Simulating the cleft ion fountain at polar perigee altitudes

Details Simulating the cleft ion fountain at polar perigee altitudes Simulating the cleft ion fountain at polar perigee altitudes

Mar 2005

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005jastp..67..465t&link_type=abstract

Journal of Atmospheric and Solar-Terrestrial Physics, Volume 67, Issue 5, p. 465-477.

Physics

12

Scientific paper

A dynamic fluid semi-kinetic (DyFK) model is used to simulate the cleft ion fountain. Ion field-aligned flows are modeled for a flux tube convecting along an empirical model specified convection trajectory across the polar ionosphere from the cusp/cleft region. In this DyFK model, the collision-dominated portion of the flux tube is treated with a moment-based fluid model for altitudes from 120 to 1100 km, while a generalized semi-kinetic model is used for the 800 km to 3 RE altitude region. Convection-driven frictional ion heating and the effects of cusp/cleft soft electron precipitation in the F region/topside ionosphere, and centrifugal acceleration of ions and wave-driven transverse ion heating at high altitudes, are incorporated into the present simulations of the ion field-aligned transport. The modeled evolution of the O+ flow parameters at 5500 km altitude exhibits typical patterns for the cleft ion fountain: O+ field-aligned flows are upward over the dayside cusp/cleft and remain upward for 5 or more degrees latitude into the polar cap, with decreasing magnitude towards the pole; the flows turn downward at about 86° invariant latitude and tend to increase in magnitude (downward) across the polar cap from dayside to nightside; the O+ density also displays apparent day night asymmetry with higher density on the dayside. The simulated field-aligned flow pattern is in qualitative agreement with the observations from the thermal ion dynamics experiment (TIDE) during a Polar satellite southern perigee pass. The simulated ion densities and field-aligned fluxes are in general consistent with those observed. It is also shown in systematic simulations that the day night asymmetry of the O+ density across the polar cap from dayside to nightside may be directly controlled by the cleft ion fountain, while the H+ density asymmetry is probably caused by day night variations in solar illumination.

Affiliated with

Also associated with

No associations

Rating

Simulating the cleft ion fountain at polar perigee altitudes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Simulating the cleft ion fountain at polar perigee altitudes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Simulating the cleft ion fountain at polar perigee altitudes will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1219428