Updated line list for the principal isotopologue of carbon monoxide

Abstract

The line list for the principal isotopologue of CO calculated earlier by the present authors (Medvedev, 2022), (Ushakov, 2022) with the irregular dipole-moment function (DMF) is updated with use of the recent high-precision measurements in the 3-0 (Bielska et al., 2022, Hodges et al., 2025) and 7-0 (Balashov et al., 2023) bands. The new data came in contradiction with the experimental data on the 1-0 band (Zou and Varanasi, 2002, Devi et al., 2018). Therefore, we performed fitting several model DMFs to the modified original data set of Meshkov et al. (2022) by including the new above-referenced data and by excluding the data for the 1-0 band. The updated line list is calculated with the irregular DMF. In particular, excellent agreement with recent high-level ab initio calculations on the 3-0 band (Bielska et al., 2022) is emphasized and predictions for the 1-0 and 8-0 bands are outlined. In the new update of the HITRAN database (Gordon et al., 2025) new high-precision measurements in the cold and hot fundamental bands are announced. When these data are published, they will be compared with the predictions of our new line list.