CMI growth rates for Saturnian kilometric radiation

We calculate growth rates for extraordinary mode Saturnian kilometric radiation generated by the electron cyclotron maser instability using a ring-type (DGH) electron phase distribution model fitted to measured electron energy distributions in Saturn's auroral acceleration region. The observed distributions are unstable in spatially isolated regions of transverse linear size of order 103 km. Each unstable region has a growth rate consistent with amplification of background radiation to the peak observed intensity, approximately 14 electric field e-foldings. The observed propagation direction and frequency decrement below the electron cyclotron frequency are also consistent with the CMI growth model. Citation: Mutel, R. L., J. D. Menietti, D. A. Gurnett, W. Kurth, P. Schippers, C. Lynch, L. Lamy, C. Arridge, and B. Cecconi (2010), CMI growth rates for Saturnian kilometric radiation, Geophys. Res. Lett., 37, L19105, doi:10.1029/2010GL044940.