X-Ray, Radio and SEP Observations of Relativistic Gamma-Ray Events
: Karl-Ludwig Klein, Kostas Tziotziou, Pietro Zucca, Eino Valtonen, Nicole Vilmer, Olga E. Malandraki, Clarisse Hamadache, Bernd Heber, Jürgen Kiener
: Olga E. Malandraki, Norma B. Crosby
: 2018
: Solar Particle Radiation Storms Forecasting and Analysis: The HESPERIA HORIZON 2020 Project and Beyond
: Astrophysics and Space Science Library
: 444
: 133
: 155
: 978-3-319-60050-5
: 978-3-319-60051-2
: 0067-0057
DOI: https://doi.org/10.1007/978-3-319-60051-2_8
: https://link.springer.com/chapter/10.1007/978-3-319-60051-2_8
: https://research.utu.fi/converis/portal/detail/Publication/36934483
The rather frequent occurrence, and sometimes long duration, of -
ray events at photon energies above 100 MeV challenges our understanding of
particle acceleration processes at the Sun. The emission is ascribed to pion-decay
photons due to protons with energies above 300 MeV.We study the X-ray and radio
emissions and the solar energetic particles (SEPs) in space for a set of 25 Fermi
-ray events. They are accompanied by strong SEP events, including, in most cases
where the parent activity is well-connected, protons above 300 MeV. Signatures of
energetic electron acceleration in the corona accompany the impulsive and early
post-impulsive -ray emission. -ray emission lasting several hours accompanies
in general the decay phase of long-lasting soft X-ray bursts and decametric-tokilometric
type II bursts. We discuss the impact of these results on the origin of
the -ray events.
