SIMBAD references

The HR-diagram of about 1000 Bp-Ap stars in the solar neighbourhood has been constructed using astrometric data from Hipparcos satellite as well as photometric and radial velocity data. The LM method (Luri 1995, Ph.D. Thesis, Universitat of Barcelona, Luri et al., 1996A&AS..117..405L) allows the use of proper motion and radial velocity data in addition to the trigonometric parallaxes to obtain luminosity calibrations and improved distances estimates. Six types of Bp-Ap stars have been examined: He-rich, He-weak, HgMn, Si, Si+ and SrCrEu. Most Bp-Ap stars lie on the main sequence occupying the whole width of it (about 2mag), just like normal stars in the same range of spectral types. Their kinematic behaviour is typical of thin disk stars younger than about 1Gyr. A few stars found to be high above the galactic plane or to have a high velocity are briefly discussed.