Correlation between Poynting flux and soft electron precipitation in the dayside polar cap boundary regions.
Observations have revealed large Poynting flux and soft electron precipitation around the cusp region, which have strong impacts on the polar ionosphere/thermosphere. Simulations also confirmed that Poynting flux and soft electron precipitation significantly change the neutral density and dynamics around the dayside polar cap boundary regions. However, no detailed study has been conducted to show if they should coincide with each other or not. Our analysis of Defense Meteorological Satellite Program (DMSP) satellite data reveals a complex correlation between them. Poynting flux and soft particle precipitation are coincident in some cases (match cases), but a clear displacement between them can also be identified in others (nonmatch cases). In the 29 cusp crossings from F13 we investigated, the ratio between nonmatch and match cases is close to 1:4. In nonmatch cases, the displacement between the Poynting flux enhancement and soft particle precipitation enhancement can be as large as 1° in geomagnetic latitude.
Department of Physics University of Texas at Arlington Arlington Texas USA.
Yue
Y
Deng
Department of Physics University of Texas at Arlington Arlington Texas USA.
Cheng
C
Sheng
Space Vehicles Directorate Air Force Research Laboratory Albuquerque New Mexico USA.
Yi-Jiun
YJ
Su
Department of Physics University of Texas at Dallas Richardson Texas USA.
Marc R
MR
Hairston
Aerospace Engineering Sciences University of Colorado Boulder Boulder Colorado USA.
Delores
D
Knipp
Space Vehicles Directorate Air Force Research Laboratory Albuquerque New Mexico USA.
Cheryl Y
CY
Huang
Space Vehicles Directorate Air Force Research Laboratory Albuquerque New Mexico USA.
Daniel
D
Ober
National Oceanic and Atmospheric Administration Boulder Colorado USA.
Rob J
RJ
Redmon
Department of Physics University of Texas at Dallas Richardson Texas USA.
Robin
R
Coley
Polar cap boundary; Poynting flux; coincide; cusp; dayside; particle precipitation