An accurate, extensive, and practical line list of methane for the HITEMP database. (arXiv:2001.05037v1 [astro-ph.EP])

An accurate, extensive, and practical line list of methane for the HITEMP database. (arXiv:2001.05037v1 [astro-ph.EP])
<a href="http://arxiv.org/find/astro-ph/1/au:+Hargreaves_R/0/1/0/all/0/1">Robert J. Hargreaves</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gordon_I/0/1/0/all/0/1">Iouli E. Gordon</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Rey_M/0/1/0/all/0/1">Michael Rey</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nikitin_A/0/1/0/all/0/1">Andrei V. Nikitin</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tyuterev_V/0/1/0/all/0/1">Vladimir G. Tyuterev</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kochanov_R/0/1/0/all/0/1">Roman V. Kochanov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Rothman_L/0/1/0/all/0/1">Laurence S. Rothman</a>

A methane line list for the HITEMP spectroscopic database, covering 0-13,400
cm$^{-1}$ ($>$746 nm), is presented. To create this compilation, ab initio line
lists of $^{12}$CH$_{4}$ from Rey et al. (2017) ApJ, 847, 105 (provided at
separate temperatures in the TheoReTS information system), are now combined
with HITRAN2016 methane data to produce a single line list suitable for
high-temperature line-by-line calculations up to 2000 K. An
effective-temperature interpolation model was created in order to represent
continuum-like features at any temperature of interest. This model is
advantageous to previously-used approaches that employ so-called
“super-lines”, which are suitable only at a given temperature and require
separate line lists for different temperatures. The resultant HITEMP line list
contains $sim$32 million lines and is significantly more flexible than
alternative line lists of methane, while accuracy required for astrophysical or
combustion applications is retained. Comparisons against experimental
observations of methane absorption at high temperatures have been used to
demonstrate the accuracy of the new work. The line list includes both strong
lines and quasi-continuum features and is provided in the common user-friendly
HITRAN/HITEMP format, making it the most practical methane line list for
radiative transfer modeling at high-temperature conditions.

A methane line list for the HITEMP spectroscopic database, covering 0-13,400
cm$^{-1}$ ($>$746 nm), is presented. To create this compilation, ab initio line
lists of $^{12}$CH$_{4}$ from Rey et al. (2017) ApJ, 847, 105 (provided at
separate temperatures in the TheoReTS information system), are now combined
with HITRAN2016 methane data to produce a single line list suitable for
high-temperature line-by-line calculations up to 2000 K. An
effective-temperature interpolation model was created in order to represent
continuum-like features at any temperature of interest. This model is
advantageous to previously-used approaches that employ so-called
“super-lines”, which are suitable only at a given temperature and require
separate line lists for different temperatures. The resultant HITEMP line list
contains $sim$32 million lines and is significantly more flexible than
alternative line lists of methane, while accuracy required for astrophysical or
combustion applications is retained. Comparisons against experimental
observations of methane absorption at high temperatures have been used to
demonstrate the accuracy of the new work. The line list includes both strong
lines and quasi-continuum features and is provided in the common user-friendly
HITRAN/HITEMP format, making it the most practical methane line list for
radiative transfer modeling at high-temperature conditions.

http://arxiv.org/icons/sfx.gif