Article draft. Author list indicative and roughly corresponds to amount of contribution to the article to date.Abstract. Ps 6 magnetic disturbances and associated optical
forms known as omega bands are usually associated
with the morning sector. Some evidence for similar phenomenology
in the evening sector has been presented by
Solovyev et al. (1999). We confirm and extend those results
with high time resolution magnetic and imaging observations
from Athabasca University Geophysical Observatory
for an event that took place on July 27, 2003, along with conjugate
hemisphere imaging from the Polar spacecraft. The
observed signatures indicate sunward drift (westward in the
evening sector). Magnetic perturbations feature negative Y
and transitional Z indicating westward passage of poleward
equivalent currents overhead. As has been suggested by Connors
et al. (2003) to be often the case for morning sector Ps
6/omega bands, initiation of the evening sector event coincided
with substorm onset. From optical and magnetic data
we obtain consistent results for the drift rate of the forms,
which changed during the event. An inner magnetospheric
source is suggested, with triggering of the onset by an increase
in solar wind speed
