CrH molecule: New diagnostic tool for measuring magnetic fields of cool dwarfs

The quantum mechanical calculations for the A⁶Σ⁺ - X⁶Σ⁺ system of the CrH molecule were done in order to obtain its energy level structure and transition strenghts both in the absence and in the presence of a magnetic field. Employing this results and solving a set of the radiative transfer equations, we calculated the Stokes profiles for the entire 0-0 band for different magnetic field strengths and orientations. We show that the CrH lines produce a considerable polarization signal (up to 20%) at 0.5 - 10 kG. Furthermore, the polarization signal shows a significant asymmetry (broad-band polarization) that arises from the Paschen-Back effect in the individual CrH lines. An example of the signal, as it can be observed, is provided.