Abstract details

We have recently obtained optical spectra for a large sample of young and intermediate-age star clusters in several nearby galaxies. The main aim of this programme is to carry out a detailed test of photometric and spectroscopic age- and metallicity indicators, but a first inspection of the data has also revealed emission lines in 3 clusters with ages of 30 Myrs or older. We identify these three objects as likely Planetary Nebula (PN) candidates and discuss their properties. Based on the cluster ages, the progenitor stars had initial masses in the range 3 to 7 Msun, while the PNe central star luminosities and temperatures (estimated from emission line fluxes) are consistent with current masses close to 0.60 Msun. These objects represent a rare opportunity to study PNe whose progenitor stars are known to be of intermediate masses, although detailed analysis is challenging because of the strong underlying stellar continuum from the cluster stars. Detection of 3 PNe in our sample also appears consistent with expectations from stellar evolutionary theory.