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Interstrip and backplane capacitances on silicon microstrip detectors with p+ strip on n substrate of 320μm thickness were measured for pitches between 60 and 240μm and width over pitch ratios between 0.13 and 0.5. Parametrisations of capacitance w.r.t. pitch and width were compared with data. The detectors were measured before and after being irradiated to a fluence of 4×1014protons/cm2 of 24GeV/c momentum. The effect of the crystal orientation of the silicon has been found to have a relevant influence on the surface radiation damage, favouring the choice of a 〈100〉 substrate. Working at high bias (up to 500 V in CMS) might be critical for the stability of detector, for a small width over pitch ratio. The influence of having a metal strip larger than the p+ implant has been studied and found to enhance the stability.

We report the results of two beam tests performed in July and September 1995 at CERN using silicon microstrip detectors of various types: single sided, double sided with small angle stereo strips, double sided with orthogonal strips, double sided with pads. For the read-out electronics use was made of Preshape32, Premux128 and VA1 chips. The signal to noise ratio and the resolution of the detectors was studied for different incident angles of the incoming particles and for different values of the detector bias voltage. The goal of these tests was to check and improve the performances of the prototypes for the CMS Central Detector.

Abstract A comparison between silicon microstrip detectors with the same geometry built on 〈1 0 0〉 and 〈1 1 1〉 substrates have been carried out. Three sets of structures— 〈1 0 0〉 low resistivity, 〈1 1 1〉 low resistivity and 〈1 1 1〉 high resistivity—have been electrically characterized. Leakage current, depletion voltage, interstrip capacitance and resistance have been measured before and after neutron irradiation. The samples have been irradiated at five different fluences, up to ≃1.5×10 14 n / cm 2 . The measurements show that the leakage current does not depend, at a given fluence, on crystal orientation and on silicon resistivity. At high irradiation fluences the interstrip resistance decreases for all structures to few tens MΩ . The low resistivity substrates, after type inversion, have a lower depletion voltage than the high resistivity ones. The interstrip capacitance is much less sensitive to radiation effects in 〈1 0 0〉 than in 〈1 1 1〉 structures. We conclude that 〈1 0 0〉 low resistivity sensors show, after irradiation, better performances with respect to standard 〈1 1 1〉 high resistivity devices.

We present results obtained with full-size wedge silicon microstrip detectors bonded to APV6 (Raymond et al., Proceedings of the 3rd Workshop on Electronics for LHC Experiments, CERN/LHCC/97-60) readout chips. We used two identical modules, each consisting of two crystals bonded together. One module was irradiated with 1.7×1014neutrons/cm2. The detectors have been characterized both in the laboratory and by exposing them to a beam of minimum ionizing particles. The results obtained are a good starting point for the evaluation of the performance of the “ensemble” detector plus readout chip in a version very similar to the final production one. We detected the signal from minimum ionizing particles with a signal-to-noise ratio ranging from 9.3 for the irradiated detector up to 20.5 for the non-irradiated detector, provided the parameters of the readout chips are carefully tuned.

A proposal for a pixel-based Level 1 trigger for the Super-LHC is presented. The trigger is based on fast track reconstruction using the full pixel granularity exploiting a readout which connects different layers in specific trigger towers. The trigger will implement the current CMS high level trigger functionality in a novel concept of intelligent detector. A possible layout is discussed and implications on data links are evaluated.

Like its subject matter, the production of this book has been an eminently collective and participatory process.My debts-personal, intellectual, and professional-are many and deep.These debts begin in UC Berkeley's Sociology department, which provided an extraordinary intellectual community during my years of graduate study.For me and many others Michael Burawoy stands at the center of this community, not only because of his brilliance and charisma, but above all for his ability to forge col-

This paper describes the main achievements in the development of radiation resistant silicon detectors to be used in the CMS tracker. After a general description of the basic requirements for the operation of large semiconductor systems in the LHC environment, the issue of radiation resistance is discussed in detail. Advantages and disadvantages of the different technological options are presented for comparison. Laboratory measurements and test beam data are used to check the performance of several series of prototypes fabricated by different companies. The expected performance of the final detector modules are presented together with preliminary test beam results on system prototypes.

