Statistical Investigation of the Frequency Dependence of the Chorus Source Mechanism of Plasmaspheric Hiss
Nigel P. Meredith, Jacob Bortnik, R. B. Horne, Wen Li, Xiaochen Shen
Abstract
Abstract We use data from eight satellites to statistically examine the role of chorus as a potential source of plasmaspheric hiss. We find that the strong equatorial (| λ m | < 6°) chorus wave power in the frequency range 50 < f < 200 Hz does not extend to high latitudes in any magnetic local time sector and is unlikely to be the source of the low frequency plasmaspheric hiss in this frequency range. In contrast, strong equatorial chorus wave power in the medium frequency range 200 < f < 2,000 Hz is observed to extend to high latitudes and low altitudes in the pre‐noon sector, consistent with ray tracing modeling from a chorus source and supporting the chorus to hiss generation mechanism. At higher frequencies, chorus may contribute to the weak plasmaspheric hiss seen on the dayside in the frequency range 2,000 < f < 3,000 Hz band but is not responsible for the weak plasmaspheric hiss on the nightside in the frequency range 3,000 < f < 4,000 Hz.