OH in the diffuse interstellar medium: physical modelling and prospects with upcoming SKA precursor/pathfinder surveys

  title={OH in the diffuse interstellar medium: physical modelling and prospects with upcoming SKA precursor/pathfinder surveys},
  author={S. A. Balashev and Neeraj Gupta and D N Kosenko},
  journal={Monthly Notices of the Royal Astronomical Society},
Hydroxyl ($\rm OH$) is known to form efficiently in cold gas ($T\sim 100$K) along with the molecule $\rm H_2$ and can be used as an efficient tracer of the diffuse molecular gas in the interstellar medium (ISM). Using a simple formalism describing the $\rm H\,I/H_2$ transition and a reduced network of major chemical reactions, we present a semi-analytical prescription to estimate the abundances of O-bearing molecules in the diffuse ISM. We show that predictions based on our prescription are in… 
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