A HITRAN-formatted UV line list of S_2 containing transitions involving X ^3Σ^-_g, B ^3Σ^-_u, and B” ^3Π_u electronic states

The sulfur dimer (S_2) is an important molecular constituent in cometary atmospheres and volcanic plumes on Jupiter's moon Io. It is also expected to play an important role in the photochemistry of exoplanets. The UV spectrum of S_2 contains transitions between vibronic levels above and below the dissociation limit, giving rise to a distinctive spectral signature. By using spectroscopic information from the literature, and the spectral simulation program PGOPHER, a UV line list of S_2 is provided. This line list includes the primary B ^3Σ^-_u-X ^3Σ^-_g (v'=0-27, v”=0-10) electronic transition, where vibrational bands with v'≥10 are predissociated. Intensities have been calculated from existing experimental and theoretical oscillator strengths, and semi-empirical strengths for the predissociated bands of S_2 have been derived from comparisons with experimental cross-sections. The S_2 line list also includes the B” ^3Π_u-X ^3Σ^-_g (v'=0-19, v”=0-10) vibronic bands due to the strong interaction with the B state. In summary, we present the new HITRAN-formatted S_2 line list and its validation against existing laboratory spectra. The extensive line list covers the spectral range 21700-41300 cm^-1 (∼242-461 nm) and can be used for modeling both absorption and emission.