Abundance Determinations in Massive Blue Stars Within the Local Group
Chapter in From Extrasolar Planets to Cosmology: The VLT Opening Symposium, Springer Nature (2000) 331-337
Abundance Gradients Along the Galactic Disk
Chapter in The Evolution of The Milky Way, Springer Nature 255 (2000) 323-334
The Bulge Globular Cluster NGC 6553: Observations with HST's WFPC2, STIS, and NICMOS
(1999)
VLT FORS spectra of blue supergiants in the Local Group galaxy NGC 6822
Astronomy and Astrophysics 352:1 (1999)
Abstract:
Half hour exposures using the ESO VLT/FORS1 combination at Para帽al in Chile have allowed us to obtain spectra for three B supergiants in the dwarf irregular galaxy NGC 6822. The spectra have been analysed using non-LTE techniques and temperatures, gravities, helium content and abundances have been obtained. Overall the metallicity of NGC 6822 is found to lie between that of the LMC and of the SMC, in agreement with previous observations of H II regions and in contrast to the earlier findings of Massey et al. (1995). The analysis of H伪 yields estimates of the mass-loss rates and wind momenta. These results demonstrate that significantly longer exposures with the same instruments will allow us to perform quantitative spectroscopy of blue supergiants in galaxies far beyond the Local Group.On the parallax of WD 0346+246: a halo white dwarf candidate
Monthly Notices of the Royal Astronomical Society 91探花 University Press (OUP) 309:4 (1999) l33-l36