Context: Individual stars in dwarf spheroidal galaxies around the Milky Way Galaxy have been studied both photometrically and spectroscopically. Extremely metal...

We present NLTE abundances of CNO for a sample of four O9 stars in the Galaxy, together with new determinations of their stellar parameters, T_eff, log g...

ζ Oph, HD 149757, is an O9.5 Vnn star with a very high projected rotational velocity (v sin i ≥ 340 km s-1). It is also a classical runaway star due to its high...

We present echelle spectroscopy in the 3500- to 7060-Å range for two positions of the Orion nebula. The data were obtained using the 2.1-m telescope at...

The Sun provides a standard reference against which we compare the chemical abundances found anywhere else in the Universe. Nevertheless, there is not a unique...

Context. The chemical composition of young massive clusters (YMCs) provides stellar population information on their host galaxy. As potential precursors of...

SDSS J082625.70+612515.10 (V = 11.4 [Fe/H] = ‑3.1) and SDSS J134144.60+474128.90 (V = 12.4 [Fe/H] = ‑3.2) were observed with the SDSS 2.5m telescope as part of...

We present a detailed spectroscopic analysis of horizontal branch stars in the globular cluster NGC 3201. We collected optical (4580–5330 Å), high-resolution (...

We present a detailed spectroscopic analysis of RR Lyrae (RRL) variables in the globular cluster NGC 5139 (ω Cen). We collected optical (4580–5330 Å), high...