A UKST survey of blue objects towards the galactic centre - a search for early-type stars

P.~L. Dufton, S.~J. Smartt, N.~C. Hambly

Research output: Contribution to journalArticlepeer-review

Abstract

We have begun a search for early-type stars towards the galactic centre which are potentially young objects situated within the inner few kiloparsecs of the disk. U and V (or I) band photographic photometry from the UK Schmidt Telescope has been obtained to identify the bluest candidates in nineteen Schmidt fields (centred close to the galactic centre). We have spectroscopically observed these targets for three fields with the FLAIR multi-fibre system to determine their spectral types. In particular, ten early B-type stars have been identified and equivalent width measurements of their Balmer and HeI lines have been used to estimate atmospheric parameters. These early-type objects have magnitudes in the range $11.5\leq V\leq 16.0$, and our best estimates of their distance (given probable highly variable reddening in this direction together with errors in the plate photometry) suggest that some of them originated close to (i.e $R_{\rm g}<3$ kpc), or even beyond the galactic centre. Future high-resolution spectroscopy of these stars will provide reliable atmospheric parameters and element abundances, in order to map the current chemical composition of the inner galaxy.
Original language English 231-244 14 Astronomy and Astrophysics Supplement Series 139 2 https://doi.org/10.1051/aas:1999390 Published - 1 Oct 1999

Keywords

• STARS: EARLY-TYPE, STARS: FUNDAMENTAL PARAMETERS, STARS: IMAGING, GALAXY: CENTER