DOI: 10.5281/zenodo.7542061
title: Correlated k coefficients for H2-He atmospheres; 30 spectral windows and 1460 pressure-temperature points

description: There are 108 correlated k-coefficients datasets, using the naming convention sonora_2020_fehxxxx_co_yyy.data.196.tar.gz (78 models) or sonora_2020_fehxxxx_co_yyy_noTiOVO.data.196.tar.gz (78 models), where xxxx is the metallicity in 10x dex relative to solar, and yyy is the 100x C/O ratio relative to solar, as a multiplication factor. For example a metallicity of +000 and a C/O ratio of 100 indicates solar abundances, feh+070 should be read as a metallicity of +0.7 dex, feh-100 as -1.0 dex, co_025 should be read as 0.25x C/O relative to solar, and co_200 as 2x C/O relative to solar. We use the Lodders et al. 2010 value for the solar C/O=0.458. The files with “noTiOVO” in the filename contain the correlated k-coefficients calculated without the opacity of TiO and VO. The rest of the molecular abundances and opacities are the same as the equilibrium chemistry values in the regular files. These files are useful for calculating models without any TiO- and VO-induced temperature inversion in the atmosphere.

The correlated-k coefficients are calculated using pre-mixed opacities, with abundances given by equilibrium chemistry for each metallicity-C/O combination, as described in Marley et al. 2021. There are 13 Fe/H values: 0.0, 0.3, 0.5, 0.7, 1.0, 1.3, 1.5, 1.7, 2.0, -0.3, -0.5, -0.7, and -1.0; and 6 C/O values: 0.25, 0.5, 1.0, 1.5, 2.0 and 2.5. The k-coefficients are calculated for a grid of 1460 pressure-temperature points, from10^−6 to 3000 bar and from 75 to 4000 K, listed in the file 1460_layer_list, and can be read in using the IDL script read_k_coefficients.pro. The spectral windows are listed in the file 30_windows.txt (intervals defined as starting at lambda1 and ending at lambda2). NB Please note that for metallicities between 1.3 and 2.0 the value of max_windows has changed from 200 to 1000.

The opacity sources included in the calculations are: C2H2, C2H4, C2H6, CH4, CO, CO2, CrH, Fe, FeH, H2, H3+, H2O, H2S, HCN, LiCl, LiF, LiH, MgH, N2, NH3, OCS, PH3, SiO, TiO, and VO, in addition to alkali metals (Li, Na, K, Rb, Cs). The corresponding high resolution opacities for these atoms and molecules can be found in the Zenodo repository 10.5281/zenodo.6600976. The references for the line lists used in these opacity calculations are listed in the file Opacity_references_2021.pdf. Please include these references, as well as the reference to this Zenodo repository when publishing your paper.

Each dataset contains the following files:

ascii_data: the correlated k coefficients file in ascii format. This can be read by the included IDL code.

binary_data: the correlated k coefficients file in binary format

full_abunds: the relative abundances for all the species from the chemistry files, on the 1460-point pressure-temperature grid

sum_in_atoms: relative abundances for the alkali metals

sum_in_layer: relative abundances for all molecules included in the correlated k-coefficients calculations

Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center.