Search Publications

Properties of Ground Level Enhancement Events and the Associated Solar Eruptions During Solar Cycle 23

Gopalswamy, N.; Yashiro, S.; Mäkelä, P. +3 more

Solar cycle 23 witnessed the most complete set of observations of coronal mass ejections (CMEs) associated with the Ground Level Enhancement (GLE) events. We present an overview of the observed properties of the GLEs and those of the two associated phenomena, viz., flares and CMEs, both being potential sources of particle acceleration. Although we…

What Are Special About Ground-Level Events?. Flares, CMEs, Active Regions and Magnetic Field Connection

Liu, Y.; Nitta, N. V.; Nightingale, R. W. +1 more

Ground level events (GLEs) occupy the high-energy end of gradual solar energetic particle (SEP) events. They are associated with coronal mass ejections (CMEs) and solar flares, but we still do not clearly understand the special conditions that produce these rare events. During Solar Cycle 23, a total of 16 GLEs were registered, by ground-based neu…

Observational Aspects of Particle Acceleration in Large Solar Flares

Krucker, Säm; Raymond, John C.; Lin, Robert P. +1 more

Solar flares efficiently accelerate electrons to several tens of MeV and ions to 10 GeV. The acceleration is usually thought to be associated with magnetic reconnection occurring high in the corona, though a shock produced by the Coronal Mass Ejection (CME) associated with a flare can also accelerate particles. Diagnostic information comes from em…