 |
| Titel |
Analytical study of the energy rate balance equation for the magnetospheric storm-ring current |
| VerfasserIn |
A. L. Clúa de Gonzalez, W. D. Gonzalez |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 16, no. 11 ; Nr. 16, no. 11, S.1445-1454 |
| Datensatznummer |
250013541
|
| Publikation (Nr.) |
 copernicus.org/angeo-16-1445-1998.pdf |
|
|
|
|
|
| Zusammenfassung |
| We present some results of the analytical
integration of the energy rate balance equation, assuming that the input energy
rate is proportional to the azimuthal interplanetary electric field, Ey,
and can be described by simple rectangular or triangular functions, as
approximations to the frequently observed shapes of Ey,
especially during the passage of magnetic clouds. The input function is also
parametrized by a reconnection-transfer efficiency factor α (which
is assumed to vary between 0.1 and 1). Our aim is to solve the balance equation
and derive values for the decay parameter τ compatible with the
observed Dst peak values. To facilitate the analytical integration we
assume a constant value for τ through the main phase of the storm. The
model is tested for two isolated and well-monitored intense storms. For these
storms the analytical results are compared to those obtained by the numerical
integration of the balance equation, based on the interplanetary data collected
by the ISEE-3 satellite, with the τ values parametrized close to those
obtained by the analytical study. From the best fit between this numerical
integration and the observed Dst the most appropriate values of
τ are then determined. Although we specifically focus on the main
phase of the storms, this numerical integration has been also extended to the
recovery phase by an independent adjust. The results of the best fit for the
recovery phase show that the values of τ may differ drastically from
those corresponding to the main phase. The values of the decay parameter for the
main phase of each event, τm, are found to be very
sensitive to the adopted efficiency factor, α, decreasing as this
factor increases. For the recovery phase, which is characterized by very low
values of the power input, the response function becomes almost independent of
the value of α and the resulting values for the decay time
parameter, τr, do not vary greatly as α
varies. As a consequence, the relative values of α between the main
and the recovery phase, τm/τr,
can be greater or smaller than one as α varies from 0.1 to 1. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|