Observations of velocity shear driven plasma turbulence


  • P. M. Kintner Jr.


Electrostatic and magnetic turbulence observations from Hawkeye 1 during the low-altitude portion of its elliptical orbit over the southern hemisphere are presented. The magnetic turbulence is confined near the auroral zone and is similar to that seen at higher altitudes by Heos 2 in the polar cusp. The electrostatic turbulence is composed of a background component with a power spectral index of 1.89 ± 0.26 and an intense component with a power spectral index of 2.80 ± 0.34. The intense electrostatic turbulence and the magnetic turbulence correlate with velocity shears in the convective plasma flow. Since velocity shear instabilities are most unstable to wave vectors perpendicular to the magnetic field, the shear correlated turbulence is anticipated to be two-dimensional in character and to have a power spectral index of 3, which agrees with that observed in the intense electrostatic turbulence.