Title: Coronal/Interplanetary Disturbances Relating to Strong Solar Proton Events
Author: Takashi Watanabe
Affil: Department of Environmental Sciences, Ibaraki University
Email: watanabe@env.sci.ibaraki.ac.jp
Authors: Masayoshi Kojima, and Munetoshi Tokumaru
Affils: Solar-Terrestrial Environment Laboratory, Nagoya University
Abstract: Strong proton events and GLEs were frequently observed when energetic solar flares took place near the central meridian of the Sun (even in the eastern hemisphere) , far from the ""favorite" longitude (about 60 W) for solar-particle propagation to the Earth along the line of force of the interplanetary magnetic field. IPS and white-light coronal observations are principal data sources of this study. IPS observations will be useful to find the presence of a high-speed interplanetary disturbance at the favorite longitude. For these events, high-speed (>800 km/sec) disturbances with broad extents in the heliocentric longitude were observed in the western hemisphere of interplanetary space. The energy spectra of these events were very "hard", suggesting the quasi-parallel condition of the shock normal. On the other hand, non-GLE energetic proton events with soft energy spectra, the speed of a related interplanetary disturbance at the favorite longitude was small, although the shock speed near the Sun-Earth line was high, suggesting a quasi-perpendicular condition of the shock normal.