Fast-rotating nearby solar-type stars ^*,**

I. Spectral classification, v sin i, Li abundances and X-ray luminosities

¹ INAF - Catania Astrophysical Observatory, v. S. Sofia 78, 95125 Catania, Italy e-mail: gcutispoto@ct.astro.it
² INAF - Brera Astronomical Observatory, Via Bianchi 46, 22055 Merate (LC), Italy e-mail: pastori@merate.mi.astro.it; gtagliaf@merate.mi.astro.it
³ European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, Germany e-mail: lpasquin@eso.org
⁴ University Federal of Rio Grande do Norte, Department of Physics, 59072-970 Natal, R.N., Brazil e-mail: renan@dfte.ufrn.br
⁵ Astronomical Observatory, NBIfAFG, Juliane Maries Vej 30, 2100 Copenhagen, Denmark e-mail: ja@astro.ku.dk

Corresponding author: G. Cutispoto, gcutispoto@ct.astro.it

Received: 26 October 2001
Accepted: 7 January 2002

Abstract

We present the results of high-resolution spectroscopic and high-precision photometric observations on a sample of 129 late-F and G-type nearby stars selected on the basis of their large rotational velocity. Using also data from the Hipparcos satellite, CORAVEL and from the ROSAT satellite database, we infer spectral types, compute radial velocities, v sin i, Li abundances and X-ray luminosities and investigate the single or binary nature of the sample stars. Such a careful analysis of our sample shows a large fraction of binaries (62%) and of young single disk stars. In particular, at least 9 stars can be considered bona-fide PMS or ZAMS objects, and 30 stars are identified as SBs for the first time. Information on the presence of Ca II K emission and on optical variability is given for some of the stars of the sample.