Heterogeneous chlorine activation on stratospheric aerosols and clouds in the Arctic polar vortex - Wegner, T.; Grooß, J. U.; Hobe, M. von; Stroh, F.; Suminska-Ebersoldt, O.; Volk, C. M.; Hösen, E.; Mitev, V.; Shur, G.; Müller, R. (Atmospheric Chemistry and Physics, 2013)