X-RAY AND EUV EMISSION-SPECTRA OF OXYGEN IONS PRECIPITATING INTO THE JOVIAN ATMOSPHERE

Spectra of soft X ray and EUV emissions of oxygen ions, precipitating into the Jovian atmosphere, are calculated, taking into account the dy namical evolution of the energy and charge distributions of the ions a s they propagate. Monte Carlo simulations are performed using experime ntal and theoretical cross sections of ion collisions with the atmosph eric gases. The numbers of X ray and EUV photons produced per precipit ating oxygen ion are calculated as functions of the initial ion energy and charge. The energy and charge distribution functions are used to evaluate the intensities of characteristic X ray and EUV emission line s of oxygen ions in Jovian auroras. Radiative cascade transitions from highly excited ion states are shown to be an important source mechani sm of soft X ray and ultraviolet emission Lines.