Drift Effects on the Galactic Cosmic Ray Modulation

摘要: Cosmic ray (CR) modulation is driven by both solar activity and drift effects in the heliosphere, although their role only qualitatively understood as it difficult to connect CR variations sources. In order address this problem, Empirical Mode Decomposition technique has been applied intensity, recorded three neutron monitors at different rigidities (Climax, Rome, Huancayo-Haleakala (HH)), sunspot area, a proxy for activity, heliospheric magnetic field magnitude, directly related propagation, tilt angle (TA) of current sheet (HCS), which characterizes on CRs. A prominent periodicity ~six years detected all analyzed data sets found be highly correlated with changes HCS inclination same timescale. addition, variation responsible main features during periods low such flat (peaked) maximum even (odd) cycles. The contribution global Galactic estimated between 30% 35%, depending particle energy. Nevertheless, importance generally reduced nearing maximum. Finally, threshold values ~40°, ~45°, >55° have derived TA, critical Climax, HH rigidity thresholds, respectively.