In this work, we report a statistical study for the relationship between coronal mass ejections (CMEs) of velocity >500 km/s and sunspot number (SSN) that were registered during the period 1996-2015. For this duration by the glance at the data that in the years 2008 and 2009 didn’t recorded even single CMEs over the speed of 500 km/sec. On the other side sunspots have shown regularity even in the declining phase of solar cycle. Furthermore we have calculate the correlation between sun spot number (SSN) and CMEs for every year and found that strong positive correlation for the 2001,2005,2007 years, moderate correlation in 2011 and weak positive correlation in 1996,1997,1999,2006 and strong negative correlation in the 2015, with no correlation some times. Test results of the annual correlation between SSN and CMEs is 0.79 and can be represented by a linear regression equation. From this study we concluded that sun spot number and CMEs are well correlated in most of the yearly compiled data for this time span.
Keywords: – Sun spot number, coronal mass ejections, solar cycle.
Preetam Singh Gour, Hemant Joshi, Shiva Soni