Pristine CNO abundances from Magellanic Cloud B stars II. Fast rotators in the LMC cluster NGC 2004

Abstract

We present spectroscopic abundance analyses of three main-sequence B stars in the young Large Magellanic Cloud cluster NGC 2004. All three targets have projected rotational velocities around 130 km/s. Techniques are presented that allow the derivation of stellar parameters and chemical abundances in spite of these high v sin i values. Together with previous analyses of stars in this cluster, we find no evidence among the main-sequence stars for effects due to rotational mixing up to v sin i around 130 km/s. Unless the equatorial rotational velocities are significantly larger than the v sin i values, this finding is probably in line with theoretical expectations. NGC 2004/B30, a star of uncertain evolutionary status located in the Blue Hertzsprung Gap, clearly shows signs of mixing in its atmosphere. To verify the effects due to rotational mixing will therefore require homogeneous analysis of statistically significant samples of low-metallicity main-sequence B stars over a wide range of rotational velocities.

arXiv comment12 pages, 5 figures, 2 tables; accepted for publication in ApJ (vol. 633, p. 899)

References in corpus (9)

• Stellar evolution with rotation VII: Low metallicity models and the blue to red supergiant ratio in the SMC
• Chemical Evolution of the Magellanic Clouds: analytical models
• A-type Supergiant Abundances in the SMC: Probes of Evolution
• The VLT-FLAMES Survey of Massive Stars: Observations in the Galactic Clusters NGC 3293, NGC 4755 and NGC 6611
• Chemical Abundances in Twelve Red Giants of the Large Magellanic Cloud from High-Resolution Infrared Spectroscopy
• Pristine CNO abundances from Magellanic Cloud B stars I. The LMC cluster NGC 2004 with UVES
• Rotation of Early B-type Stars in the Large Magellanic Cloud - The role of evolution and metallicity
• Chemical Abundances of OB Stars with High Projected Rotational Velocities
• More nitrogen rich B-type stars in the SMC cluster, NGC 330

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