Physical conditions in CaFe interstellar clouds
Institute of Theoretical Physics and Astrophysics, University of Gdańsk, ul. Wita Stwosza 57, 80-952 Gdańsk, Poland e-mail: firstname.lastname@example.org; email@example.com
Accepted: 25 October 2007
Interstellar clouds that exhibit strong Ca I and Fe I lines are called CaFe clouds. Ionisation equilibrium equations were used to model the column densities of Ca II, Ca I, K I, Na I, Fe I and Ti II in CaFe clouds. We find that the chemical composition of CaFe clouds is solar and that there is no depletion into dust grains. CaFe clouds have high electron densities, ne≈1 cm-3, that lead to high column densities of neutral Ca and Fe.
Key words: ISM: clouds / ISM: abundances / ISM: atoms / ultraviolet: ISM
© ESO, 2007