Constraining globular cluster formation through studies of young massive clusters – III. A lack of gas and dust in massive stellar clusters in the LMC and SMC

Abstract

Scenarios that invoke multiple episodes of star formation within young globular clusters (GCs) to explain the observed chemical and photometric anomalies in GCs, require that clusters can retain the stellar ejecta of the stars within them and accrete large amounts of gas from their surroundings. Hence, it should be possible to find young massive clusters in the local Universe that contain significant amounts ($>10$\%) of the cluster mass of gas and/or dust within them. Recent theoretical studies have suggested that clusters in the Large Magellanic Cloud (LMC) with masses in excess of $10^4$\msun\, and ages between $30$ and $\sim300$~Myr, should contain such gas reservoirs. We have searched for \hi\ gas within 12 LMC (and 1 SMC) clusters and also for dust using {\em Spitzer} 70\micron\ and 160\micron\ images. No clusters were found to contain gas and/or dust. While two of the clusters have \hi\ at the same (projected) position and velocity, the gas does not appear to be centred on the clusters, but rather part of nearby clouds or filaments, suggesting that the gas and cluster are not directly related. This lack of gas ($<1$\% of the stellar mass) is in strong tension with model predictions, and may be due to higher stellar feedback than has been previously assumed or due to the assumptions used in the previous calculations.