Assembly and commissioning of the LHC test string

The LHC Project incorporates novel design features which are particularly challenging: twin aperture superconducting magnets with a stored energy higher than 5 MJ per magnet and working in a bath of superfluid helium. It was therefore decided in 1991 to order several full length prototype magnets, and install them in a test string, to demonstrate the feasibility of the LHC. This paper describes the string assembly in its first phase, which consists of a short straight section with its quadrupole and of two dipoles, together with the necessary cryogenics and powering. We then give the first commissioning results as well as future plans