Geomagnetic Storms Associated with Higher Peak  Value of IMFBz And Their Relation with Coronal Mass  Ejections And Solar Wind Parameters

P.L.Verma; Preetam Singh; Manoj Kumar Mishra; Arun Kumar; R.S.Gupta

Volume : II, Issue : II, November - 2012

Geomagnetic Storms Associated with Higher Peak Value of IMFBz And Their Relation with Coronal Mass Ejections And Solar Wind Parameters

P. L. Verma, Preetam Singh, Manoj Kumar Mishra, Arun Kumar, R. S. Gupta

Abstract :

An investigation of geomagnetic storms associated interplanetary magnetic field of higher peak values with observed between 1997 and 2010 with coronal mass ejections (CMEs) X–ray solar flares and solar wind plasma parameters was carried out. We found that majority 31(67.39%) of the geomagnetic storms are intense. Further it is found that 79.54% geomagnetic storms are associated with halo and partial halo coronal mass ejections. The association rates of halo and partial halo coronal mass ejections were found to be 85.71 and 14.28% respectively. It is also inferred that most of geomagnetic storms (79.82%) are associated with X–ray solar flares of different categories. The association rates of class X, class M, class C and class B X–ray solar flares are 13.33, 40.00, 28.88 and 20.00% respectively. Furthermore, it is concluded that these geomagnetic storms are closely related to disturbances in solar wind plasma parameters. Positive correlation with correlation coefficient 0.81and 0.79 has been found between magnitude of geomagnetic storms and maximum (peak) value and jump magnitude of average interplanetary magnetic field. The correlation coefficient of 0.83 and 0.60 between magnitude of geomagnetic storms and peak value and jump magnitude of associated jump in interplanetary magnetic field (JIMFBz ) events has been obtained. Positive correlation with correlation coefficient 0.56 and0.50 is also found between magnitude of geomagnetic storms and peak value and jump solar wind plasma velocity. The correlation coefficient of 0.45 and 0.36 between magnitude of geomagnetic storms and peak value and jump magnitude of solar wind plasma pressure is also obtained.