The Geometry of the LHC Main Dipole

The main lines of discussion and analysis for the LHC dipole geometry are related to the shape of the cold mass at different stages of production and tests. The limitations in the stability of the cold mass shape induces constraints for the positioning of the spool pieces (feed down effects), for the flanges (interconnectivity) and the overall shape (aperture considerations). The geometry after acceptance in industry may change by the time of measurements at CERN. Tolerances that are needed by hardware and by beam physics will be reviewed.