  The high cosmic abundance and the intermediate volatility and chemical
properties of sulfur allow the use of sulfur-bearing species as a tracer of the
chemical processes in the atmospheres of hot Jupiter exoplanets. Nevertheless,
despite its properties and relevance as a tracer of the giant planets'
formation history, little attention has been paid to this species in the
context of hot Jupiter atmospheres. Here we provide an overview of the
abundances of sulfur-bearing species in hot Jupiter atmospheres under different
conditions and explore their observability. We use the photochemical kinetics
code VULCAN to model hot Jupiter atmospheric disequilibrium chemistry.
Transmission spectra for these atmospheres are created using the modelling
framework ARCiS. We vary model parameters such as the diffusion coefficient,
and we study the importance of photochemistry on the resulting mixing ratios.
Furthermore, we vary the chemical composition of the atmosphere by increasing
the metallicity from solar to ~10 times solar. We also explore different C/O
ratios. We find that H2S and SO2 are the best candidates for detection between
1 and 10 micron, using a spectral resolution that is representative of the
instruments on board the JWST. H2S is easiest to detect at an equilibrium
temperature of ~1500 K and C/O ratios between 0.7 and 0.9, with the ideal value
increasing slightly for increasing metallicity. SO2 is most likely to be
detected at an equilibrium temperature of ~1000 K at low C/O ratios and high
metallicities. Nevertheless, among these two molecules, we expect SO2 detection
to be more common, as it is detectable in scenarios more favoured by formation
models. We conclude that H2S and SO2 will most likely be detected in the coming
years with the JWST and that the detection of these species will provide
information on atmospheric processes and planet formation scenarios.
