Talk abstract details
NGC 5128 - a nearby laboratory for PNe in a giant early-type galaxy
Abstract
NGC 5128 at 3.8 Mpc is the nearest large elliptical galaxy and is ideally suited to a detailed study of its planetary nebular population. About 1100 PNe are known in NGC 5128 and accurate radial velocities of 1050 have been measured with the VLT FLAMES spectrometer, enabling detailed studies of the galaxy kinematic signature. Evidence for PN kinematic sub-groups, perhaps presenting the relics of infalling dwarf galaxies, can be searched, for example.
VLT FORS emission line spectrophotometry and comparison with photoionization models provide light element abundances for the some 40 PNe. A spread in O abundance of about 0.8 dex is found but no obvious radial gradient out to 19 kpc; the mean [O/H] is -0.2. Comparison of the O abundance from the PN with the derived metallicity for the underlying stellar population allows the [O/Fe] ratio, a diagnostic for the enrichment history of the galaxy, to be investigated.
VLT FORS emission line spectrophotometry and comparison with photoionization models provide light element abundances for the some 40 PNe. A spread in O abundance of about 0.8 dex is found but no obvious radial gradient out to 19 kpc; the mean [O/H] is -0.2. Comparison of the O abundance from the PN with the derived metallicity for the underlying stellar population allows the [O/Fe] ratio, a diagnostic for the enrichment history of the galaxy, to be investigated.