Numerical study of mode conversion between lower hybrid and whistler waves on short-scale density striations

We present a theoretical and numerical study of linear mode conversion of lower hybrid waves interacting with short-scale density striations in the Earth's ionosphere. The efficiency of the conversion process is investigated for different sets of parameters such as the angle of incidence, the wavelength of the lower hybrid wave, and the size of the striation. It is found that the most efficient whistler generation occurs at a critical angle of incidence where the whistler waves are driven resonantly along the density striations, and when the product of the striation width and the wave number of the lower hybrid wave is of the order unity. It is suggested that whistlers generated as a byproduct of upper hybrid F-region ionospheric heating can be observed on the ground and by satellites. The generated whistlers could be important for the precipitation of energetic electrons in the radiation belts.