Energetic particle observations from the Ulysses COSPIN instruments obtained during the October-November 2003 events

Academic Article

Abstract

  • We report comprehensive observations of solar energetic particle intensities at energies from 0.3 to >100 MeV made by the suite of six Ulysses COSPIN energetic charged particle instruments on the Ulysses spacecraft during the period of intense solar activity in October/November 2003. We also discuss observations of particle anisotropies in selected energy ranges made by these instruments. Located near the orbit of Jupiter and only about 6° north of the heliographic equatorial plane, Ulysses provided important measurements for comparison with 1 AU observations and for assessing the nature of particle propagation in this period of isolated but intense solar activity in the declining phase of the solar activity cycle. The most significant conclusion is that the particle populations in the inner heliosphere were highly nonuniform throughout the events, strongly guided and confined by magnetic structures such as stream interfaces in the solar wind. This provides strong contrast to the nearly uniform intensities that were quickly established after large events near the peak of the solar cycle. Points of particular interest are (1) possible observation at 5.2 AU during onset of differential filling of flux tubes and confinement of high‐energy (>∼20 MeV) particles to flux tubes in the course of propagation from the source; (2) apparent exclusion of energetic particles from the interior of a large coronal mass ejection (CME); (3) possible triggered release of electrons from Jupiter by interaction with the same CME, and propagation of the electrons within the closed fields of the CME.
  • Authors

  • McKibben, RB
  • Anglin, JD
  • Connell, James
  • Dalla, S
  • Heber, B
  • Kunow, H
  • Lopate, C
  • Marsden, RG
  • Sanderson, TR
  • Zhang, M
  • Status

    Publication Date

  • September 27, 2005
  • Published In

    Digital Object Identifier (doi)

    Volume

  • 110
  • Issue

  • A9