Post-noon two-minute period pulsating aurora and their relationship to thedayside convection pattern

Poleward-moving auroral forms, as observed by meridian-scanning photometers , in the vicinity of the cusp region are generally assumed to be the optica l signature of flux transfer events. Another class of quasi-continuous, sho rt 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 th ese short period wave-like auroral emissions, the optical signature of boun dary plasma sheet precipitation in the region 1 field-aligned current syste m, are associated with ULF magnetohydrodynamic wave activity, which is obse rved simultaneously by ground magnetometer stations. This association with ULF wave activity is strengthened by the observation of several harmonic fr equencies in the pulsation spectrum, each an overtone of the fundamental st anding wave resonance frequency.