Rotational velocities of B-type stars from the Edinburgh-Cape survey
نویسندگان
چکیده
The projected rotational velocity distribution for a sample of 34 high Galactic latitude B-type stars from the Edinburgh-Cape Faint Blue Object Survey is presented to investigate the evolutionary status of the group as a whole. Statistical analyses of the distribution show it to be similar to that expected if the sample contained mainly normal Population i early B-type stars, although a contamination of up to 20 % by evolved stars cannot be ruled out. This implies that a large fraction of the sample consists of normal Population i B-type stars similar to those found in the Galactic disk. Possible mechanisms explaining the presence of these stars in the halo are briefly discussed.
منابع مشابه
The Edinburgh – Cape Blue Object Survey – III . Zone 2 ; galactic latitudes − 30 ◦ > b > − 40 ◦
The Edinburgh–Cape Blue Object Survey seeks to identify point sources with an ultraviolet excess. Results for zone 2 of the survey are presented here, covering that part of the South Galactic Cap between 30◦ and 40◦ from the Galactic plane and south of about −12. ◦3 of declination. Edinburgh–Cape zone 2 comprises 66 UK Schmidt Telescope fields covering about 1730 deg2, in which we find some 892...
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