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Methane and the Spectra of T Dwarfs

Published online by Cambridge University Press:  26 May 2016

Derek Homeier
Affiliation:
Department of Physics & Astronomy and Center for Simulational Physics, University of Georgia, Athens, GA 30602–2451
Peter H. Hauschildt
Affiliation:
Department of Physics & Astronomy and Center for Simulational Physics, University of Georgia, Athens, GA 30602–2451
France Allard
Affiliation:
CRAL, Ecole Normale Supérieure, Lyon, France

Abstract

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We have updated our PHOENIX model atmospheres and theoretical spectra for ultracool dwarfs with new opacity data for methane based on line strength predictions with the STDS software. By extending the line list to rotational levels of J = 40 we can significantly improve the shape of the near-IR absorption features of CH4, and in addition find an enhanced blanketing effect, resulting in up to 50% more flux emerging in the J band than seen in previous models, which may thus contribute to the brightening in J and blue IR colors observed in T dwarfs.

Type
Part 7. Atmospheres and Internal Structure
Copyright
Copyright © Astronomical Society of the Pacific 2001 

References

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