Statistical characterization of the American sector subauroral polarization stream using incoherent scatter radar

摘要: [1] We examine Millstone Hill incoherent scatter radar data collected over two solar cycles between 1979 and 2001 to determine average characteristics features of storm time ion velocity flux transport in the American sector midlatitude ionosphere. We use 1100 azimuth scans identified as containing enhanced westward velocities associated with subauroral polarization stream (SAPS), covering 12–06 magnetic local (MLT) 50°–68° invariant latitude for weak moderate disturbance levels Dst from 50 −200 nT. find peak location SAPS flow channels decreases linearly both MLT a very good degree correlation. also first fluxes, which material magnitude 3 × 1013 1014 m−2 s−1 manner nearly activity level. This invariance is maintained by an inverse relationship electron density magnitudes increasing Dst. Westward log are maximum dusk decrease MLT, smoothly varying across terminator. Finally, distributions show that afternoon swept earlier values, delivering O+ cusp region. In contrast, streams post terminator sectors fixed east-west Sun-Earth inertial frame, effectively maintaining entrained fluxes at same MLT.