Two nitrogen rich main sequence B-stars in the Small Magellanic Cloud cluster, NGC 330.

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

31

Magellanic Clouds, Stars: Early-Type, Stars: Abundances, Stars: Evolution, Globular Clusters: Individual: Ngc 330 (Smc)

Scientific paper

High resolution spectra of two narrow lined main-sequence B-type stars in the SMC cluster NGC 330 are analysed using LTE methods to obtain their chemical compositions relative to SMC and galactic field B-stars. It is found that these stars, designated A01 and B04, have parameters ({T_eff_, logg}) of {26000, 3.8} and {23000, 3.6} respectively and, surprisingly, nitrogen abundances approximately 0.8dex higher than other SMC main-sequence B-stars. There is also marginal evidence for moderate deficiencies of both oxygen and silicon consistent with the previously reported low metallicity of this cluster. Since supergiants in the cluster do not exhibit such a large nitrogen enrichment it is argued that A01 and B04 have had their surface chemical compositions modified either as the result of binary mass transfer or due to rotationally induced turbulent diffusion. For both scenarios the absence of a complementary carbon deficiency is surprising. These findings, combined with previous observations of the most luminous main-sequence stars in the cluster, imply that the upper main-sequence of the cluster is difficult to understand in terms of standard stellar evolution models.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Two nitrogen rich main sequence B-stars in the Small Magellanic Cloud cluster, NGC 330. does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Two nitrogen rich main sequence B-stars in the Small Magellanic Cloud cluster, NGC 330., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Two nitrogen rich main sequence B-stars in the Small Magellanic Cloud cluster, NGC 330. will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1210831

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.