arXiv 0809.03272008-09-01astro-ph

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

备注：: 6 pages + 5 figures, accepted for publication in MNRAS
DOI：: 10.1111/j.1365-2966.2008.13899.x

英文摘要：

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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