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Scattering mean free path of energetic protons in the Heliosphere

Balogh, A.; Erdos, Geza; Jota, J.

The effect of magnetic field fluctuations on charged particle propagation is investigated. Quasi-linear theory is used to deduce the diffusion coefficient of energetic particles from magnetic field data measured by Ulysses at high heliographic latitude. The λQLT scattering mean free path of 1 MeV protons is determined along one complete off-eclipt…

Solar Energetic Particle Events in the Rising Phase of Solar Cycle 23: Observations at 1 and 5 AU

Lario, David

We present energetic particle observations by the Ulysses and WIND spacecraft during the years 1997-1998. This period corresponds to the onset of the new solar cycle (23) when the increasing level of solar activity started to produce solar energetic proton (SEP) events. Several large and long-lasting SEP events were observed by both spacecraft dur…

Energy spectra of protons, deuterium, and helium nuclei during quiet solar activity periods in 1996-97

Valtonen, E.; Torsti, J.; Kecskemety, Karoly +4 more

A background reduction method based on pulse-height analysis (see accompanying paper by Valtonen et al.) is applied for the data of the ERNE and EPHIN energetic particle telescopes aboard SOHO. Energy spectra of protons, deuterons, 3He and 4He nuclei have been obtained during very low activity periods in 1996-97 in the energy range of 1.3 to 22 Me…

Corotating Interaction Regions in the Heliosphere:Workshop Report

Kunow, Horst

In June 1998 a workshop was held at the International Space Science Institute ISSI, Bern, Switzerland, on "Development and effects of Corotating Interaction Regions in the Heliosphere". The workshop was the last of a series of three and the results will be published shortly in Space Science Rewiews and in the Space Science Series of ISSI. The deve…

Propagation upstream from the shock of the High Latitude, Ulysses, CIR associated particle increases

Franz, M.; Blake, B.; Quenby, John +2 more

The first high solar latitude pass of the Ulysses spacecraft revealed the presence of MeV particle increases up to latitudes above 60 degrees, well outside the CIR belt but associated in time with the regular passage of these plasma interfaces at more equatorial latitudes. The particle increases have been explained variously as due to diffusion fr…

Gamma Ray Measurements of the 1991 November 15 Solar Flare

Ryan, J. M.; Bennett, K.; Rank, G. +6 more

The 1991 November 15 X1.5 flare is a well observed event. Comprehensive data from ground-based observatories and the Yohkoh, PVO, and Ulysses spacecrafts provide the basis for a contextual interpretation of gamma-ray spectra and light-curves from the Compton Observatory. In particular, spectral, spatial, and temporal data at several energies are n…