Polar cap patch segmentation of the tongue of ionization in the morning convection cell

[1] Two types of poleward moving plasma concentration enhancements (PMPCEs) were observed during a sequence of pulsed reconnection events, both in the morning convection cell: Type L (low density) was associated with a cusp flow channel and seems likely to have been produced by ionization associated with particle precipitation, while Type H (high density) appeared to originate from the segmentation of the tongue of ionization by the processes which produced the Type L events. As a result, the Type L and Type H PMPCEs were interspersed, producing a complex density structure which underlines the importance of cusp flow channels as a mechanism for segmenting and structuring electron density in the cusp and shows the necessity of differentiating between at least two classes of electron density patches. Citation: Zhang, Q.-H., B.-C. Zhang, J. Moen, M. Lockwood, I. W. McCrea, H.-G. Yang, H.-Q. Hu, R.-Y. Liu, S.-R. Zhang, and M. Lester (2013), Polar cap patch segmentation of the tongue of ionization in the morning convection cell, Geophys. Res. Lett., 40, 2918–2922, doi:10.1002/grl.50616.