Principal Component Analysis of Ground Level Enhancement of Cosmic Ray Events

We applied principal component analysis (PCA) to the study of five ground level enhancement (GLE) cosmic ray (CR) events. The nature multivariate data involved makes PCA a useful tool for this study. A subroutine program written and implemented in R software environment generated interesting components. Analysis results shows that method can distinguish between neutron monitors (NMs) observed Forbush decrease (FD) from those GLE at same time. equally assigned NMs with identical signal counts correlation factor (r) close r values have resemblance their CR counts. further indicate while time peak may not r, most had also peak. Analyzing second components yielded information on differences having opposite but or r. tendency being latitude.