Results with LHC Beam Instrumentation Prototypes

The beam instrumentation foreseen to provide the necessary diagnostics in the transfer lines and in the main rings of the LHC was conceived in the past years. The requirements expected from the different systems are now being closely analyzed and specified. In a few cases, tests of prototypes have already been performed, profiting from the facilities offered by existing machines. The beam position measurement system had to be tackled first, as the pick-ups had to be integrated into the cryogenic part of the machine. Over the last two years other topics started to be experimentally investigated in order to define the best way to meet the requirements for the LHC era. Amongst these different studies are luminosity monitoring devices, various instruments for the measurement of the transverse beam distributions, the use of head-tail sampling to measure the beam chromaticity and quadrupole gradient modulation to derive the local amplitude of the lattice function. The paper discusses the results of these tests.