We present the beam test results of single-sided silicon microstrip detectors, with different substrate resistivities. The effects of radiation damage are studied for a detector irradiated to a fluence of 2.4×1014n/cm2. The detectors are read out with the APV6 chip, which is compatible with the 40MHz LHC clock. The performance of different detectors and readout modes are studied in terms of signal-to-noise ratio and efficiency.

Monte Carlo production for the CMS experiment is carried out in a distributed computing environment; the goal of producing 30M simulated events per month in the first half of 2007 has been reached. A brief overview of the production operations and statistics is presented.

Monte Carlo production in CMS has received a major boost in performance and scale since the past CHEP06 conference. The production system has been re-engineered in order to incorporate the experience gained in running the previous system and to integrate production with the new CMS event data model, data management system and data processing framework. The system is interfaced to the two major computing Grids used by CMS, the LHC Computing Grid (LCG) and the Open Science Grid (OSG).

The CMS experiment at the LHC will comprise a large silicon strip tracker. This article highlights some of the results obtained in the R&D studies for the optimization of its silicon sensors. Measurements of the capacitances and of the high voltage stability of the devices are presented before and after irradiation to the dose expected after the full lifetime of the tracker.

A comparative study on silicon microstrip detectors of the same geometry built on 〈100〉 low resistivity and 〈111〉 high resistivity substrates has been carried out. Leakage current, depletion voltage and interstrip capacitance have been measured before and after irradiation with 34 MeV protons at regular intervals during the beneficial annealing period. The samples were irradiated at four different fluences up to ≃2×1014n/cm2. The measurements after irradiation show that leakage current does not depend on substrate resistivity and crystal orientation. Above type inversion also, the depletion voltage does not depend substantially on the initial resistivity. The interstrip capacitance is damaged both for 〈100〉 and 〈111〉 silicon substrates, even if in the first case the interstrip capacitance increase is lower, as expected from the known difference in charge trapping effects. The results of this work are compared with previous measurements performed on identical structures irradiated with neutrons.

The behaviour of the leakage current, interstrip resistance and capacitance have been studied on silicon microstrip detectors during an annealing period equivalent to ≃108min at room temperature, after 34MeV proton irradiation. A comparison between samples of the same geometry built on 〈100〉 and 〈111〉 substrates with different resistivity has been carried out. The samples were irradiated at 4 different fluences up to 1×1014p/cm2. After the irradiation the measurements were performed at room temperature and after heating the samples at 60°C, 80°C and 120°C to cover the complete annealing curve. The leakage current shows the same annealing behaviour typical of a simple diode. The interstrip resistance measured at full depletion voltage (Vdep) decreases in all structures, going down to few tens of MΩ at the highest fluence. It remains practically constant during the annealing period. The interstrip capacitance (at Vdep) varies during the annealing period with the same behaviour in both substrates and for all the fluence values: it decreases during the annealing at room temperature, reaching a minimum value, and increases after each heat treatment. Bistable defects seem to contribute to the interstrip capacitance variation.

Abstract The behaviour of leakage current and depletion voltage have been studied on silicon diodes of different resistivity during the full annealing period after 34 MeV proton irradiation. After the irradiation the measurements were performed after heating the samples to cover the complete annealing curve. The hardness factor was estimated through the measurement of the diode leakage current as a function of annealing time. The diode leakage current and depletion voltage values show a significant decrease as a function of time after heating at high temperatures. This effect is typical of bistable defects. The defect can be activated by illumination, forward bias and further heating. The average time constant of the de-activation process has been found to be 4 h , independently of the activation process.

Capacitance, resistance and current measurements were carried out on single-sided, n+ on n silicon strip detectors. We studied the type inversion after irradiating the detectors with neutron fluences up to 8.3×1013neutron/cm2. To understand the macroscopic irradiation effects, a SPICE model of the detector was developed. Simulating the capacitance measurements, we were able to reproduce the measured frequency dependence of the relevant capacitances, both for non-irradiated and for irradiated detectors.

