Distances for Galactic planetary nebulae - II. A southern hemisphere survey

Abstract

We present integrated [O II] 3726, 3729-A and [S II] 6716, 6731-A doublet ratios and electron densities for 63 southern Galactic planetary nebulae (PN). We find that the densities derived from the integrated [O II] and [S II] doublet ratios are in excellent agreement with each other. We have derived distances to 57 of these objects, using recent calibrations based on observations of Magellanic Cloud PN. To derive distances to PN which are optically thin in the Lyman continuum, we use a variation on the Shklovsky constant ionized mass method which requires the electron density from the mean [O II] doublet ratios only and requires no knowledge of the nebular filling factor or angular diameter