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Similar to whistler mode chorus, Z-mode emission is an efficient diffusive scatterer of electrons possibly resulting in resonant acceleration. We present results of a survey of both the low-band (5 kHz) and for the first time the high-band (20 kHz) intensity of these emissions, based on over 11 years of Cassini Radio and Plasma Wave Science instrument data including nine ring-grazing orbits and two proximal orbits, which occurred at the end of the mission. We distinguish these emissions using density and polarization measurements and calculate the mean intensity as a function of frequency and spatial coordinates. We find that the average low-band Z-mode intensity peak is P-0 similar to 7 x 10(-8) nT(2), while the high-band peak is much lower at P-0 similar to 10(-9) nT(2). The spatial distribution of intensity differs for each emission band implying different source regions and perhaps different source mechanisms.

Plain Language Summary Intense narrow band waves (Z-mode) are observed at Saturn when the spacecraft is located in regions of relatively low density and high magnetic field. These waves are of special importance because they are not seen at such high intensity or over as large a spatial range at Earth. In addition, these waves are known to be very efficient at accelerating electrons under certain conditions and could be responsible for a portion of the observed radiation belts at Saturn. We present an extensive survey of the observations of Z-mode extending over more than 11 years. The survey includes for the first time both the low and high-frequency emissions and orbits from the Cassini final mission, where these waves were seen at a high rate of occurrence. Contour plots and graphs of wave intensity as a function of radius, latitude, and longitude are shown, which will be of value to scientists who model the dynamic processes controlling the electron population at Saturn.