LHCb RMS-R3, new radiation hard system for on-line monitoring of beam and background conditions in Run 3

Abstract

During Run 3, the LHCb experiment will collect data at a higher luminosity with respect to the previous decade of data taking. The Radiation Monitoring System (RMS-R3), functionally designed for reliable long-run performance, will display the interaction rate of the LHC’s beams along with its background in LHCb. The RMS-R3 comprises 4 detector modules based on the Metal-Foil Detectors radiation hard technology that can withstand fluences up to 1020 MIPs/cm2 or radiation doses of up to a GGy, during its entire lifespan. The modules are placed symmetrically around the beam pipe remarkably close to the interaction point at LHCb at about 2.2 m, while covering a backward acceptance of 7-14 degrees. The readout electronics provide a continuous relative luminosity measurement for LHCb and observations of background evolutions during the various stages of the beam preparation towards collisions. The RMS-R3 detector’s performance has shown good response reproducibility of about 1% and excellent linearity, making it a robust and reliable complementary detector for beam induced background and luminosity measurement at LHCb.