Ring current model of the naphthalene molecule

<p>Particle precipitation originated from the magnetosphere provides important energy source to the upper atmosphere, leading to ionization and enhancement of conductivity, which in turn changes the electric potential in the MI system to influence the plasma convection in the magnetosphere. In this study, we simulate ring current particle precipitation caused by several important loss mechanisms, including electron precipitation due to whistler wave scattering, ion precipitation due to EMIC wave diffusion and field line curvature scattering. These physical mechanisms are implemented in the kinetic ring current model via diffusion equation with associated pitch angle diffusion coefficients. The precipitation is subsequently input to a two-stream transport model at the top of ionosphere in order to examine its impact on the ionsopheric conductivity. It is found that during intense storm time, electron precipitation of tens of keV dominates in the dawn sector and leads to significant enhancement of conductivity at low altitudes. On the other hand, proton precipitation on the nightside mostly occurs for energy below 10 keV, and contributes to ionization above 100 km, resulting in enhancement of conductivity there. Consequently, the height profile of both Pedersen and Hall conductivity exhibits two layers, potentially complicating the current closure in the ionosphere system.</p>

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The ring current model of the pentaprismane molecule

Journal of Computational Chemistry ◽

10.1002/jcc.21739 ◽

2011 ◽

Vol 32 (8) ◽

pp. 1599-1611 ◽

Cited By ~ 9

Author(s):

Stefano Pelloni ◽

Raphaël Carion ◽

Vincent Liégeois ◽

Paolo Lazzeretti

Keyword(s):

Ring Current ◽

Current Model

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Inconsistency of the ring-current model for the cyclopropenyl cation

Chemical Physics Letters ◽

10.1016/0009-2614(81)85072-5 ◽

1981 ◽

Vol 80 (3) ◽

pp. 533-536 ◽

Cited By ~ 37

Author(s):

Paolo Lazzeretti ◽

Riccardo Zanasi

Keyword(s):

Ring Current ◽

Current Model

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Storm-time ring current: model-dependent results

Annales Geophysicae ◽

10.5194/angeo-30-177-2012 ◽

2012 ◽

Vol 30 (1) ◽

pp. 177-202 ◽

Cited By ~ 23

Author(s):

N. Yu. Ganushkina ◽

M. W. Liemohn ◽

T. I. Pulkkinen

Keyword(s):

Magnetic Field ◽

Electric Field ◽

Boundary Conditions ◽

Electric Fields ◽

Ring Current ◽

Current Model ◽

Current Data ◽

Storm Events ◽

Boundary Location ◽

Field Lines

Abstract. The main point of the paper is to investigate how much the modeled ring current depends on the representations of magnetic and electric fields and boundary conditions used in simulations. Two storm events, one moderate (SymH minimum of −120 nT) on 6–7 November 1997 and one intense (SymH minimum of −230 nT) on 21–22 October 1999, are modeled. A rather simple ring current model is employed, namely, the Inner Magnetosphere Particle Transport and Acceleration model (IMPTAM), in order to make the results most evident. Four different magnetic field and two electric field representations and four boundary conditions are used. We find that different combinations of the magnetic and electric field configurations and boundary conditions result in very different modeled ring current, and, therefore, the physical conclusions based on simulation results can differ significantly. A time-dependent boundary outside of 6.6 RE gives a possibility to take into account the particles in the transition region (between dipole and stretched field lines) forming partial ring current and near-Earth tail current in that region. Calculating the model SymH* by Biot-Savart's law instead of the widely used Dessler-Parker-Sckopke (DPS) relation gives larger and more realistic values, since the currents are calculated in the regions with nondipolar magnetic field. Therefore, the boundary location and the method of SymH* calculation are of key importance for ring current data-model comparisons to be correctly interpreted.

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