Derivation of density and temperature from the Cassini–Huygens CAPS electron spectrometer

Autor: Gethyn R. Lewis, Nicolas André, Andrew J. Coates, Chris S. Arridge, D. R. Linder, Abigail Rymer, L. K. Gilbert
Rok vydání: 2008
Předmět:
Zdroj: Planetary and Space Science. 56:901-912
ISSN: 0032-0633
DOI: 10.1016/j.pss.2007.12.017
Popis: In this paper we present two methods to derive electron fluid parameters from the CAPS–ELS spectrometer on board the Cassini spacecraft currently in orbit around Saturn. In the first part of the paper we give a basic overview of the instrument and describe the challenges inherent in the derivation of density and temperature values using these techniques. We then describe a method to calculate electron moments by integrating the particle distribution function. We also describe a second technique in which we fit the electron energy spectrum with a Gaussian curve and use the peak energy of this curve to derive density and temperature values. We then compare the two methods with particular emphasis on their application to Cassini SOI observations in the saturnian environment and point out the limitations of the two techniques. We will show that results from the two very different methods are in agreement when the physical properties of the environment and of the observed electron populations have been inferred from inspection of the raw data. Finally we will suggest future developments that will remove these limitations.
Databáze: OpenAIRE