GTC long-slit spectroscopy of compact stellar clusters in M81
  We here present the ages of four compact stellar clusters (CSCs) in the
nearby spiral galaxy M81, using long-slit optical spectra obtained with the
10.4-m Gran Telescopio Canarias (GTC). All the four CSCs, including the
brightest in this galaxy, are found to have ages between 5 to 6 Myr, with one
of them showing Wolf-Rayet spectral features. The photometric masses of these
clusters, calculated using their spectroscopically-derived ages, lie between
3000 and 18000 Msun. The observed clusters are among the brightest objects, and
hence the most massive, in the entire disk of M81. This implies the absence of
massive (1.0e5 Msun) compact stellar clusters in M81.
