Simultaneous polar aurorae and modelled convection patterns in both hemispheres
2006 (English)In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 38, no 8, 1685-1693 p.Article in journal (Refereed) Published
We present an event study illustrating the relationships between plasma convection and polar auroral emissions, as well as illustrating the influence of the interplanetary magnetic field's y-component on theta aurora development in both hemispheres. Transpolar arcs (TPAs) are often observed during northward IMF with duskside (dawnside) formation of the TPA and dawnward (duskward) motion occurring when B-y changes from positive to negative in the northern (southern) hemisphere. POLAR UVI provides images in the northern hemisphere while DMSP provides ionospheric plasma flow and precipitating particle data in both hemispheres. Concurrent solar wind plasma and interplanetary magnetic field measurements are provided by the ACE satellite. Utilizing the satellite data as inputs, the Royal Institute of Technology (KTH) numerical model provides the high-latitude ionospheric electrostatic potential patterns in both hemispheres calculated at different times during the evolution of the theta aurora resulting from a variety of field-aligned current configurations associated with the changing global aurora. These model patterns are compared to the convection predicted by mapping the magnetopause electric field to the ionosphere using the Moscow State University's (MSU) paraboloid model of the magnetosphere. The model predicts that parallel electric fields are set up along the magnetic field lines projecting to the transpolar aurora. Their possible role in the acceleration of the auroral electrons is discussed.
Place, publisher, year, edition, pages
Elsevier, 2006. Vol. 38, no 8, 1685-1693 p.
theta aurora, transpolar arc, magnetosphere-ionosphere coupling, electric fields, plasma convection, acceleration voltage
IdentifiersURN: urn:nbn:se:kth:diva-37474DOI: 10.1016/j.asr.2005.04.105ISI: 000202988500018ScopusID: 2-s2.0-33846030169OAI: oai:DiVA.org:kth-37474DiVA: diva2:434003
QC 201607212011-08-122011-08-122016-07-21Bibliographically approved