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Full-Text Articles in Physical Sciences and Mathematics
Heliospheric Influence On The Anisotropy Of Tev Cosmic Rays, Ming Zhang, Pingbing Zuo, Nikolai Pogorelov
Heliospheric Influence On The Anisotropy Of Tev Cosmic Rays, Ming Zhang, Pingbing Zuo, Nikolai Pogorelov
Aerospace, Physics, and Space Science Faculty Publications
This paper provides a theory of using Liouville's theorem to map the anisotropy of TeV cosmic rays seen at Earth using the particle distribution function in the local interstellar medium (LISM). The ultimate source of cosmic ray anisotropy is the energy, pitch angle, and spatial dependence of the cosmic ray distribution function in the LISM. Because young nearby cosmic ray sources can make a special contribution to the cosmic ray anisotropy, the anisotropy depends on the source age, distance and magnetic connection, and particle diffusion of these cosmic rays, all of which make the anisotropy sensitive to the particle energy. …
A Numerical Simulation Of Solar Energetic Particle Dropouts During Impulsive Events, Yi Wáng, Gang Qin, Ming Zhang, Silvia Dalla
A Numerical Simulation Of Solar Energetic Particle Dropouts During Impulsive Events, Yi Wáng, Gang Qin, Ming Zhang, Silvia Dalla
Aerospace, Physics, and Space Science Faculty Publications
This paper investigates the conditions for producing rapid variations of solar energetic particle (SEP) intensity commonly known as "dropouts." In particular, we use numerical model simulations based on solving the focused transport equation in the three-dimensional Parker interplanetary magnetic field to put constraints on the properties of particle transport coefficients in both directions perpendicular and parallel to the magnetic field. Our calculations of the temporal intensity profile of 0.5 and 5 MeV protons at the Earth show that the perpendicular diffusion must be small while the parallel mean free path is long in order to reproduce the phenomenon of SEP …