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arXiv · 1407.1645

Screened Coulomb potential in a flowing magnetized plasma

Jan-Philip Joost·Patrick Ludwig·Hanno Kählert·Christopher Arran·Michael Bonitz
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Abstract

The electrostatic potential of a moving dust grain in a complex plasma with magnetized ions is computed using linear response theory, thereby extending our previous work for unmagnetized plasmas [P. Ludwig et al., New J. Phys. 14, 053016 (2012)]. In addition to the magnetic field, our approach accounts for a finite ion temperature as well as ion-neutral collisions. Our recently introduced code \texttt{Kielstream} is used for an efficient calculation of the dust potential. Increasing the magnetization of the ions, we find that the shape of the potential crucially depends on the Mach number $M$. In the regime of subsonic ion flow ($M<1$), a strong magnetization gives rise to a potential distribution that is qualitatively different from the unmagnetized limit, while for $M>1$ the magnetic field effectively suppresses the plasma wakefield.

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Jan-Philip Joost, Patrick Ludwig, Hanno Kählert, Christopher Arran, Michael Bonitz. 2014-07-07. Screened Coulomb potential in a flowing magnetized plasma. https://doi.org/10.1088/0741-3335%2F57%2F2%2F025004

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