Observations of the central star and nebula of Abell 65.

Abstract

Imaging and spectrophotometry of the low surface brightness planetary nebula Abell 65 and its eclipsing binary central star are presented. The spectrum of the central star is remarkable in showing H and He lines in emission, similar to the spectra of cataclysmic variables. This is the second PN central star, after HFG 1, to show such stellar line emission. The central star is of high temperature ~80000K and the nebula of high excitation, optically thin, and with a high He abundance. The morphology is unusual with a central dark lane (not dust) and high excitation outer filaments. The relation between the close binary nucleus and the nebular morphology is discussed.