The SPS as injector for LHC: Conceptual design

The last report comprising an overall description of the SPS as an LHC injector was published in 1993. While most of the basic features of the injector scheme have not changed since then, theoretical and experimental studies have been continued and have led to a more complete understanding of the various issues. In addition the decision has now been taken to build the transfer lines from the SPS to the LHC with room-temperature magnets. For this reason a different transfer line had to be chosen for injection into the clockwise circulating LHC ring (Beam 1), with corresponding modifications to the extraction from the SPS. Finally, a more precise planning of the LHC project permits in turn to establish a firm planning and cost profile for the preparation of the SPS as LHC injector. This report describes the present status of the studies, the layout of the major new components of the SPS and their conceptual design.