HR: 0800h
AN: SH51D-0294    [Abstracts]
TI: Collective behaviour of a System of Emitting Dust Particles
AU: Delzanno, G L
EM: delzanno@lanl.gov
AF: LANL, MS K717, Los Alamos, 87545 United States
AU: * Lapenta, G
EM: lapenta@lanl.gov
AF: LANL, MS K717, Los Alamos, 87545 United States
AB: In the present work we focus on the role of electron emission (either thermionic, secondary or photoelectric) in charging an object immersed in a plasma. Recent work [1] has shown how electron emission can fundamentally affect the shielding potential around the dust. In particular, depending on the physical parameters of the system, the shielding potential can develop an attractive potential well. The aim of the present work is two-fold. First, we will present a theory of the existence and properties of the attractive potential well to explain the conditions for the formation, as well as providing a description of the well in terms of Lennard-Jones (LJ) potentials. Second, we focus on the consequences of attraction among eqully charged dust particle and on the peculiar collective behaviour under the circumstances. Here, we present a series of simulations conducted with a new code designed to study a large system of weakly coupled dust particles, interacting with a LJ like potential. [1] G.L. Delzanno, G. Lapenta, M. Rosenberg, Phys. Rev. Lett., 92, 035002 (2004).
DE: 7827 Kinetic and MHD theory
DE: 7843 Numerical simulation studies
DE: 6015 Dust
DE: 6040 Origin and evolution
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting