Notes. ^a The uncertainties of the wavenumbers are smaller than 0.000004 cm −1 (~ 0.0013 km s−1). The wavenumbers and uncertainties are computed from the data in supplementary material 6 of Chen et al. (2006), which is also publicly available at https://library.osu.edu/projects/msa/jmsa_06.htm.

b The Einstein A coefficient. The values are retrieved from Table S1 of Yu et al. (2010, supplementary material).

c Additional ν₂ transitions have been detected towards the red hypergiants VY CMa and NML Cyg by Goldhaber (1988) and towards IRC +10216 by Holler (1999; quoted in Monnier et al. 2000b). Schrey (1986) also reported detection of sQ(2, 1) or sQ(2, 2) absorption towards the Mira-type AGB star R Leonis; however, the purported detection had very low S/N ratios in the spectra and the position of the more probable sQ(2, 2) line was too far away from the suspected absorption features.

d Potentially blended with telluric CO₂ R(8) absorption at 967.707233 cm−1.

e Potentially blended with telluric o-H₂O –11_0,11 absorption at 948.262881 cm−1.

References. (1) McLaren & Betz (1980); (2) Goldhaber (1988); (3) Betz & McLaren (1980); (4) Keady & Ridgway (1993); (5) Fonfría et al. (2017); (6) Betz et al. (1979); (7) Monnier et al. (2000c); (8) Monnier et al. (2000b); (9) Betz & Goldhaber (1985).