Post-noon two-minute period pulsating aurora and their relationship to the dayside convection pattern
journal contributionposted on 24.10.2012, 09:05 by Stephen E. Milan, Tim K. Yeoman, Mark Lester, J. Moen, P. E. Sandholt
Poleward-moving auroral forms, as observed by meridian-scanning photometers, in the vicinity of the cusp region are generally assumed to be the optical signature of flux transfer events. Another class of quasi-continuous, short period (1-2 min) wave-like auroral emission has been identified, closely co-located with the convection reversal boundary in the post-noon sector, which is similar in appearance to such cusp aurora. It is suggested that these short period wave-like auroral emissions, the optical signature of boundary plasma sheet precipitation in the region 1 field-aligned current system, are associated with ULF magnetohydrodynamic wave activity, which is observed simultaneously by ground magnetometer stations. This association with ULF wave activity is strengthened by the observation of several harmonic frequencies in the pulsation spectrum, each an overtone of the fundamental standing wave resonance frequency.
CitationANNALES GEOPHYSICAE-ATMOSPHERES HYDROSPHERES AND SPACE SCIENCES, 1999, 17 (7), pp. 877-891
Published inANNALES GEOPHYSICAE-ATMOSPHERES HYDROSPHERES AND SPACE SCIENCES
PublisherEuropean Geosciences Union (EGU), Copernicus Publications, Springer Verlag (Germany)
Science & TechnologyPhysical SciencesAstronomy & AstrophysicsGeosciencesMultidisciplinaryMeteorology & Atmospheric SciencesGeologymagnetospheric physics (auroral phenomenamagnetopausecuspand boundary layersMHD waves and instabilities)LATITUDE BOUNDARY-LAYERHF RADAR OBSERVATIONSFLUX-TRANSFER EVENTSHYDROMAGNETIC-WAVESALFVEN WAVESFIELD LINESCUSPSIGNATURESPRECIPITATIONFORMS