Investigation of the Relation between Space-Weather Parameters and Forbush Decreases Automatically Selected from Moscow and Apatity Cosmic Ray Stations during Solar Cycle 23

TL;DR

This study analyzes the relationship between space-weather parameters and cosmic ray intensity decreases during solar cycle 23, using automated detection of Forbush decreases from two neutron monitor stations, revealing significant correlations.

Contribution

It introduces an automated method for detecting Forbush decreases and analyzes their relation to space-weather parameters across two stations during solar cycle 23.

Findings

Significant correlation between space-weather disturbances and cosmic ray decreases.

229 simultaneous Forbush decreases detected at both stations.

Large FDs show stronger association with space-weather parameters.

Abstract

We present the results of an investigation of the relation between space-weather parameters and cosmic ray (CR) intensity modulation using algorithm-selected Forbush decreases (FDs) from Moscow (MOSC) and Apatity (APTY) neutron monitor (NM) stations during solar cycle 23. Our FD location program detected 408 and 383 FDs from MOSC and APTY NM stations respectively. A coincident computer code employed in this work, detected 229 FDs that were observed at the same universal Time (UT) at the two stations. Out of the 229 simultaneous FDs, we formed a subset of 139 large FDs(\%) $\leq-4$ at Moscow station. We peformed a two dimensional regression analysis between the FD magnitudes and the space-weather data on the two samples. We find that there were significant space-weather disturbances at the time of the CR flux depressions. The correlation between the space-weather parameters and galactic cosmic ray (GCR) intensity decreases at the two NM stations are statistically significant. The implications of the present space-weather data on cosmic ray (CR) intensity depressions are highlighted.