PDS: The Planetary Atmospheres Node
Cover Page/Proposal Summary
Planetary Atmospheres
Cover Page/Proposal Summary
ROSS-99 NRA 99-OSS-01
Date Due: 5/3/99
|
This proposal shall be used and disclosed for evaluation purposes only, and a copy of this Government notice shall be applied to any reproduction or abstract thereof. Any authorized restrictive notices that the submitter places on this proposal shall also be strictly complied with. Disclosure of this proposal for any reason outside the Government evaluation purposes shall be made only to the extent authorized by the Government. |
| Proposal Type: New Proposal |
| Proposal Category: Laboratory |
| Major Equipment Proposal? No |
| Do you intend to submit an Education/Public Outreach (E/PO) proposal? No |
| Proposal Title: |
| Temperature Dependent Electron Recombination Rates and Spectral Signatures of Ion Reactions Relevant to Titan's Atmosphere |
| Abbreviated Proposal Title: |
| Recombination/Spectra for Titan Atmospheric Models |
| Principal Investigator: |
| Dr. Nigel G.
Adams Dept. of Chemistry University of Georgia Athens, GA 30602 Phone: 706-542-3722 Fax: 706-542-9454 E-mail: adams@sunchem.chem.uga.edu |
| Signature | Date |
| _____________________________________ | ____________ |
| Co-Investigators and Collaborators: | |||
| Type | Name | Affiliation | |
| Sci Co-I | Dr Lucia May Babcock | University of Georgia | babcock@sunchem.chem.uga.edu |
Proposal Summary:
In 2004, Cassini/Huygens will reach Titan probing its atmosphere spectroscopically, mass spectrometrically and by conductivity. To have maximum impact and to suggest measurements that could be made during the restricted observational period, it is critical to model the atmosphere to obtain altitudinal profiles of electron and ion densities, of temperature and the overall spectral emissions. An essential step is to measure the temperature dependence of critical electron-ion recombination coefficients for modeling ionization loss at the appropriate temperatures, and to determine spectral signatures of important reactions to give the overall atmospheric emission. These studies will use a temperature variable flowing afterglow with mass identification of ions, Langmuir probe measurements of electron density and with extensive spectroscopy to obtain spectral signatures of the individual reactions. Systems targeted are recombinations important in recent models at the altitudes Cassini will probe: H2CN+, C2H4+, C2H5+, CH5+, CH3+, CH4+, c-C3H3+ and, to a lesser extent, a variety of CxHy+ and CxHyNz+ ions, such as C3H5+, C5H5+ and H2C3N+. Recombination coefficients will be measured over the relevant temperature range and searches for spectral emissions made from 100-12,000nm (much of Cassini's spectral range). Cluster ions predicted to be important at lower altitudes, H2CN+.N2, H2CN+.C2H2, H3O+.C2H4 will be studied. To complement rate studies of Anicich, spectral emissions for ion-molecule reactions of N2+, CH3+, C2H5+ and H2CN+ variously with CH4, C2H2, H2, C2H6 and HCN will be measured.
