[Previous] | [Session 37] | [Next]
J. -C. G\'erard, V. Dols, D. Colignon, D. Grodent (LPAP-ULg), J. T. Clarke (SPRL-Michigan), J. H. Waite, G. R. Gladstone (SwRI)
The Jovian aurora exhibits bright emissions mainly due the bright Lyman-alpha line and to radiation from excited singlet states to the ground electronic state extending from 800 to 1600~Å. Above 1200~Å, the molecular spectrum is dominated by the Lyman (B-X)~bands and continuum and the Werner (C-X)~bands. These transitions have been observed with the Goddard High Resolution Spectrometer (GHRS) and the Space Telescope Imaging Spectrometer (STIS) at various spectral and spatial resolutions. To analyze these spectra, a model synthetic auroral spectrum has been constructed and applied to the analysis of the ro-vibrational temperature of H2 and a search for non-H2 emission features. It has been recently updated to include the latest singlet state excitation and cascading cross sections, self-absorption in optically thick lines and to account for the energy distribution of the secondary electrons which cause additional excitation. We illustrate these effects in a few study cases and apply the model to high resolution (0.5~Å) GHRS spectra and low resolution STIS spectra of the entire H2 spectrum at wavelengths longer than Lyman-alpha. We determine the methane column overlying the auroral emission peak and find that a better fit is obtained with additional absorption by acetylene.
If you would like more information about this abstract, please follow the link to http://www.astro.ulg.ac.be/orientation/lpape.html. This link was provided by the author. When you follow it, you will leave the Web site for this meeting; to return, you should use the Back comand on your browser.
The author(s) of this abstract have provided an email address for comments about the abstract: gerard@astro.ulg.ac.be