Additional species
As suggested in previous thread, the new spectral files would include the existing species and additional ones.
Existing species: H2O, H2, CO2, CO, CH4, N2, NH3, SO2, H2S, HCN, O3, N2O.
Additional species could be: O2, PO, PN, PH3, PS, CN, HCN, SiH4 (https://arxiv.org/abs/2505.03200), SiO, SiO2, MgO, S2, S8, SH, Fe, Na, K, H- (important opacities in vapourised atmospheres), OCS,(https://www.science.org/doi/full/10.1126/sciadv.adp8105), N2O, CH3Cl, CH3Br, CH3OH, CH3SH, DMS (biosignatures)
Refer to available opacities here:
We should avoid DACE because it cuts the line wings at only 25 cm-1 (see below).
UV cross-sections
Incorporating UV cross-sections is also important. These can be obtained from the website below, and mean that spectral files should extend down to at least 200 nm.
https://www.uv-vis-spectral-atlas-mainz.org/uvvis/
Update continua
Could create these alongside updated continuum and with aerosol properties: #6, #2
There are also new CIA data on the HITRAN website, notably including CH4-CH4 continua that were previously missed.
Line cutting parameters
Currently using 25 cm-1 as the line cutting width, which is the wavenumber distance from line centre at which lines are cut, for tabulating cross-sections. This is too small for H2-dominated scenarios where pressure broadening is important, so we should adopt a wider value of 50 cm-1 or 100 cm-1 if possible. This wider value is what PICASO uses, and leads to substantial differences in optical depth, although makes deriving cross-sections more expensive.
Additional species
As suggested in previous thread, the new spectral files would include the existing species and additional ones.
Existing species: H2O, H2, CO2, CO, CH4, N2, NH3, SO2, H2S, HCN, O3, N2O.
Additional species could be: O2, PO, PN, PH3, PS, CN, HCN, SiH4 (https://arxiv.org/abs/2505.03200), SiO, SiO2, MgO, S2, S8, SH, Fe, Na, K, H- (important opacities in vapourised atmospheres), OCS,(https://www.science.org/doi/full/10.1126/sciadv.adp8105), N2O, CH3Cl, CH3Br, CH3OH, CH3SH, DMS (biosignatures)
Refer to available opacities here:
We should avoid DACE because it cuts the line wings at only 25 cm-1 (see below).
UV cross-sections
Incorporating UV cross-sections is also important. These can be obtained from the website below, and mean that spectral files should extend down to at least 200 nm.
https://www.uv-vis-spectral-atlas-mainz.org/uvvis/
Update continua
Could create these alongside updated continuum and with aerosol properties: #6, #2
There are also new CIA data on the HITRAN website, notably including CH4-CH4 continua that were previously missed.
Line cutting parameters
Currently using 25 cm-1 as the line cutting width, which is the wavenumber distance from line centre at which lines are cut, for tabulating cross-sections. This is too small for H2-dominated scenarios where pressure broadening is important, so we should adopt a wider value of 50 cm-1 or 100 cm-1 if possible. This wider value is what PICASO uses, and leads to substantial differences in optical depth, although makes deriving cross-sections more expensive.