Mining in the Hipparcos raw data

The Hipparcos solutions flagged as unreliable after the completion of the standard data processing have been systematically revisited in the light of additional information, primarily related to their multiplicity. In many cases improved solutions have been obtained, yielding at the same time an Hipparcos based separation and position angle and a better astrometric solution for the system. The principles applied in this reprocessing are explained and more than a hundred new solutions with absolute and relative astrometry are presented and discussed