EXPORT: Spectral classification and projected rotational velocities of Vega-type and pre-main sequence stars

In this paper we present the first comprehensive results extracted from the spectroscopic campaigns carried out by the EXPORT (EXoPlanetary Observatio nal Research Team) consortium. During 1998-1999, EXPORT carried out an inte nsive observational effort in the framework of the origin and evolution of protoplanetary systems in order to obtain clues on the evolutionary path fr om the early stages of the pre-main sequence to stars with planets already formed. The spectral types of 70 stars, and the projected rotational veloci ties, v sin i, of 45 stars, mainly Vega-type and pre-main sequence, have be en determined from intermediate- and high-resolution spectroscopy, respecti vely. The first part of the work is of fundamental importance in order to a ccurately place the stars in the HR diagram and determine the evolutionary sequences; the second part provides information on the kinematics and dynam ics of the stars and the evolution of their angular momentum. The advantage of using the same observational configuration and methodology for all the stars is the homogeneity of the set of parameters obtained. Results from pr evious work are revised, leading in some cases to completely new determinat ions of spectral types and projected rotational velocities; for some stars no previous studies were available.