Particle bursts (PBs), the phenomena characterized by short-term increases of particle counting rates (CRs), were observed by space-borne radiation belt particle detectors. With the electron CR data obtained by Na...Particle bursts (PBs), the phenomena characterized by short-term increases of particle counting rates (CRs), were observed by space-borne radiation belt particle detectors. With the electron CR data obtained by National Oceanic and Atmospheric Ad- ministration (NOAA)-18 satellite, the occurrence of PBs in the inner belt (I〈~L〈2 and B〉20.5 gT) were derived for years 2006-2011. The monthly occurrence number of PBs exhibits a strong maximum in northern summer (May-August). In associ- ation with global lightning data, the seasonal occurrence of PBs is found to be consistent with the lightning activity, especially if only lightning flashes at latitudes 〉20~ are taken into account. The positive correlation between PBs and mid-latitude light- ning discharges indicates the role of lightning-induced whistler waves, and is consistent with the expected pitch-angle scatter- ing by wave-particle interactions. The contribution of lightning is so significant that it forms a non-negligible seasonal back- ground of PBs. If one connects PBs to seismoelectromagnetic emissions (SEME) in attempt to find the earthquake precursor, the lightning background needs to be considered with great care.展开更多
基金supported by the National Basic Research Program of China("973" Project)(Grant Nos.2012CB957801,2011CB811405)the National Natural Science Foundation of China(Grant Nos.41274155,40904036)+1 种基金the Public Science and Technology Research Funds Projects of Ocean,State Oceanic Administration of China(Grant No.201005017)the Specialized Research Fund for State Key Laboratories
文摘Particle bursts (PBs), the phenomena characterized by short-term increases of particle counting rates (CRs), were observed by space-borne radiation belt particle detectors. With the electron CR data obtained by National Oceanic and Atmospheric Ad- ministration (NOAA)-18 satellite, the occurrence of PBs in the inner belt (I〈~L〈2 and B〉20.5 gT) were derived for years 2006-2011. The monthly occurrence number of PBs exhibits a strong maximum in northern summer (May-August). In associ- ation with global lightning data, the seasonal occurrence of PBs is found to be consistent with the lightning activity, especially if only lightning flashes at latitudes 〉20~ are taken into account. The positive correlation between PBs and mid-latitude light- ning discharges indicates the role of lightning-induced whistler waves, and is consistent with the expected pitch-angle scatter- ing by wave-particle interactions. The contribution of lightning is so significant that it forms a non-negligible seasonal back- ground of PBs. If one connects PBs to seismoelectromagnetic emissions (SEME) in attempt to find the earthquake precursor, the lightning background needs to be considered with great care.