Whistler wave dispersion measurements near the ion gyro frequency

Investigation of ion whistler waves under laboratory conditions is difficult because of the long wavelength. In the VINETA device electromagnetic waves around the ion gyro frequency have been successfully launched. For frequencies above the ion gyro frequency the waves are identified as R-waves. Below the ion gyro frequency the measurements cannot be explained by R-wave or L-wave dispersion alone. In a heuristic way the observed dispersion is described by the difference wavelength of R-wave and L-wave