【摘要】 分析了日本Nagoya宇宙线闪烁体望远镜30°,49°,64°倾角的东、西、南、北方向探测数据的变化特点,运用小波分析方法定性地探讨了磁暴前后宇宙线南北、东西各向异性的变化特征。研究发现,当发生大地磁暴时,地面宇宙线强度的各向异性特征将发生非常大的变化,这种变化一般在磁暴发生前10～20 h就开始出现。当描述这种各向异性特征的各向异性指数的小波系数变化达到一定阈值时,就可能有大地磁暴发生。更多还原

【Abstract】 Cosmic rays are energetic particles originating from outer space that impinge on Earth’s atmosphere.Almost 90%of all the incoming cosmic ray particles are protons,about 9%are helium nuclei and about 1%are electrons.The nuclei that make up cosmic rays are able to travel from their distant sources to the Earth because of the low density of matter in space.Nuclei interact strongly with other matter,so when the cosmic rays approach Earth they begin to collide with the nuclei of atmospheric gases.These collisions,in a process known as shower,result in the production of many pions and kaons,unstable mesons which quickly decay into muons.Muons are ionizing radiation,and may easily be detected by many types of particle detectors such as bubble chambers or scintillation detectors.Based on the muon measurement data of 30°,49°,64°of East,West,South,North components of cosmic ray from Nagoya station,the north-south and west-east anisotropy of cosmic ray just before geomagnetic disturbances and quiet days is analyzed by use of Haar wavelet.It was found that fluctuations of the anisotropy of cosmic ray before geomagnetic disturbances increased due to the approaching of CME because the shock front and strong IMF induced by CME and the coefficient of wavelet always increased monotonously more than 10 hours ahead the geomagnetic storm,which hopefully could be the premonitory properties of the eruption of severe geomagnetic storm.更多还原