2021MNRAS.508.3181B

Indications of aluminium monoxide in atmospheres of exoplanets are being reported. Studies using high-resolution spectroscopy should allow a strong detection but require high-accuracy laboratory data. A MARVEL (measured active rotational-vibrational energy levels) analysis is performed for the available spectroscopic data on ²⁷Al¹⁶O: 22 473 validated transitions are used to determine 6485 distinct energy levels. These empirical energy levels are used to provide an improved, spectroscopically accurate version of the ExoMol ATP line list for ²⁷Al¹⁶O; at the same time, the accuracy of the line lists for the isotopically substituted species ²⁶Al¹⁶O, ²⁷Al¹⁷O, and ²⁷Al¹⁸O is improved by correcting levels in line with the corrections used for ²⁷Al¹⁶O. These line lists are available from the ExoMol data base at www.exomol.com.