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Rotation of stars in NGC 6134: a comparison of Delta Scuti stars and non-variable stars

M. B. Rasmussen·H. Bruntt·S. Frandsen·E. Paunzen·H. M. Maitzen
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Abstract

We present results of spectroscopic observations of selected stars in the southern open cluster NGC 6134. We have determined the rotational velocities of the six known Delta Scuti Stars in NGC 6134 as well as several other non-variable stars with similar colour temperature in order to investigate if v sin i and variability is somehow connected: we find no such correlation. We also compare the distribution of v sin i of Delta Scuti Stars and non-variable stars with four other well-studied open clusters to look for any systematic behaviour, but we find no conclusive evidence for v sin i and variability to be connected. We have also used the spectra to carry out an abundance analysis of the Delta Scuti Stars in NGC 6134 to confirm the high metal content of the cluster. We find [Fe/H] = +0.38 +/- 0.05 which is in agreement with the result obtained from Stromgren photometry. We also present Delta-a photometry of the cluster, but we find no chemical peculiar stars based on this index.

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M. B. Rasmussen, H. Bruntt, S. Frandsen, E. Paunzen, H. M. Maitzen. 2002-06-04. Rotation of stars in NGC 6134: a comparison of Delta Scuti stars and non-variable stars. https://doi.org/10.1051/0004-6361%3A20020713

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