
Electron density and electron neutral collision frequency in the ionosphere using plasma impedance probe measurements
Author(s) -
Spencer E.,
Patra S.,
Andriyas T.,
Swenson C.,
Ward J.,
Barjatya A.
Publication year - 2008
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2007ja013004
Subject(s) - collision frequency , electron density , computational physics , electron , ionosphere , atomic physics , physics , electrical impedance , plasma , plasma parameters , electron temperature , incoherent scatter , langmuir probe , plasma diagnostics , geophysics , nuclear physics , quantum mechanics
Swept Impedance Probe measurements in a sporadic E layer observed during the Sudden Atomic Layer (SAL) sounding rocket mission are analyzed to obtain absolute electron densities and electron neutral collision frequencies accurately. Three sets of upleg and downleg impedance data are selected for the analysis. Initial estimates of the plasma parameters are obtained through a least mean square fit of the measured impedance data against the analytical impedance formula Z B ( f ) of Balmain (1969). These initial parameters are used as a starting point to drive a finite difference computational model of an antenna immersed in a plasma called PF‐FDTD. The parameters are then tuned until a close fit is obtained between the measured impedance data and the numerical impedance data calculated by the PF‐FDTD simulation. The electron densities obtained from the simulation were close to those obtained from the IRI 2001 model. The electron neutral collision frequencies obtained from the more accurate PF‐FDTD simulation were up to 20% lower than the values predicted by Balmain's formula. The obtained collision frequencies are also lower than the quiet time values predicted by Schunk and Nagy (2000) when used in conjunction with neutral densities and electron temperature from the Mass Spectrometer Incoherent Scatter Radar Extended‐90 model.