Description:The use of Grid computing for space weather forecast by using advanced models of particle acceleration
Abstract:The build-up of intense particle radiation during geospace magnetic storms is among the core space weather issues of interest and concern to scientists, engineers and users. Storm-time plasma acceleration is driven by the large-scale convection electric field and the substorm-induced electric fields in the earth’s magnetosphere. The relative influence of the two drivers on the development of the storm-time ring current is a topic of this study. The difference in energization between oxygen and hydrogen ions is one of the interests also pursued within this application.
The application needs to model substorm events under storm-time conditions and to calculate particle motions during storm time substorms.
For this reason the work is carried out on a three-dimensional dynamic ion-tracing model.
The geomagnetic field used is simulated through the Tsyganenko model, which gives a description of the average magnetic field configuration for 6 different levels of geomagnetic activity. It includes contributions from external sources such as the ring current, the magnetotail current system, the magnetopause currents and the large-scale system of field-aligned currents.
The large-scale steady convection electric field in the magnetosphere is calculated by the Volland-Stern model. It has been arranged to fit most general features of electric fields observed by polar orbiting satellites.
The electric field induced by a transition of the geomagnetic field, from an initial level to a final one, more or less disturbed, is derived by the vector potential technique of Delcourt.
By using this code we can follow the transport and acceleration of ions to the inner magnetosphere and their final contribution to the ring current development.
In order to produce a more representative and realistic view of the ring current, a large number of particles is required. It is obvious that the more particles used for each simulation, the more computational time is needed. The investigation of transport and the mechanism of ener