Berlin 2014 – wissenschaftliches Programm

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P: Fachverband Plasmaphysik

P 22: Helmholtz Graduate School for Plasma Physics II

P 22.1: Hauptvortrag

Donnerstag, 20. März 2014, 10:30–11:15, SPA HS202

Cosmic rays — •Reinhard Schlickeiser — Institut für Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universität Bochum, 44780 Bochum

Cosmic rays denote a population of cosmic charged particles with individual particle energies up to 10²⁰ eV. The nonthermal emission processes of cosmic ray nucleons and electrons dominate the photon emission in many astrophysical sources. In the tutorial the fundamentals of cosmic ray astrophysics are reviewed, stressing the importance of electromagnetic acceleration and transport processes in magnetized systems (as the interplanetary and interstellar medium) with ordered magnetic fields B₀≫ δ B≫ δ E being much greater than the turbulent magnetic and electric field components. The ordering B₀≫ δ B≫ δ E, necessary for explaining the observed near isotropy of cosmic rays, is the basis for a perturbation scheme leading to the modified diffusion-convection cosmic ray transport equation that describes all electromagnetic acceleration and transport processes discussed today. In unmagnetized cosmic systems (such as the intergalactic medium) a similar peturbation scheme based on δ B≫ δ E can be developed. Understanding cosmic (δ B,δ E)-fluctuations in space plasmas therefore is of crucial importance e.g. the role of collective and noncollective modes and wave-like, weakly-propagating and aperiodic fluctuations. The similarities and differences to the transport theory in magnetized fusion plasmas are highlighted.