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Updated: Apr 27, 2026
09:40
Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
13.2K
Spectrum of hot methane in astronomical objects using a comprehensive computed line list.
Sergei N Yurchenko1, Jonathan Tennyson2, Jeremy Bailey3
1Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom; and s.yurchenko@ucl.ac.uk.
Summary
A new methane (CH4) line list, 10to10, with nearly 10 billion transitions improves models of exoplanet and brown dwarf atmospheres. This comprehensive dataset is crucial for accurate characterization, especially in the near-infrared.
Area of Science:
- Astrophysics
- Planetary Science
- Spectroscopy
Background:
- Hot methane spectra are vital for understanding environments like flames, cool stars, and exoplanet atmospheres.
- Existing methane spectroscopic data are incomplete, causing underestimations of opacity at short wavelengths and high temperatures.
Purpose of the Study:
- To present a new, comprehensive spectroscopic line list for methane (CH4) named 10to10.
- To provide a dataset applicable to high temperatures (up to 1,500 K) for improved atmospheric modeling.
Main Methods:
- Development of the 10to10 methane line list, incorporating almost 10 billion transitions.
- Application of the 10to10 line list to atmospheric models of celestial objects.
Main Results:
- The 10to10 line list covers a broad spectral range and is valid for temperatures up to 1,500 K.
- Models using 10to10 show improved agreement with observations for the brown dwarf 2MASS 0559-14.
- Studies of the exoplanet HD 189733b using 10to10 revealed up to a 20-fold increase in methane abundance.
Conclusions:
- Accurate characterization of exoplanet and brown dwarf atmospheres requires the inclusion of numerous hot transitions.
- The 10to10 line list is essential for precise atmospheric studies, particularly in the near-infrared spectrum.
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