Language Summary or Abstract: We present a fast multi-level and multi-atom non-LTE radiative transfer method for dynamically evolving stratified atmospheres, such as the solar atmosphere. The preconditioning method of Rybicki & Hummer (RH92) is adopted.

We study broad red-shifted emission in chromospheric and transition region lines that appears to correspond to a form of post-flare coronal rain.

The variation of the vector magnetic field along structures in the solar corona remains unmeasured. 

Observational solar physics is entering a new era with the advent of new 1.5 m class telescopes with adaptive optics, as well as the Daniel K. Inouye 4 m telescope which will become operational in 2019. Major outstanding problems in solar physics all relate to the solar magnetic field.

We consider the observational basis for the belief that flare ribbons in the chromosphere result from energy transport from the overlying corona. We study ribbons of modest flares using magnetic as well as intensity data from the Hinode, SDO and IRIS missions.

We study UV spectra obtained with the SO82-B slit spectrograph on board SKYLAB to estimate the fine structure splitting of the Cl-like 3p43d4D5/2 and 3p43d4D7/2 levels of Fe X.

We study UV spectra obtained with the SO82-B slit spectrograph on board SKYLAB to estimate the fine structure splitting of the Cl-like 3p⁴3d⁴D_5/2 and 3p⁴3d⁴D_7/2 levels of Fe X.