Abstract:

The design, manufacture and testing of lightweight Carbon Fiber Reinforced Polymer (CFRP) converging spherical mirrors for the RICH-1 Cherenkov detector of LHCb are described. The mirrors have low areal density to minimize the amount of material in the path of traversing particles and need to be fluorocarbon compatible to avoid degradation in the C4F10 radiator gas. The total area is about 2m(2) and high reflectivity (typically 90%) over the wavelength range 200-600nm is required.

Abstract:

We report on studies of 64-channel Multianode Photo-Multiplier Tubes (MaPMTs) as photo-detectors for Ring Imaging CHerenkov (RICH) counters. The newly available 8-dynode stage MaPMT was tested in particle beams at CERN. The MaPMT signals were read out directly with the Beetle1.2 chip which was designed for the LHCb environment and operates at 40 MHz. The photon yield and signal losses were determined for a cluster of 3 × 3 close-packed MaPMTs. The performance of the 8-dynode stage MaPMT was compared to that of the 12-dynode stage MaPMT which has a larger intrinsic gain. © 2006 Elsevier B.V. All rights reserved.

Abstract:

We report on studies of 64-channel Multianode Photo-Multiplier Tubes (MaPMTs) as photo-detectors for Ring Imaging CHerenkov (RICH) counters. The newly available 8-dynode stage MaPMT was tested in particle beams at CERN. The MaPMT signals were read out directly with the Beetle 1.2 chip which was designed for the LHCb environment and operates at 40 MHz. The photon yield and signal losses were determined for a cluster of 3 x 3 close-packed MaPMTs. The performance of the 8-dynode stage MaPMT was compared to that of the 12-dynode stage MaPMT which has a larger intrinsic gain. (c) 2006 Elsevier B.V. All rights reserved.

Abstract:

The LHCb experiment uses a Ring Imaging Cherenkov (RICH) system to provide particle identification over the momentum range 2-10OGeV/c. Two RICH detectors are employed. The upstream detector, RICH 1, utilizes both aerogel and C4F10 gas radiators whilst the downstream RICH 2 uses a CF4 gas radiator. The RICH 2 detector has been fabricated and is installed in the LHCb interaction region; RICH 1 has a programme of phased design and construction. Novel Hybrid Photon Detectors (HPDs) have been developed in collaboration with industry to detect the Cherenkov photons in the wavelength range 200-600 nm. The HPDs are enclosed in iron shielding and Mumetal cylinders to allow operation in magnetic fields up to 50 mT. The performance of pre-series HPDs and the results obtained from a particle test beam using the full LHCb readout chain is presented. The production of a total of 484 HPDs required for the two RICH detectors has recently commenced. The expected performance of the LHCb RICH system, obtained from realistic simulation, is described. (c) 2006 Elsevier B.V. All rights reserved.

Abstract:

The GridPP Collaboration is building a UK computing Grid for particle physics, as part of the international effort towards computing for the Large Hadron Collider. The project, funded by the UK Particle Physics and Astronomy Research Council (PPARC), began in September 2001 and completed its first phase 3 years later. GridPP is a collaboration of approximately 100 researchers in 19 UK university particle physics groups, the Council for the Central Laboratory of the Research Councils and CERN, reflecting the strategic importance of the project. In collaboration with other European and US efforts, the first phase of the project demonstrated the feasibility of developing, deploying and operating a Grid-based computing system to meet the UK needs of the Large Hadron Collider experiments. This note describes the work undertaken to achieve this goal. © 2006 IOP Publishing Ltd.