HR: 1340h
AN: SH53A-1238    [Abstracts]
TI: Magnetoacoustic Solitons in High-β Plasmas
AU: * Simon, B
EM: B.Simon@warwick.ac.uk
AF: Space and Astrophysics, University of Warwick, Coventry, CV4 7AL United Kingdom
AU: Nakariakov, V M
EM: V.Nakariakov@warwick.ac.uk
AF: Space and Astrophysics, University of Warwick, Coventry, CV4 7AL United Kingdom
AU: Chapman, S C
EM: S.C.Chapman@warwick.ac.uk
AF: Space and Astrophysics, University of Warwick, Coventry, CV4 7AL United Kingdom
AU: Dendy, R O
EM: R.O.Dendy@ukaea.org.uk
AF: Culham Science Centre, UKAEA fusion, Abingdon, OX12 8QU United Kingdom
AB: Solitary wave solutions arise naturally from one dimensional Hall-Magnetohydrodynamic equations. These solutions have been recently identified as models for slow-mode solitary structures observed in the magnetosheath and other magnetospheric boundary layers, and as a model for magnetic holes (MH), which are localized depressions of magnetic field observed in the solar wind. We perform a parametric study of highly oblique magnetoacoustic solitons in frames of Stasiewicz's analytical model [1], taking plasma pressure anisotropy into account. We study the stability of these structures using a 1.5D hybrid code. In particular, we focus on magnetic structures in a high-β (ratio of kinetic to magnetic pressures) plasmas. These plasma conditions are typical in the region around MHs, and the study of stability is vital in verifying the theory that MHs are manifestations of such solitons. Our simulations are aimed at studying linear magnetic holes, where there is almost no variation in direction of the ambient magnetic field direction. The majority of MHs discovered in space plasmas fall into this category. [1] Stasiewicz,K., Phys. Rev. Lett., 93, 125004, 2004
DE: 3285 Wave propagation (0689, 2487, 4275, 4455, 6934)
DE: 4455 Nonlinear waves, shock waves, solitons (0689, 2487, 3280, 3285, 4275, 6934, 7851, DE: 7836 MHD waves and instabilities (2149, 2752, 6050)
DE: 7852 Solitons and solitary waves (4455)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005