Properties of Mirror Mode Waves observed in the Kronian Magnetosphere

Friday, 19 December 2014
Mario R Rodriguez-Martinez, UNAM National Autonomous University of Mexico, Mexico City, Mexico, Xochitl Blanco-Cano, UNAM, Mexico, Mexico, Christopher T Russell, Univ California, Los Angeles, CA, United States, Ernesto Aguilar-Rodriguez, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico, Robert J Wilson, University of Colorado Boulder, Boulder, CO, United States and Michele Karen Dougherty, Imperial College London, Blackett Laboratory, London, United Kingdom
Mirror Mode Waves (MMW) were observed with Cassini spacecraft in the Kronian middle magnetosphere. They are compressive waves characterized by strong deeps in the magnetic field magnitude and anti-correlated with density. Furthermore, MMW share a common origin with the Ion Cyclotron Waves (ICW), requiring the condition of anisotropy in the plasma temperature (pressure) (T/T>>1). In this work we analyze four Cassini's orbits, with low inclination angle <0.5º, of 2005. The data were obtained from MAG and CAPS instruments. We perform a study about the wave properties and their region of occurrence. We found that the MMW can appear between 6 Rs and 6.9 Rs, with respect to Saturn’s center, indicating that they are further away than ICW. Finally, we use linear kinetic theory, using WHAMP code, in order to determine conditions for wave growth in a plasma resembling the regions where these modes were observed.