" Charged-particle propagation in the interstellar medium," by Martin Weidl (Max-Planck-Institut für Plasmaphysik)

Date: 
Thursday, October 8, 2015 - 2:00pm to 3:00pm
Series: 
Plasma Seminars

Plasma Seminar

Physics and Astronomy Building (PAB) Room 4-330
Thursday, October 8, 2015
2-3PM

Guest Speaker: Martin Weidl (Max-Planck-Institut für Plasmaphysik)

Talk Title: "Charged-particle propagation in the interstellar medium"

Abstract:

In turbulent astrophysical systems, velocity fluctuations and magnetic-field fluctuations are often correlated. In the solar wind or in the interstellar medium, this implies that more or stronger Alfvén waves propagate opposite to the magnetic mean field than along it. This imbalance, known as 'cross helicity', has a dramatic influence on the heating and scattering of charged particles.

In order to investigate its effect, we have performed test-particle simulations of strongly cross-helical MHD turbulence. We study whether quasilinear predictions of the heating rate of charged particles are valid under realistic conditions, and compare quasilinear pitch-angle diffusion coefficients with test-particle scattering after one gyroperiod. Moreover, we elucidate the role of the magnetic moment for pitch-angle scattering on short timescales.

Event Attachments: 
Location: 
PAB 4-330