Statistical study of emissions near f(p) and 2 f(p) in the dayside and nightside auroral region and polar cap

We examine a large data base of relatively intense plasma waves observed at frequencies near the plasma frequency f(p) and near 2 f(p) (the PF and H components, respectively) by the DE 1 spacecraft. These data are from a period of approximately 2.5 yr, corresponding to over 2600 orbits, and specifically include observations in the auroral regions and over the polar caps. The data show PF and H emissions during approximately 100 passes, or approximately 4 percent of the passes. The PF and H emissions are observed exclusively at latitudes corresponding to the polar cap and auroral regions, with a clear preponderance for the polar cap. The emissions are observed at all magnetic local times but with a concentration near local midnight. No association is observed with the Ap and Dst indices. Polarization data available from a subset of these passes show that PF emissions have a polarization that is consistent with whistler mode on 10 passes and with the z mode on 25 passes. (Author)