A. Caner

Performance of a prototype of the CMS central detector

A prototype of the barrel Tracking Detector of the Compact Muon Solenoid (CMS) experiment proposed for LHC was built and tested in a beam and in a magnetic field of up to 3 T. It contained six microstrip gas chambers, 25 cm long, and three double-sided silicon microstrip detectors, 12.5 cm long. We report some preliminary results on the performance of the chambers.

Performance of a prototype of the Microstrip Gas Chambers for the CMS experiment at LHC

A set of microstrip gas chamber (MSGC) prototypes, developed for the barrel Tracking Detector of the CMS experiment at LHC, has been tested in a beam. The chambers were 10 cm long, with Pestov or diamond coated glass substrate. The results on the performance of the chambers are reported. The spatial uniformity of the chambers is also illustrated.

High rate tests of microstrip gas chambers for CMS

Abstract MicroStrip Gas Chambers (MSGCs) have been proposed for equipping the outer region of the tracker of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). The MSGCs have undergone extensive development and tests during the last few years and their performance is well established. An important issue that has to be addressed to date is whether MSGCs can maintain their characteristics after a long exposure to an intense flux of particles, similar to LHC. We report results from the most recent beam test addressing this topic.

Test results of heavily irradiated Si detectors

Abstract A large use of silicon microstrip detectors is foreseen for the intermediate part of the CMS tracker. A specific research and development program has been carried out with the aim of finding design layouts and technological solutions for allowing silicon microstrip detectors to be reliably used on a high radiation level environment. As a result of this work single sided, AC-coupled, polysilicon biased, 300xa0μ m thick, p + on n substrate detectors were chosen. Irradiation tests have been performed on prototypes up to fluence 2×10 14 xa0n/cm 2 . The detector performances do not significantly change if the detectors are biased well above the depletion voltage. S / N is reduced by less than 20%, still enough to insure a good efficiency and space resolution. Multiguard structures has been developed in order to reach high voltage operation (above 500xa0V).

THE CMS SILICON MICROSTRIP DETECTORS : RESEARCH AND DEVELOPMENT

Abstract A large quantity of silicon microstrip detectors is foreseen to be used as part of the CMS tracker. A specific research and development program has been carried out with the aim of defining layouts and technological solutions suitable for the use of silicon detectors in high radiation environment. Results presented here summarise this work on many research areas such as techniques for device manufacturing, pre- and post-irradiation electrical characterization, silicon bulk defects analysis and simulations, system performance analytical calculations and simulations and test beam analysis. As a result of this work we have chosen to use single-sided, AC-coupled, poly silicon biased, 300xa0μm thick, p + on n substrate detectors. We feel confident that these devices will match the required performances for the CMS tracker provided they can be operated at bias voltages as high as 500xa0V. Such high-voltage devices have been succesfully manufactured and we are now concentrating our efforts in enhancing yield and reliability.

Performance of the all-silicon CMS tracker

Abstract The Compact Muon Solenoid (CMS) Tracker Collaboration has recently revised the tracking-detector layout. While the previous design relied on Micro Strip Gas Chamber (MSGC) and silicon detectors, the new layout implements solid state sensors as the sole technological choice. The new all-silicon layout is presented and the projected performance is discussed in terms of several benchmark topologies.

THE CMS SILICON TRACKER AT LHC

Abstract The paper describes the Silicon Tracking System of the Compact Muon Solenoid (CMS) experiment that is foreseen to collect events from p–p collision at the E cm =14xa0TeV at the CERN future Large Hadron Collider (LHC). The proposed system consists of four layers of silicon microstrip detectors placed between the two inner layers of the pixel detector and the outer microstrip gas chamber system. The barrel part covers the η region up to 1.8, instrumenting the central radial region between 20 and 50xa0cm. The forward–backward disks extend the coverage up to η =2.6. This paper will review the main characteristics and performances of the system, the actual status of the R&D activities that we are carrying on, and the status of the milestones we have to fulfill in view of the Technical Design Report expected at the end of the year.