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FUSE Observations of the Post-AGB Star ZNG 1 in the Globular Cluster M5 (NGC 5904)

W. V. Dixon·T. M. Brown·W. B. Landsman
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Abstract

We have observed the hot post-AGB star ZNG 1 in the globular cluster M5 with the Far Ultraviolet Spectroscopic Explorer (FUSE). From the resulting spectrum, we derive an effective temperature T_eff ~ 45,000 K, a rotational velocity v_rot ~ 100 km/s, carbon and nitrogen abundances approximately ten times solar, a wind with terminal velocity near 1000 km/s, and evidence for an expanding shell of material around the star. The carbon and nitrogen enhancements suggest dredge-up of nuclear-processed material on the AGB. The high rotational velocity may reflect a previous merger with a binary companion.

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W. V. Dixon, T. M. Brown, W. B. Landsman. 2002-09-17. FUSE Observations of the Post-AGB Star ZNG 1 in the Globular Cluster M5 (NGC 5904). https://arxiv.org/abs/astro-ph/0209344

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