Near-Infrared Spectroscopy of Simple Hydrocarbons and Carbon Oxides Diluted in Solid N_2 and as Pure Ices: Implications for Triton and Pluto

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

80

Scientific paper

In this paper are presented near-infrared laboratory spectra of pure ices of CH_4, C_2H_4, C_2H_6, CO, and CO_2, as well as a systematic study of changes in their spectral behavior when isolated in a matrix of nitrogen ice. These studies were prompted by recent low-noise and high-spectral-resolution infrared observations of the surfaces of Triton and Pluto (e.g., D. P. Cruikshank et al., 1993, Science 261, 742-745 T. C. Owen et al., Science 261, 745-748). The data in this paper permit a sophisticated analysis of the published Pluto and Triton spectra, and will be useful in interpreting future observations as well. Two different techniques were employed for preparing our ice samples: (1) condensation of thin films on a cold window, and (2) growth of crystals from the liquid phase in a closed cryogenic cell. An important result we obtained is that spectra strongly depend on the technique used. With a closed cell, samples are formed under conditions of thermodynamical equilibrium and experiments are perfectly reproducible. Additionally, the samples formed from mixtures of N_2 and CH_4, in the closed cell, show characteristics consistent with the N_2:CH_4 phase diagram obtained by A. I. Prokhvatilov and L. D. Yantsevich (1982, Sov. J. Low Temp. Phys. 9, 94-98). On the other hand, it appeared that this is not at all the case with thin films. Assuming that the surfaces of Triton and Pluto are in thermodynamical equilibrium, the closed cell technique is more appropriate. Finally, the measurements conducted with different closed cryogenic cells show that the peak frequencies of the bands of the CH_4 molecule isolated in solid N_2 are shifted with respect to pure CH_4 ice and are also dependent on the temperature and crystal phase of solid N_2 (alpha vs beta). These dependencies have been precisely measured, and it is shown how they could be used to determine the CH_4 dilution state and the temperature at the surfaces of Triton and Pluto to higher precision than has been previously achieved.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Near-Infrared Spectroscopy of Simple Hydrocarbons and Carbon Oxides Diluted in Solid N_2 and as Pure Ices: Implications for Triton and Pluto does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Near-Infrared Spectroscopy of Simple Hydrocarbons and Carbon Oxides Diluted in Solid N_2 and as Pure Ices: Implications for Triton and Pluto, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Near-Infrared Spectroscopy of Simple Hydrocarbons and Carbon Oxides Diluted in Solid N_2 and as Pure Ices: Implications for Triton and Pluto will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1474808

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.