , P. Kühl , Z. G. Xu , S. Eldrum

1 LESIA (UMR_8109) - Laboratoire d'études spatiales et d'instrumentation en astrophysique

We report observations of a relatively long period of ³He-rich solar energetic particles (SEPs) measured by Solar Orbiter. The period consists of several well-resolved ion injections. The high-resolution STEREO-A imaging observations reveal that the injections coincide with extreme ultraviolet jets and brightenings near the east limb, not far from the nominal magnetic connection of Solar Orbiter. The jets originated in two adjacent, large, and complex active regions, as observed by the Solar Dynamics Observatory when the regions rotated into the Earth's view. It appears that the sustained ion injections were related to the complex configuration of the sunspot group and the long period of ³He-rich SEPs to the longitudinal extent covered by the group during the analyzed time period.

Keywords: acceleration of particles; Sun: abundances; Sun: flares; Sun: particle emission; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics

Domains: Sciences of the Universe [physics]; Sciences of the Universe [physics]; Astrophysics [astro-ph]

R. Bučík, G. M. Mason, R. Gómez-Herrero, D. Lario, L. Balmaceda, et al.. The long period of ³He-rich solar energetic particles measured by Solar Orbiter 2020 November 17-23. Astronomy and Astrophysics - A&A, 2021, 656, ⟨10.1051/0004-6361/202141009⟩. ⟨insu-03713742⟩