Analysis of Ground Level Events, Solar Flares, and Forbush Decreases

The sun, while normally not a source for high energy cosmic rays, does still at times produce energetic events such as solar flares or coronal mass ejections. These events, as has been shown by ground level based detectors, have the capability to accelerate protons to energies on the order of 1~GeV. Ground level muon detector stations are capable of detecting secondary muons from energies greater than 20~GeV. However such detections are extremely rare. Project GRAND, an array of ground level secondary muon stations, with an angular resolution of 0.26 degrees on a projected plane and a counting rate of 1800 muons/s, is an excellent tool for detecting ground level events associated with solar phenomena. The ground level muon counting rate for two solar X-ray flares (April 15, 2001 and January 20, 2005) are examined in detail for evidence of an enhancement immediately following the X-ray flares. The ground level counting rate during the October 29, 2003 Forbush decrease is examined and a simple model for the propagation of ejecta from a coronal mass ejections is presented.