We present the first results of a survey to obtain Integral Field Spectroscopy of merging galaxies along the Toomre Sequence .
In the present work , we concentrate on the star cluster complexes in the Antennae galaxies ( NGC 4038/39 ) in the overlap region as well as the nuclear region of NGC 4038 .
Using optical spectroscopy we derive the extinction , age , metallicity , velocity , velocity dispersion of the gas and star formation rate for each of the eight complexes detected .
We supplement this study with archival HST-WFPC2 U , B , V , H \alpha , and I band imaging .
Correcting the observed colours of the star clusters within the complexes for extinction , measured through our optical spectra , we compare the clusters with simple stellar population models , with which we find an excellent agreement , and hence proceed to derive the ages and masses of the clusters from comparison with the models .
In five of the complexes we detect strong Wolf-Rayet emission features , indicating young ages ( 3–5 Myr ) .
The ionized gas surrounding the complexes is expanding at speeds of 20 - 40 km/s .
This slow expansion can be understood as a bubble , caused by the stellar winds and supernovae within the complexes , expanding into the remnant of the progenitor giant molecular cloud .
We also find that the complexes themselves are grouped , at about the largest scale of which young star clusters are correlated , representing the largest coherent star forming region .
We show that the area normalized star formation rates of these complexes clearly place them in the regime of star forming regions in starburst galaxies , thereby justifying the label of localized starbursts .
Finally , we estimate the stability of the complexes , and find that they will probably loose a large fraction of their mass to the surrounding environment , although the central regions may merge into a single large star cluster .