New methods for suppressing numerical Cherenkov instabilities in relativistic particle-in-cell simulations
Abstract
We present two novel methods for suppressing numerical Cherenkov instabilities in relativistic particle-in-cell simulations The WT scheme, a piecewise polynomial force interpolation scheme with time-step dependency, is proposed to remove the lowest order numerical Cherenkov instability (NCI) growth rate for arbitrary time steps allowed by the Courant condition. While NCI from higher order resonances is still present, the numerical tests show that for smaller time steps, the numerical instability grows much slower than using the optimal time step found in previous studies. _A semi-implicit Maxwell solver derived from finite element method with O(N) computing cost is developed to improve the numerical dispersion properties
Research presented in this paper was supported by the Center for Space and Earth Science(CSES) program and Laboratory Directed Research and Development(LDRD) program of Los Alamos National Laboratory(LANL). The simulations were performed with LANL Institutional Computing which is supported by the U.S. Department of Energy National Nuclear Security Administration under Contract No. 89233218CNA000001, and with the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation(NSF) Grant Number ACI-1548562.- Publication:
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APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- 2019
- Bibcode:
- 2019APS..DPPY10065L