The silicon strip tracker (SST) is a key element of the CMS Tracking System. It consists of five cylindrical layers and of six mini-disks of microstrip-silicon sensors in the barrel region and of ten disks per side in the forward region; an SST overview is given. After a brief introduction on the general tracking requirements in terms of momentum resolution, tracking efficiency and vertex capability, we discuss the physical requirements and experimental constraints for the SST. The basic functional sub-unit of the system, the module, together with its active elements, the sensors, are also described.

The CMS Silicon tracker consists of 70m2 of microstrip sensors which design will be finalized at the end of 1999 on the basis of systematic studies of device characteristics as function of the most important parameters. A fundamental constraint comes from the fact that the detector has to be operated in a very hostile radiation environment with full efficiency. We present an overview of the current results and prospects for converging on a final set of parameters for the silicon tracker sensors.

For the construction of the silicon microstrip detectors for the Tracker of the CMS experiment, two different substrate choices were investigated: A high-resistivity (6 k cm) substrate with (111) crystalorientation and a low-resistivity (2k cm) one with (100) crystalorientation. The interstrip and backplane capacitances were measured before and after the exposure to radiation in a range of strip pitches from 60 μm to 240 μm and for values of the width-over-pitch ratio between 0.1 and 0.5.

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, 300 μm 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 500 V. Such high-voltage devices have been succesfully manufactured and we are now concentrating our efforts in enhancing yield and reliability.

The breakdown performance of CMS barrelmodule prototype detectors and test devices with single and multi-guard structures were studied before and after neutron irradiation up to 2·1014 1 MeV equivalent neutrons. Before irradiation avalanche breakdown occurred at the guard ring implant edges. We measured 100–300 V higher breakdown voltage values for the devices with multi-guard than for devices with single-guard ring. After irradiation and type inversion the breakdown was smoother than before irradiation and the breakdown voltage value increased to 500–600 V for most of the devices.

Illness as Many Narratives is about the many narratives of illness, but the development of the ideas and the process of writing it contain a multitude of other narratives and encounters too.First and foremost, I owe a great debt to the anonymous reviewers for their insights and direction as the project was taking shape and to Jackie Jones, as well as to the editorial team, at Edinburgh University Press for their support at different stages.The book has been enriched by conversations with, and inspiration from, a number of friends, colleagues and scholars of illness narratives, medical humanities and disability studies over many years.

This paper describes the Silicon microstrip Tracker of the CMS experiment at LHC. It consists of a barrel part with 5 layers and two endcaps with 10 disks each. About 10 000 single-sided equivalent modules have to be built, each one carrying two daisy-chained silicon detectors and their front-end electronics. Back-to-back modules are used to read-out the radial coordinate. The tracker will be operated in an environment kept at a temperature of T=−10°C to minimize the Si sensors radiation damage. Heavily irradiated detectors will be safely operated due to the high-voltage capability of the sensors. Full-size mechanical prototypes have been built to check the system aspects before starting the construction.

The inner portion of the CMS microstrip Tracker consists of 3540 silicon detector modules; its construction has been under full responsibility of seven INFN (Istituto Nazionale di Fisica Nucleare) and University laboratories in Italy. In this note procedures and strategies, which were developed and perfected to qualify the Tracker Inner Barrel and Inner Disks modules for installation, are described. In particular the tests required to select highly reliable detector modules are illustrated and a summary of the results from the full Inner Tracker module test is presented. 1) INFN sez. di Catania and Universita di Catania, Italy 2) INFN sez. di Perugia and Universita di Perugia, Italy 3) INFN sez. di Pisa and Scuola Normale Superiore di Pisa, Italy 4) INFN sez. di Pisa and Universita di Pisa, Italy 5) INFN sez. di Pisa, Italy 6) INFN sez. di Torino and Universita di Torino, Italy 7) INFN sez. di Torino, Italy 8) INFN sez. di Firenze, Italy 9) INFN sez. di Bari and Dipartimento Interateneo di Fisica di Bari, Italy 10) INFN sez. di Bari, Italy 11) INFN sez. di Padova, Italy 12) INFN sez. di Firenze and Universita di Firenze, Italy 13) INFN sez. di Padova and Universita di Padova, Italy 14) INFN sez. di Perugia, Italy a) On leave from ISS, Bucharest, Romania b) On leave from IFIN-HH, Bucharest, Romania c) Corresponding Author

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, 300 μ m thick, p + on n substrate detectors were chosen. Irradiation tests have been performed on prototypes up to fluence 2×10 14  n/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 500 V).

