Program: GN-2006A-Q-81

We propose a test to distinguish the two alternative formation scenarios proposed for S0s: (i)S0s are the descendants of spirals whose star-formation ceased via gas-stripping, and (ii)S0s are formed by mergers. Since there is evidence that mergers can induce the formation of globular clusters(GCs), a sensitive test would be to determine whether the last star-formation in S0s was accompanied by the formation of GCs. In the merger scenario, the (luminosity-weighted) ages of the stellar populations of S0s would tell us when the last star-formation(merger) took place, and thus S0s with young stellar populations should also have young GCs. If S0s are fading spirals, their (luminosity-weighted) ages indicate the time when the parent spiral stopped forming stars, and therefore even young S0s should not have young GCs. We propose to determine the ages of the GCs in a S0 with young stellar populations to see whether these galaxies have young GCs.