In addition to the well-known strong temperature sensitivity of molecules, molecular transitions are sensitive to the presence of magnetic fields in sunspots. By comparing synthetic with observed Stokes I and V spectra we test (for the first time in detail) the use of the theory of the molecular Zeeman and Paschen-Back effects for solar and stellar studies. We find that the current theory of the molecular Zeeman effect when combined with spectral synthesis (including as many blending lines as possible) and the best molecular data reproduces the data rather well for both spectral regions considered. These contain two of the best-studied solar molecular bands which are rather different from each other with respect to their Zeeman properties. This opens new perspectives for using molecular lines to investigate cool magnetic features in the solar photosphere and on other stars, including those of later spectral type.
© European Southern Observatory (ESO) 2000
Online publication: January 29, 2001