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A compound diffusion model for cosmic rays accelerated in corotating interaction regions, simulating charged particle transport in turbulent magnetic fields with adjustable spectral indexes and intermittent regulation. The model includes equations of motion, resonant interactions, and tempered Levy walks for parallel transport. Comparison of simulated and analytical results, superdiffusion of electrons, and plasma and particle profiles.
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Generalized compound diffusion model of solar cosmic rays accelerated in corotating interaction region VladimirUchaikin, RenatSibatov, Alexander Byzykchi Ulyanovsk State University, Russia The 2nd International Conference on Particle Physics and Astrophysics
Simulation of charged particle transport in turbulent MF Pucci, F. et al. (2016). MNRAS, 459(3), 3395-3406. Turbulent magnetic field The model builds up a turbulent magnetic field as a superposition of space-localized fluctuations at different spatial scales. The resulting spectrum is isotropic with an adjustable spectral index. The model allows them to reproduce a spectrum broader than four decades, and to regulate the level of intermittency through a technique based on the p-model.
Simulation of charged particle transport in turbulent MF Pucci, F. et al. (2016). MNRAS, 459(3), 3395-3406. Equations of motion The guiding center motion Resonant interactions and magnetic mirroring
Parallel and perpendicular diffusion coefficients Pucci, F. et al. (2016). MNRAS, 459(3), 3395-3406. Tempered Levy Walk for parallel transport
Levy walks and Brownian motion Distribution of path lengths between reflections Brownian motion Superdiffusion
Tempered Levy flights: space-time trajectories
Inverse problem Second moment of the random walk with finite velocity Second moment of the random walk with finite velocity
Comparison of simulated and analytical results Tempered Levy Walk for parallel transport
Simulation of the tempered Levy walk: evolution of the diffusion packet
Magnetic field line random walk Bieber et al. Mean square displacement Fractional Brownian motion Perpendicular diffusion coefficient Pucci et al 2016
Protons and electrons accelerated by corotating interaction region • Perri, S., & Zimbardo, G. (2007). • Perri, S., & Zimbardo, G. (2009). • Sugiyama, T., & Shiota, D. (2011). x
Superdiffusion from analysis of energetic particle profiles measured by spacecraft Normal diffusion – exponential decay of intensity Anomalous diffusion – power law decay of intensity
Superdiffusion from analysis of energetic particle profiles measured by spacecraft Electron transport is superdiffusive. Proton transport is normal diffusive. (Perri and Zimbardo, Adv. Spa. Res. 2009)
Superdiffusion of electrons Event of October 11, 1992 Dt=|t-tsh| Power law J=A(Dt)-g Exponential J=K exp(-GDt)
Specification of the Green function Uchaikin, V., Sibatov, R., & Byzykchi, A. (2014). Commun in Appl and Ind Math, 6(1).
Plasma and energetic particle profiles for the Ulysses shock crossing on 1992 October 11. From top to bottom, panels show 1 h averages of plasmaradial velocity, plasma temperature (from SWOOPS, PI D. McComas), proton fluxes and electron fluxes (from HI-SCALE LEFS 60, PI L. Lanzerotti).The vertical dashed line indicates the reverse shock crossing time. Energy channels as indicated.
The same technique was applied to CME driven shock waves by Sugiyama and Shiota, ApJL, 2011: ACE data for December 13, 2006 CME shock
Sugiyama, T., & Shiota, D. (2011). Gray curves in panels show the flux of the energetic particles in the upstream of the shock. The horizontal axis is the time interval |Δt| between the observation time t and the shock crossing time