Ps 6 disturbances and associated omega bands are often considered to be part of the phenomenology of the recovery phase of substorms. We note cases of the initiation of Ps 6 activity at or very near the time of onset, either of a substorm expansive phase, a pseudobreakup, or a poleward border intensification. Thus, we claim that Ps 6 disturbances need not be viewed primarily as phenomena of the recovery phase. This produces both the challenge of explaining Ps 6 within a broader context and the opportunity to use Ps 6 observations to better understand magnetospheric phenomenology, including expansive phase onsets. We further examine the position of the causative currents for Ps 6 and find that they may be located at either the equatorward or poleward border of the auroral oval, or within it. In the first case, the relationship of expansive phase onset and time delay to Ps 6 initiation appears to be very short. In the latter case, there is an association with poleward border intensification, but with a measurable time delay. We present HF radar data to discuss how the electric field at onset time favors the growth of Ps 6 current systems.

Key words. Magnetospheric physics (Storms and substorms; Electric fields; MHD waves and instabilities)

+More

electric field physics recovery pseudobreakup substorms electric fields mhd waves and instabilities expansive phase onset omega bands equatorward poleward border intensification hf radar data magnetospheric phenomenology the auroral oval ps 6 disturbances

M. Connors,G. Rostoker,G. Sofko,R. L. McPherron,M. G. Henderson,.Ps 6 disturbances: relation to substorms and the auroral oval. 21 (2),.

M. Connors,G. Rostoker,G. Sofko,R. L. McPherron,M. G. Henderson,"Ps 6 disturbances: relation to substorms and the auroral oval" 21

M. Connors,G. Rostoker,G. Sofko,R. L. McPherron,M. G. Henderson,"Ps 6 disturbances: relation to substorms and the auroral oval"