Based on the articles
"C18O, 13CO, and 12CO abundances and excitation temperatures in the Orion B molecular cloud",
by A. Roueff et al.
and "Tracers of the ionization fraction in dense and translucent gas. I. Automated exploitation of massive astrochemical model grids",
by E. Bron et al.
and "Quantitative inference of the H2 column densities from 3mm molecular emission: Case study towards Orion B",
by P. Gratier et al.
Published in Astronomy & Astrophysics, 2020