The stellar content of the Hamburg/ESO survey. III. Field horizontal branch stars in the galaxy

Autor(es)

Christlieb, N. ; Beers, Timothy C. ; Thom, C. ; Wilhelm, R. ; Rossi, Silvia ; Flynn, C. ; Wisotzki, L. ; Reimers, D.

• Tipo de documento: Artigo Científico
• Fonte: Astronomy & Astrophysics; v. 431, n. 1, p. 143-148, Feb. 2005.
• Área do conhecimento: Ciências Exatas e da Terra - Astronomia
• Assunto(s): Dinâmica das galáxias Cinemática Estrelas

Resumo

We present a sample of 8321 candidate Field Horizontal-Branch (FHB) stars selected by automatic spectral classification in the digital data base of the Hamburg/ESO objective-prism survey. The stars are distributed over 8225 square degrees of the southern sky, at [b] 30º. The average distance of the sample, assuming that they are all FHB stars, is 9.8 kpc, and distances of up to ~30 kpc are reached. Moderate-resolution spectroscopic follow-up observations and UBV photometry of 125 test sample stars demonstrate that the contamination of the full candidate sample with main-sequence A-type stars is < 16%, while it would be up to 50% in a flux-limited sample at high galactic latitudes. Hence more than ~6800 of our FHB candidates are expected to be genuine FHB stars. The candidates are being used as distance probes for high-velocity clouds and for studies of the structure and kinematics of the Galactic halo. (AU)

• Processo FAPESP: 00/10406-4 - Evolução química e populações estelares da galáxia, nuvens de Magalhães e galáxias elípticas, através de espectroscopia e imageamento
• Beneficiário: Beatriz Leonor Silveira Barbuy
• Modalidade de apoio: Auxílio à Pesquisa - Temático