  Coronal mass ejections (CMEs) are explosive events that occur basically daily
on the Sun. It is thought that these events play a crucial role in the angular
momentum and mass loss of late-type stars, and also shape the environment in
which planets form and live. Stellar CMEs can be detected in optical spectra in
the Balmer lines, especially in Halpha, as blue-shifted extra
emission/absorption. To increase the detection probability one can monitor
young open clusters, in which the stars are due to their youth still rapid
rotators, and thus magnetically active and likely to exhibit a large number of
CMEs. Using ESO facilities and the Nordic Optical Telescope we have obtained
time series of multi-object spectroscopic observations of late-type stars in
six open clusters with ages ranging from 15 Myrs to 300 Myrs. Additionally, we
have studied archival data of numerous active stars. These observations will
allow us to obtain information on the occurrence rate of CMEs in late-type
stars with different ages and spectral types. Here we report on the preliminary
outcome of our studies.
