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Title: COMPARATIVE MORPHOLOGY OF SOLAR RELATIVISTIC PARTICLE EVENTS

Time profiles of the 0.25–10 MeV electrons and the ∼(0.1–1) GeV nucleon{sup −1} protons and helium associated with two solar coronal mass ejections (CMEs) are analyzed with a newly formulated method based on modeling of the particle transport in the interplanetary medium. With the modeling, we fit the observed angular distribution of solar particles and infer, for a particular particle instrument and magnetic field orientation, the time delay of the particle registration at 1 AU in respect to the solar source. Then, after the time offset removal, intensity re-normalization and background equalization, the time–intensity profiles of high-energy protons, helium and electrons in different energy channels are superposed and compared. The comparison reveals episodes of remarkable coincidence of different profiles, as well as episodes of essentially different behavior. It implies at least three sources of solar high-energy particles operating in a single event. The first, short-duration source emits electrons next to the flare's impulsive phase and CME liftoff. The second source gradually rises and continues for more than an hour, emitting electrons and lower energy protons, which is consistent with shock acceleration on open magnetic field lines extending to solar wind. An another, third source is the main source of relativisticmore » ions in space. It is retarded in respect to the flare's impulsive phase and may be associated with a structure encountered by the shock within a few solar radii from the Sun.« less
Authors:
;  [1] ;  [2] ;  [3] ;  [4]
  1. Sodankylä Geophysical Observatory (Oulu Unit), P.O.B. 3000, University of Oulu, FI-90014 Oulu (Finland)
  2. Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität, D-24118 Kiel (Germany)
  3. Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland)
  4. Space Science Center, Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH 03824 (United States)
Publication Date:
OSTI Identifier:
22518886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 811; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANGULAR DISTRIBUTION; COMPARATIVE EVALUATIONS; GEV RANGE; HELIUM; MAGNETIC FIELDS; MEV RANGE; ORIENTATION; RELATIVISTIC RANGE; SHOCK WAVES; SOLAR ELECTRONS; SOLAR PROTONS; SOLAR WIND; SPACE; SUN