Observation of solar high energy gamma and X-ray emission and solar energetic particles

24th European Cosmic Ray Symposium

Struminsky, A.^1 ; Gan, W.^2

Space Research Institute, RAS, Profsoyuznaya st., 84/32, Moscow

117927, Russia^1

Purple Mountain Obervatory, CAS, 2 West Beijing Road, Nanjing

210008, China^2

关键词: Acceleration process;    Anticoincidence shield;    Energetic particle measurement;    High energy telescopes;    Large area telescopes;    Maximum temperature;    Solar energetic particles;    Solar proton events;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/632/1/012081/pdf
DOI  :  10.1088/1742-6596/632/1/012081

来源: IOP

【 摘 要 】

We considered 18 solar flares observed between June 2010 and July 2012, in which high energy >100 MeV γ-emission was registered by the Large Area Telescope (LAT) aboard FermiGRO. We examined for these γ-events soft X-ray observations by GOES, hard X-ray observations by the Anti-Coincidence Shield of the SPectrometer aboard INTEGRAL (ACS SPI) and the Gamma-Ray burst Monitor (GBM) aboard FermiGRO. Hard X-ray and π0-decay γ-ray emissions are used as tracers of electron and proton acceleration, respectively. Bursts of hard X-ray were observed by ACS SPI during impulsive phase of 13 events. Bursts of hard X- ray >100 keV were not found during time intervals, when prolonged hard y-emission was registered by LAT/FermiGRO. Those events showing prolonged high-energy gamma-ray emission not accompanied by >100 keV hard X-ray emission are interpreted as an indication of either different acceleration processes for protons and electrons or as the presence of a proton population accelerated during the impulsive phase of the flare and subsequently trapped by some magnetic structure. In-situ energetic particle measurements by GOES and STEREO (High Energy Telescope, HET) shows that five of these y-events were not accompanied by SEP events at 1 AU, even when multi-point measurements including STEREO are taken into account. Therefore accelerated protons are not always released into the heliosphere. A longer delay between the maximum temperature and the maximum emission measure characterises flares with prolonged high energy γ-emission and solar proton events.