Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-09-11
Astronomy and Astrophysics
Astrophysics
21 pages including 7 figures; submitted to A&A
Scientific paper
10.1051/0004-6361:20000479
High-resolution, high signal-to-noise spectral data are presented for four young B-type stars lying towards the Galactic Centre. Determination of their atmospheric parameters from their absorption line profiles, and uvby photometric measurement of the continua indicate that they are massive objects lying slightly out of the plane, and were probably born in the disk between 2.5-5 kpc from the Centre. We have carried out a detailed absolute and differential line-by-line abundance analyses of the four stars compared to two stars with very similar atmospheric parameters in the solar neighbourhood. The stars appear to be rich in all the well sampled chemical elements (C, N, Si, Mg, S, Al), except for oxygen. Oxygen abundances derived in the atmospheres of these four stars are very similar to that in the solar neighbourhood. If the photospheric composition of these young stars is reflective of the gaseous ISM in the inner Galaxy, then the values derived for the enhanced metals are in excellent agreement with the extrapolation of the Galactic abundance gradients previously derived by Rolleston et al. (2000) and others. However, the data for oxygen suggests that the inner Galaxy may not be richer than normal in this element, and the physical reasons for such a scenario are unclear.
Dufton Philip L.
Keenan Francis P.
Lennon Daniel J.
Rolleston W. R. J.
Smartt Stephen J.
No associations
LandOfFree
Chemical abundances in the inner 5 kpc of the Galactic disk 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 Chemical abundances in the inner 5 kpc of the Galactic disk, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chemical abundances in the inner 5 kpc of the Galactic disk will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-614577