Start with the first course if you don't know what the Wien approximation is. Try the second course if you wonder about solar source functions. Study the third if you need insight on the Lambda operator or NLTE radiative equilibrium. The fourth was intended for IRIS spectrometrists and may cater to optically-thin coronal types.

I assert the moral right to be identified as the author of these
notes. I explicitly permit multiplication and distribution for
non-commercial educational purposes. I appreciate weblinks,
citations, acknowledgements (but not sloppy stealing).
I also appreciate invitations to teach
elsewhere.

- Introduction to Astrophysical Radiative Transfer
- Introduction to Solar Spectrum Formation
- Radiative Transfer in Stellar Atmospheres
- Graphical Introduction to NLTE Chromospheric Line Formation

Rob Rutten 2018-04-19