SIMBAD references

We report on high-resolution optical time series spectroscopy of the central star of the `Eskimo' planetary nebula NGC 2392. Data sets were secured with the European Southern Observatory (ESO) 2.3 m in 2006 March and Canada-France-Hawaii Telescope (CFHT) 3.6 m in 2010 March to diagnose the fast wind and photospheric properties of the central star. The Hei and Heii recombination lines reveal evidence for clumping and temporal structures in the fast wind that are erratically variable on time-scales down to ∼ 30 min (i.e. comparable to the characteristic wind flow time). We highlight changes in the overall morphology of the wind lines that cannot plausibly be explained by line-synthesis model predictions with a spherically homogeneous wind. Additionally, we present evidence that the ultravoilet line profile morphologies support the notion of a high-speed, high-ionization polar wind in NGC 2392. Analyses of deep-seated, near-photospheric absorption lines reveals evidence for low-amplitude radial velocity shifts. Fourier analysis points tentatively to an ∼ 0.12-d modulation in the radial velocities, independently evident in the ESO and CFHT data. We conclude that the overall spectroscopic properties support the notion of a (high-inclination) binary nucleus in NGC 2392 and an asymmetric fast wind.