  Yan and Lazarian have proposed a new technique through which the magnetic
field geometry in the diffuse interstellar medium, or in circumstellar matter,
could be determined from the linear polarization of interstellar absorption or
fluorescence emission lines from ions pumped by an anisotropic illuminating
flux. New long-slit spectroscopic observations of the reflection nebula
NGC2023, obtained with the Southern African Large Telescope Robert Stobie
Spectrograph (RSS), have detected a number of atomic fluorescence lines of OI,
NI, SiII, and FeII for the first time in a neutral medium. A model which
predicts these lines and others illustrates which lines would be appropriate
targets for an RSS spectropolarimetric investigation of this new diagnostic.
