A study of the Forbush decrease event of September 11, 2005 with GRAND

TL;DR

This study uses the GRAND detector to analyze the Forbush decrease of September 11, 2005, examining muon count reductions, directional anisotropies, and comparing results with other cosmic ray monitors.

Contribution

It provides new insights into ground-level muon variations and anisotropies during a geomagnetic storm using GRAND's angular resolution.

Findings

Muon count decrease observed during the event

Directional anisotropies identified prior to the storm

Comparison with other cosmic ray data shows consistency

Abstract

Project GRAND, a proportional wire chamber array, is used to examine the decreased counting rate of ground level muons during the Forbush decrease event of September 11, 2005. Data are presented and compared to that of other cosmic ray monitors. A directional study of the Forbush decrease was undertaken and precursor anisotropies to this geomagnetic storm were studied utilizing GRAND's angular resolution.