Cool Stars 14 - Submitted Abstract # 3
This version created on 05 October 2006

Application of Barber-Tennyson synthetic water line list (& ammonia in
prep.) to brown dwarf spectra


Robert Barber, University College London
Jonathan Tennyson, University College London

The BT2 synthetic water line list is the most complete list in
existence, containing 505 million transitions.  It is also the most
accurate.  BT2 has been used in a wide range of astronomical
applications including:  modelling cool stellar atmospheres,
interpreting the spectra of M and L dwarfs, as an indicator of
temperature and column density in the enigmatic object V838 Mon, in
measuring the rotational emperature of comets using non-resonant
fluorescent transitions and their primordial spin temperatures using
the ortho-para ratio.  It has been applied in the identification of
water lines in laboratory flame spectra and in assigning previously
unidentified lines in sunspot spectra.  The talk will focus on brown
dwarf applications for BT2 We have now started to calculated a
synthetic spectrum for ammonia.  This ambitious project has been
prompted by the knowledge that the spectra of ultra-cool dwarfs (and
in particular, the yet to-be observed Y-dwarfs) will include strong
ammonia features.  The talk will detail the background to the ammonia
project, the methodology and the anticipated timescale.  

References:
Jones H.R.A., Pavlenko Y.V., Viti S., Barber R.J.  et al 'Carbon
Monoxide in low-mass dwarf stars', 2005, MNRAS, 358, 105 
Barber R.J.,Tennyson J., Harris G.J., Tolchenov R., 'A high
accuracy computed water line list', 2006, MNRAS, 368, 1087
Lyubchik Y., Jones H.R.A., Pavlenko Y.V., Martin E., 'Making
sense of high resolution near infrared spectra of ultracool
dwarfs.  A&A (submitted)

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