Reconciliation of rocket-based magnetic field measurements in the equatorial electrojet with classical collision theory

Abstract

We provide an explanation for a long-standing (more than 35 years) discrepancy between theory and rocket experiments concerning the peak height of the electrojet current and the magnitude of magnetic field perturbation. The arbitrary correction of the electron-neutral collision frequency by a factor of 4, which has been used to explain these problems, is not necessary if the field line–integrated conductivities are used. Recent research using ground-based magnetometers and CHAMP have also used this constant connection to classical collision theory. These methods arbitrarily change the electron-neutral collision frequency. A field line–integrated theoretical study of the electrojet by G. Haerendel and J. V. Eccles, implemented in this paper, explains the height of the electrojet using classical collision frequency. Furthermore, we argue that since the correction factor is independent of the driving electric field, it is unlikely that anomalous electron collision frequency due to a nonlinear plasma instability (gradient drift) is involved.