Published online by Cambridge University Press: 07 August 2017
A comprehensive spectrophotometric survey of the central stars of planetary nebulae with known or suspected binary star nuclei (BSPN) is underway. The aims of this programme are: to determine the nature of the companion to the ionising star of the nebula; to estimate the spectroscopic distance from the spectral type and magnitude of the companion and thence to determine the luminosity of the hot star; to compare the morphologies and excitation/abundance characteristics of BSPN with those of PN produced by single star evolution. The advantage of the distance determined from this simple method is that it is independent of any assumptions about the planetary nebula, in contrast to most other PN distance estimators.
To date 75 percent of known or suspected BSPN have been observed with the 2.5m Isaac Newton Telescope and the 1.5m ESO spectroscopic telescope at low and intermediate dispersions. A selection of preliminary results from the programme is presented, highlighting the binary central stars of NGC 246 and Abell 65.