We report the results of test beams performed at CERN using irradiated microstrip silicon detectors. The detectors were single- and double-sided devices, produced by different manufacturers and irradiated with neutrons at various fluences up to 3.6 × 1013 n/cm2. Signal-to-noise ratio, resolution and efficiency were studied for different values of the incidence angle, of the detector temperature and of the read-out pitch, as a function of the detector bias voltage. The goal of these tests was to optimize the design of the final prototypes for the CMS Silicon Strip Tracker.

An important tool for the discovery of new physics at LHC is the design of a low level trigger with an high power of background rejection. The contribution of pixel detector to the lowest level trigger at CMS is studied focusing on low-energy jet identification, matching the information from calorimeters and pixel detector. In addition, primary vertex algorithms are investigated. The performances are evaluated in terms of, respectively, QCD rejection and multihadronic jets final states efficiency.

Many kind and patient individuals have supported Protective Practices.

We present beam test results on AC-coupled, single-sided, n+-on-n type silicon microstrip detectors. We have tested the detectors before and after irradiation at a fluence of 8.3×1013 n/cm2, at different temperatures and bias voltages. Signal-to-noise ratio, spatial resolution, charge collection and overall efficiency have been measured.

Robust tracking is an essential tool to address the full range of physics which can be accessed at LHC. The CMS Collaboration has chosen the detector technology for the Si-licon Strip tracking system. Over the last few years considerable progress has been made in the understanding of the operation of silicon strip detector in the harsh environment of the LHC. An overview of recent results is given with particular emphasis on resistivity and crystal orientation of the substrate, strip capacitance and breakdown voltage.

We report selected results of laboratory measurements and beam tests of heavily irradiated microstrip silicon detectors. The detectors were single-sided devices, produced by different manufacturers and irradiated with different sources, for several total ionizing doses and fluences up to 4 /spl times/10/sup 14/ 1-MeV-equivalent neutrons per cm/sup 2/. Strip resistance and capacitance, detector leakage currents and breakdown performance were measured before and after irradiations. Signal-to-noise ratio and detector efficiency were studied in beam tests, for different values of the detector temperature and of the read-out pitch, as a function of the detector bias voltage. The goal of these test is to optimise the design of the final prototypes for the Silicon Strip Tracker of the CMS experiment at the CERN LHC collider.

This note is intended to describe the main features of the first engineered versions of the basic singlesided detector modules for the barrel and forward silicon tracker of CMS.

Abstract The new silicon tracker layout (V4) is presented. The system aspects of the construction are discussed together with the expected tracking performance. Because of the high radiation environment in which the detectors will operate, particular care has been devoted to the study of the characteristics of heavily irradiated detectors. This includes studies on performance (charge collection, cluster size, resolution, efficiency) as a function of the bias voltage, integrated fluence, incidence angle and temperature.

The CMS silicon strip tracker involves about 70 m2 of instrumented silicon, with approximately 18500 microstrip detectors read out by 5 × 106 electronics channels. It has to satisfy a set of stringent requirements imposed by the environment and by the physics expected at the LHC: low cell occupancy and good resolution, radiation hardness aided by adequate cooling, low mass combined with high stability. These conditions have been incorporated in a highly modular design of the detector modules and their support structures, chosen to facilitate construction and to allow for easy assembly and maintenance.

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 Ecm=14 TeV 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 50 cm. 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.

This paper describes the silicon microstrip tracker of the CMS experiment at the future LHC. The silicon tracker consists of a barrel part with 5 layers and two endcaps with 10 disks each. About 6500 modules will have to be built, each one carrying two daisy-chained silicon sensors and their front-end electronics. The modules have been designed to be as simple and robust as possible. Radiation damage in the silicon sensors is minimized by cooling the whole system down to -10°C. Safe operation after heavy irradiation will be possible due to the high-voltage capability of the sensors. We expect the sensors to have a signal-to-noise ratio of 10 at the end of 10years of LHC running, which still gives an efficiency of almost 100%.