SIMBAD references

Using observations obtained with the Tycho instrument of the ESA Hipparcos satellite, a two-colour photometry is produced for components of more than 7000 Hipparcos double and multiple stars with angular separations 0.1 to 2.5 arcsec. We publish 9473 components of 5173 systems with separations above 0.3 arcsec. The majority of them did not have Tycho photometry in the Hipparcos catalogue. The magnitudes are derived in the Tycho B_T and V_T passbands, similar to the Johnson passbands. Photometrically resolved components of the binaries with statistically significant trigonometric parallaxes can be put on an HR diagram, the majority of them for the first time.