Abstract:
In this work we have studied flare related geomagnetic storms of magnitude ≤-90nT during the period of 1997-2012 and analyzed with coronal mass ejections, X-ray solar flares and disturbances in solar wind plasma parameter. We have found total number of flare related geomagnetic storms are 87. Out of 87 geomagnetic storms 67(77.00%) geomagnetic storms are found to be associated with coronal mass ejections (CMEs). Further we observed that 68.66% and 31.34% geomagnetic storms are associated with halo and partial halo CMEs. Statistically there is positive correlation between magnitude of flare related geomagnetic storms and speed of associated CMEs with correlation coefficient 0.28. All the geomagnetic storms have been identified as being associated with X-ray solar flares and 42(48.27 %) flare related geomagnetic storms have been found to be associated with radio bursts of different categories type-II and type-IV. Further we have analyzed those jumps in solar wind plasma density (JSWD) which are associated with flare related geomagnetic storms and see the statistical behavior with CMEs. Positive co-relation has been found between speed of CMEs and peak value of associated JSWD events with coefficient 0.23. Again there is a Positive co-relation with correlation coefficient 0.28 has been found between magnitudes of JSWD events and speed of associated CMEs.
Keywords: – Coronal mass ejections, Solar flare, Geomagnetic storms, Radio bursts.
Shiva Soni1*, Preetam Singh Gour2