Proton density, nH
Gas density is fixed to this value for isochoric models. This value is not used for isobaric models in which proton density is computed by the code
Unit: cm-3
Scaling factor of the ISRF on the observer side of the cloud.
This radiation field is isotropic whereas a stellar spectrum is modeled as a beam radiation field.
ISRF follows the prescription of Mathis, Mezger, Panagia, 1983, A & A, 128, 212
AVmax
Size of the cloud expressed as a visual extinction
Unit: magnitude