Reply to comment by B. Cecconi on "Spectral features of SKR observed by Cassini/RPWS: Frequency bandwidth, flux density and polarization"

Abstract

International audienceThe main purpose of the paper by Galopeau et al.[2007] was to classify the spectral features of the Saturniankilometric radiation (SKR) starting from three physicalobserved parameters: the frequency bandwidth, the fluxdensity, and the pol arization. We show in the presentresponse that an unsupervised application of arbitrary auto-matic criteria during the data processing (such as a signal-to-noise ratio greater than 23 dB) can totally judge a weaknatural emission as a background noise. As a consequence,such a situation may lead to consideration of only the datapresenting a degree of circular polarization close to 100%and neglect a huge part of the data. Galopeau et al. [2007]considered a phenomenological aspect and gave an estima-tion of the Stokes parameters. This approach leads to firstrecognizing spectral components (flux density and band-width) in the frequency range from 3.5 kHz to 1200 kHz,and then deriving the Stokes parameters for each compo-nent. The Cassini/RPWS instrument provides long-lastingcoverage of radio emissions at Saturn with unprecedentedinstrumental capabilities