2019/04/07 by Bing-Bing Wang, Bingbing Wang, Xiao-Jun Bi +6 · 20 citations
Physics and Astronomy · #Astro and Planetary Science #Astronomy #Astrophysics #Computational physics #Coronal mass ejection #Cosmic ray #Diffusion #Heliosphere #Heliospheric current sheet #Interplanetary magnetic field #Interplanetary medium #Interplanetary spaceflight #Modulation (music) #Nuclear physics #Physics #Plasma #Power law #Proton #Solar and Space Plasma Dynamics #Solar cycle #Solar maximum #Solar minimum #Solar wind #Spectral line #Stellar, planetary, and galactic studies #Thermodynamics #astro-ph.HE #physics.space-ph
paper · pdf · doi:10.1103/physrevd.100.063006
published in Physical review. D/Physical review. D. 100(6) (American Physical Society) · 23 pages,12 figures
arxiv created 2019/04/07 · openalex publication_date 2019/09/16 · arxiv updated 2019/09/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the time-dependent modulation effect and derive the local interstellar spectra (LIS) for the cosmic ray (CR) proton, helium, boron, and carbon. A two-dimensional modulation model including the variation of the interplanetary environment with time is adopted to describe the modulation process. The propagation equation of CRs in the heliosphere is numerically solved by the package Solarprop. We derive the LIS by fitting the latest results of several experiments, including Voyager 1, PAMELA, BESS-POLARII, and ACE, during low solar activity periods. We further study the modulation in the polarity reversal periods with the PAMELA proton data. We find that the rigidity dependence of the diffusion coefficient is critical to explain the modulation effect during reversal periods. Our results also indicate a power law relation between the diffusion coefficient and the magnitude of the heliospheric magnetic field at the Earth.