The Bulletin of The Korean Astronomical Society (천문학회보)
- Volume 35 Issue 1
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- Pages.34.1-34.1
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- 2010
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- 1226-2692(pISSN)
Identification of backside solar proton events
- Park, Jin-Hye (Kyung Hee University, School of space research) ;
- Moon, Yong-Jae (Kyung Hee University, School of space research) ;
- Lee, Dong-Hun (Kyung Hee University, School of space research)
- Published : 2010.04.06
Abstract
Solar proton events, whose fluxes are larger than 10 particles cm-2 sec-1 ster-1 for >10 MeV protons, have been observed since 1976. NOAA proton event list from 1997 to 2006 shows that most of the events are related to both flares and CMEs but a few fraction of events (5/93) are only related with CMEs. In this study, we carefully identified the sources of these events. For this, we used LASCO CME catalog and SOHO MDI data. First, we examined the directions of CMEs related with the events and the CMEs are found to eject from the western hemisphere. Second, we searched a major active region in the front solar disk for several days before the proton events occurred by taking into account two facts: (1) The location of the active region is consistent with the position angle of a given CME and (2) there were several flares in the active region or the active region is the largest among several candidates. As a result, we were able to determine active regions which are likely to produce proton events without ambiguity as well as their longitudes at the time of proton events by considering solar rotation rate,
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