Spectrophotometric observations in the optical and near-infrared of six giant H II regions in the high metallicity spiral galaxy M51 are presented. Five of the regions are located in the spiral arms, and the sixth one is very close to the nucleus. These observations and the application of adequate photo-ionization models allow the determination of

Spectrophotometric data of giant H II regions covering the spectral range from λ3600 to 9700 Å in the spiral galaxies M101 and M51 have been analyzed in order to determine reliable chemical abundances and radial gradients. The behaviour of the S/O ratio with metallicity is also explored. The data are consistent, within the errors, with a constant S

We present our observations of several planetary nebulae in the central zones of the spiral galaxy M33. We combine the abundances we derived for our objects with those obtained by Magrini et al. (2004) for a sample of PNe at larger galactocentric distances. We compare the radial abundance distribution derived from planetary nebulae with the one

We present 16600 equivalent widths (EWs) in the spectra of 100 and 94 stars with and without known planets, respectively. We have measured line-by-line EWs of about 80 spectral lines for the refractory elements Si, Ca, Sc, Ti, V, Cr, Mn, Co, Ni. The EWs of about 14 lines of Na, Mg and Al in 53 new comparison spectra have been added to the previous

Atomic data and equivalent widths for 15 red clump giants in 5 open clusters: Cr 110, NGC 2099, NGC 2420, M 67, NGC 7789. (2 data files).

High resolution, high S/N spectra obtained using RETICON and CCD detectors are used to determine the abundances of Al, Si, Ca, Ni and Fe in 23 disc stars in the metallicity range -1.2 ⪉ [Fe/H] ⪉ +0.3. The authors have found overabundances, with respect to iron for Al (≡0.4), Si (≡0.3), and Ca (≡0.2) in stars between -1.2 ⪉ [Fe/H] ⪉ -0.5. The