New optical results from HAARP: E layer emissions and quantitative aspect angle dependence

We report a completely new case of km-scale E-region irregularities created or illuminated by the HAARP transmitter and appearing in the 557.7 nm green line. The new data confirm and extend the original 2004 observations of these "speckles," and rule out ULF resonances or long-period pulsations in favor of direct transmitter control, which is conclusively demonstrated by the timing of the transmitter pulses. The features exhibit persistence over several minutes and are relatively insensitive to absolute transmitter power, occurring well away from the beam center. New F-region results based on modeling of the O 1D emission lifetime have allowed a quantitative map of 630.0 nm optical emissions to be derived for the first time as a function of transmitter power and angle relative to the magnetic field. This shows the magnetic zenith spot to account for just over half of the peak emission, with a broader distribution centered between magnetic and true zeniths accounting for just under half. Raytracing suggests that propagation does not explain the sharp cutoff in F-region emissions observed away from zenith.