Analysis of Ground Level Enhancement Events of 1989 September 29; 2001 April 15 and 2005 January 20

Abstract We present the results of analyses ground level enhancements (GLEs) cosmic ray (CR) events on 1989 September 29; 2001 April 15 and 2005 January 20. This involves examination hourly raw CR counts an array neutron monitors (NMs) spread across different geographical latitudes longitudes. Using awk script computer codes implemented in R software, pressure corrected data plots NMs were grouped into low-, mid- high-latitudes. The show both similarities differences structural patterns GLE signals. In attempt to explain why count during decay phase GLEs is always higher than before peak, we interpreted all prior peak as coming from direct solar neutrons those including secondary generated by interactions primary CRs with atoms molecules atmosphere. identified that detected these found they are close longitude. Previous authors seemingly two species impulsive gradual events. Although there a number unexplained manifestations signals, some suggest geomagnetic rigidity effectively determines intensity at low- mid-latitudes. Its impact apparently insignificant high-latitude regions. Nevertheless, presented should be validated making any firm statements. Principally, contributions ever-present intractable diurnal anisotropies signals accounted for future work.