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arXiv · 0809.0327

AAOmega radial velocities rule out current membership of the planetary nebula NGC 2438 in the open cluster M46

L. L. Kiss·Gy. M. Szabo·Z. Balog·Q. A. Parker·D. J. Frew
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Abstract

We present new radial velocity measurements of 586 stars in a one-degree field centered on the open cluster M46, and the planetary nebula NGC 2438 located within a nuclear radius of the cluster. The data are based on medium-resolution optical and near-infrared spectra taken with the AAOmega spectrograph on the Anglo-Australian Telescope. We find a velocity difference of about 30 km/s between the cluster and the nebula, thus removing all ambiguities about the cluster membership of the planetary nebula caused by contradicting results in the literature. The line-of-sight velocity dispersion of the cluster is 3.9+/-0.3 km/s, likely to be affected by a significant population of binary stars.

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L. L. Kiss, Gy. M. Szabo, Z. Balog, Q. A. Parker, D. J. Frew. 2008-09-01. AAOmega radial velocities rule out current membership of the planetary nebula NGC 2438 in the open cluster M46. https://doi.org/10.1111/j.1365-2966.2008.13899.x

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