M. J. Pueschel

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There is a potential hazard during examinations of patients with attached or implanted long conductors, e.g. ECG leads: an MR exam of the lumbar spine of a patient was performed in a 1.5-T scanner under ECG monitoring using equipment marked as MR compatible. Standard cabling of 370-cm length was guided without loops from the electrodes through the caudal(More)
Analytical and numerical work is used in tandem to address the problem of turbulent transport of energetic ions in magnetized plasmas. It is shown that orbit averaging is not valid under rather generic conditions, and that perpendicular decorrelation effects lead to a slow 1=E decay of the electrostatic particle diffusivity of beam ions, while the(More)
Nonlinear electromagnetic stabilization by suprathermal pressure gradients found in specific regimes is shown to be a key factor in reducing tokamak microturbulence, augmenting significantly the thermal pressure electromagnetic stabilization. Based on nonlinear gyrokinetic simulations investigating a set of ion heat transport experiments on the JET tokamak,(More)
The nonlinear dynamics of microtearing modes in standard tokamak plasmas are investigated by means of ab initio gyrokinetic simulations. The saturation levels of the magnetic field fluctuations can be understood in the framework of a balance between (small poloidal wave number) linear drive and small-scale dissipation. The resulting heat transport is(More)
Numerical simulations of electron temperature gradient ETG turbulence are presented that characterize the ETG fluctuation spectrum, establish limits to the validity of the adiabatic ion model often employed in studying ETG turbulence, and support the tentative conclusion that plasma-operating regimes exist in which ETG turbulence produces sufficient(More)
We report on the resolution of a significant discrepancy between published continuum-code simulations and subsequent global particle-in-cell (PIC) simulations of electron-temperature-gradient (ETG) turbulence. Our investigations, using gyrokinetic δf -PICand continuum-code simulations and analytical theory, strongly support the conclusion from the earlier(More)