7 papers · 1 filter
Sulphur abundance in Galactic stars
E. Caffau, P. Bonifacio, R. Faraggiana +3
We investigate sulphur abundance in 74 Galactic stars by using high resolution spectra obtained at ESO VLT and NTT telescopes. For the first time the abundances are derived, where…
Sulphur abundances in Terzan 7
E. Caffau, P. Bonifacio, R. Faraggiana +1
We present here the first measurements of sulphur abundances in extragalactic stars. We make use of high resolution spectra, obtained with UVES at the ESO 8.2 m Kueyen telescope, o…
C,N,O in lambda Boo stars and in composite spectra
R. Faraggiana, P. Bonifacio
The selective abundance of C, N, O (almost solar) with respect to that of other elements (underabundant) in lambda Boo stars has been interpreted as a characteristic peculiarity of…
Lambda Boo stars with composite spectra
R. Faraggiana, P. Bonifacio, E. Caffau +2
We examine the large sample of lambda Boo candidates collected in Table 1 of Gerbaldi et al. (2003) to see how many of them show composite spectra. Of the 132 lambda Boo candidates…
How many lambda Boo stars are binaries ?
Rosanna Faraggiana, Piercarlo Bonifacio
In the attempt to shed new light on the lambda Boo phenomenon we analyzed the astrometric, photometric and spectroscopic characteristics of stars out of a list of recently selected…
Definitions of the Lambda Boo stars
R. Faraggiana, M. Gerbaldi
Since the identification of these stars by Morgan et al. in 1943, various definitions have been proposed for the stars of the Lambda Bootis group. We present here the various defin…