RADEX
Non-LTE molecular radiative transfer in an isothermal homogeneous medium
This program is free to use for everybody, provided that publications make a reference to our paper: Van der Tak, F.F.S., Black, J.H., Schöier, F.L., Jansen, D.J., van Dishoeck, E.F., 2007, A&A 468, 627-635.

Molecule / Data file

Spectral Range
Minimum frequency (GHz)
Maximum frequency (GHz)

Excitation Conditions
Background temperature (K)
Kinetic temperature (K)
H2 density (cm-3)

Radiative Transfer Parameters
Column density (cm-2)
Line width (km s-1)


If you want to run more extensive calculations, please use the offline version of RADEX.
Click here for the 18-page manual in PDF
Send comments / questions to Floris van der Tak (vdtak @ sron.nl)
Program version: December 2011
Datafile version: January 2016