Tangential electric fields in a drifting auroral arc

We report rocket-borne ion convection velocity and ground-based optical measurements in an early evening, equatorward drifting, NW-SE oriented auroral arc. Our measurements indicate a detailed correspondence between the normal component of the ion convection velocity (the component normal to the auroral arc) and the drift motion of the auroral arc. The two velocities were identical on a time scale of minutes, and correlated strongly with each other in smaller-scale temporal variations. The correspondence implies a near-zero tangential electric field in an auroral arc, in the frame of reference of the arc. Our observations have serious consequences on several auroral theories.

[1]  B. A. Whalen,et al.  Rocketborne observations of ion convection and electric fields in dayside and nightside visual auroral arcs , 1981 .

[2]  F. R. Harris,et al.  Preliminary results from Project Waterhole — an auroral modification experiment , 1981 .

[3]  B. A. Whalen,et al.  Observations of particle precipitation, electric field, and optical morphology of an artificially perturbed auroral arc: Project Waterhole , 1981 .

[4]  L. J. Cahill,et al.  Rocket observations at the northern edge of the eastward electrojet , 1980 .

[5]  G. S. Stiles,et al.  Prolonged radar observations of an auroral arc , 1980 .

[6]  B. A. Whalen,et al.  Thermal ion results from an experiment to produce artificially an ionospheric hole: Lagopedo Uno , 1979 .

[7]  Tetsuya Sato.  Auroral and equatorial two‐stream irregularities: Difference in nonlinear state , 1977 .

[8]  R. Vondrak,et al.  Radar observations of electric fields and currents associated with auroral arcs , 1977 .

[9]  A. Egeland,et al.  Auroral vector electric field and particle comparisons, 1, Premidnight convection topology , 1977 .

[10]  G. Haerendel,et al.  Electric field measurements in a major magnetospheric substorm , 1975 .

[11]  B. A. Whalen,et al.  Correlations of ionospheric electric fields and energetic particle precipitation , 1975 .

[12]  E. Wescott,et al.  The L = 6.6 Oosik Barium Plasma Injection Experiment and magnetic storm of March 7, 1972 , 1975 .

[13]  B. A. Whalen,et al.  Ionospheric ion flow velocities from measurements of the ion distribution function technique , 1974 .

[14]  G. Atkinson.  Auroral arcs: Result of the interaction of a dynamic magnetosphere with the ionosphere , 1970 .

[15]  J. D. Stolarik,et al.  Electric fields in the vicinity of auroral forms from motions of barium vapor releases. , 1969 .