On the Relationship of the Energy Spectrum Indexes of the 11-Year Variation of Galactic Cosmic Rays and the Interplanetary Magnetic Field Strength Fluctuations
Abstract
Data of neutron super monitors and interplanetary magnetic field (IMF) have been used to find a relationship between the temporal changes of galactic cosmic rays (GCR) isotropic intensity variations energy spectrum index γ (δ D/D(R) ∝ R-γ , where R is the rigidity of GCR particles) and the exponent ( of the power spectral density (PSD) of the IMF's strength fluctuations (PSD ∝ f-ν , where f is the frequency). INTRODUCTION. The 11-year variation of GCR is generally related with the similar variation of solar activity (SA) [1-5]. Up to present it is not well established which of parameters or group of parameters of SA and of the solar wind are responsible for the 11-year variation of GCR. To answer to this question it is necessary to estimate the separate contributions of each processes — convection, diffusion, drift and energy changes of GCR due to the interaction with the solar wind. However, all above mentioned processes are interconnected and an estimation of the roles of each separate processes contains some uncertainties. Regarding contributions of all above mentioned processes in the formation of the 11-year variation of GCR the special role is ascrib ed to the varying character of the diffusion from the minima to the maxima epochs of SA. It was noted [6-8] that the exponent γ of GCR isotropic intensity variations (δ D(R)/D (R) = AR-γ , where R is the GCR particle's rigidity and A is he power) could be considered as one of the important indices for the explanation of the 11-year variation of GCR for the energy more than 1 GeV.
- Publication:
-
International Cosmic Ray Conference
- Pub Date:
- July 2003
- Bibcode:
- 2003ICRC....7.3881A