  Using new data from the UVES spectrograph on the ESO Very Large Telescope and
archive images from the Hubble Space Telescope, we have measured projected
velocity dispersions and structural parameters for two bright young star
clusters in the nearby spiral galaxy NGC 5236. One cluster is located near the
nuclear starburst of NGC 5236, at a projected distance of 440 pc from the
centre, while the other is located in the disk of the galaxy at a projected
galactocentric distance of 2.3 kpc. We estimate virial masses for the two
clusters of (4.2+/-0.7)x10^5 Msun and (5.2+/-0.8)x10^5 Msun and ages (from
broad-band photometry) of 10^(7.1+/-0.2} years and 10^(8.0+/-0.1) years,
respectively. Comparing the observed mass-to-light (M/L) ratios with simple
stellar population models, we find that the data for both clusters are
consistent with a Kroupa-type stellar mass function (MF). In particular, we
rule out any MF with a significantly lower M/L ratio than the Kroupa MF, such
as a Salpeter-like MF truncated at a mass of 1 Msun or higher. These clusters
provide a good illustration of the fact that massive, globular cluster-like
objects ("super star clusters") can form at the present epoch even in the disks
of seemingly normal, undisturbed spiral galaxies.
