J. A. Cohen

TL;DR: In this paper, the authors examined possible correlations between occurrences of nighttime E-region plasma line enhancements over Arecibo and 40.75 kHz NAU emissions, indicating that the rate of PL event detections increased by a factor of 2.8 after NAU turn-on.

TL;DR: In this article, the authors proposed that NAU-generated 40.75 kHz whistler-mode waves are intense enough to excite lower hybrid waves and zero-frequency field-aligned ionospheric irregularities over Arecibo.

TL;DR: In this paper, the results of ionospheric HF heating experiments to generate artificial acoustic-gravity waves (AGW) and traveling ionosphere disturbances (TID) were conducted at the High-frequency Active Auroral Research Program facility in Gakona, Alaska.

TL;DR: In this paper, the authors used the intensity-modulated HF heating waves to interact with electrojet currents for the generation of VLF waves, and observed the enhancement of spread-E irregularities at electrojet current altitudes due to the amplitude-modified heater wave.

TL;DR: In this paper, the shape of large plasma sheets, generated by vertically transmitted HAARP HF heater waves in several experiments conducted in Gakona, Alaska, was investigated. And the theoretical prediction was supported by measurements of ionosonde data (namely ionograms), range-time-intensity (RTI) plots of UHF and HF backscatter radars, as well as magnetometer data analyses.