Search

The Mu2e experiment at the Fermilab Muon Campus will search for the coherent neutrinoless conversion of a muon into an electron in the field of an aluminum nucleus with a sensitivity improvement by a factor of 10 000 over existing limits. Such a charged lepton flavor-violating reaction probes new physics at a scale unavailable with direct searches at either present or planned high-energy colliders. The Mu2e Trigger and Data Acquisition (TDAQ) system exploits otsdaq as its online Data Acquisition System (DAQ) solution. Developed at Fermilab, otsdaq integrates both the artdaq DAQ and the art analysis frameworks for event transfer, filtering, and processing. otsdaq is an online DAQ software suite with a focus on flexibility and scalability and provides a multi-user, web-based, interface accessible through a web browser. The read out controllers (ROCs) stream out zero-suppressed data continuously from the detector subsystems to the data transfer controllers (DTCs). The data stream is then read over the peripheral component interconnect express (PCIe) bus to a software filter algorithm that selects events which are combined with the data flux coming from a cosmic-ray veto (CRV) system. The detector control system (DCS) has been developed using the experimental physics and industrial control system (EPICS) open source platform for monitoring, controlling, alarming, and archiving. The DCS has been integrated into otsdaq. A prototype of the TDAQ system and the DCS has been built at Fermilab’s Feynman Computing Center. In this article, we report on the progress of the integration of this prototype in the online otsdaq software. [ABSTRACT FROM AUTHOR]

The Mu2e experiment at Fermilab searches for the charged-lepton flavor violating (CLFV) conversion of a negative muon into an electron in the field of an aluminum nucleus, with a distinctive signature of a monoenergetic electron of energy slightly below the muon rest mass (104.967 MeV). The Mu2e goal is to improve by four orders of magnitude the search sensitivity with respect to the previous experiments. Any observation of a CLFV signal will be a clear indication of new physics. The Mu2e detector is composed of a tracker, an electromagnetic calorimeter, and an external veto for cosmic rays surrounding the solenoid. The calorimeter plays an important role in providing particle identification capabilities, a fast online trigger filter, a seed for track reconstruction while working in vacuum, in the presence of 1-T axial magnetic field and in a harsh radiation environment. The calorimeter requirements are to provide a large acceptance for 100-MeV electrons and reach at these energies: 1) a time resolution better than 0.5 ns; 2) an energy resolution <10%; and 3) a position resolution of 1 cm. The calorimeter design consists of two disks, each one made of 674-undoped cesium iodine crystals read by two large area arrays of UV-extended silicon photomultipliers (SiPMs). We report here the construction and the test of the Module-0 prototype. The Module-0 has been exposed to an electron beam in the energy range around 100 MeV at the Beam Test Facility in Frascati. Preliminary results of timing and energy resolution at normal incidence are shown. A discussion of the technical aspects of the calorimeter engineering is also reported in this paper. [ABSTRACT FROM AUTHOR]

For the 2016 physics data runs, the L1 trigger system of the compact muon solenoid (CMS) experiment underwent a major upgrade to cope with the increasing instantaneous luminosity of the CERN LHC whilst maintaining a high event selection efficiency for the CMS physics program. Most subsystem specific trigger processor boards were replaced with powerful general purpose processor boards, conforming to the MicroTCA standard, whose tasks are performed by firmware on an field-programmable gate array of the Xilinx Virtex 7 family. Furthermore, the muon trigger system moved from a subsystem centered approach, where each of the three muon detector systems provides muon candidates to the global muon trigger (GMT), to a region-based system, where muon track finders (TFs) combine information from the subsystems to generate muon candidates in three detector regions that are then sent to the upgraded GMT. The upgraded GMT receives up to 108 muons from the processors of the muon TFs in the barrel, overlap, and endcap detector regions. The muons are sorted in two steps and duplicates are identified for removal. The first step treats muons from different processors of a TF in one detector region. Muons from TFs in different detector regions are compared in the second step. An isolation variable is calculated, using energy sums from the calorimeter trigger and added to each of the best eight muons before they are sent to the upgraded global trigger (GT) where the final trigger decision is made. The upgraded GMT algorithm is implemented on a general purpose processor board that uses optical links at 10 Gb/s to receive the input data from the muon TFs and the calorimeter energy sums, and to send the selected muon candidates to the upgraded GT. [ABSTRACT FROM AUTHOR]

After the successful completion of the SIDDHARTA experiment run with crab waist collisions, the electron-positron collider DA\Phi NE has started routine operations for the KLOE-2 detector. Similarly to the SIDDHARTA configuration, the new interaction region exploits the crab waist collision scheme, but features certain complications including the experimental detector solenoid, compensating anti-solenoids, and tilted quadrupole magnets, that lead to significant coupling of the horizontal and vertical betatron motion. It is not immediately obvious if the crab waist scheme would be as efficient in the strongly coupled case as it was in the uncoupled configuration. We have performed simulations of beam-beam interactions in the collider taking into account the real machine nonlinear lattice. In particular, we have evaluated the effect of crab waist sextupoles and beam-beam interactions on the collider dynamical aperture and energy acceptance. A new betatron tune working point has been proposed for the DA\Phi NE electron ring, and its implementation resulted in more than 20% background reduction and injection efficiency improvement. Exploiting this working point has allowed reaching the best present luminosity of 2.0 \times 10^32\ \cm^-2\ \s^-1. The numerical simulations have shown that for the given bunch currents in collision, the powering of the crab waist sextupoles should decrease the beam core blow up by a factor of 2 indicating that even higher luminosity can be achieved in DA\Phi NE thus encouraging further collider optimization. [ABSTRACT FROM PUBLISHER]

The Compact Muon Solenoid (CMS) experiment is operating at the Large Hadron Collider (LHC) with proton–proton collisions at 13-TeV center-of-mass energy and at a bunch spacing of 25 ns. Challenging running conditions for CMS are expected after the High-Luminosity upgrade of the LHC (HL-LHC). We review the CMS ECAL crystal calorimeter upgrade and present results from the first test beam studies. Particular challenges at HL-LHC are the harsh radiation environment, the increasing data rates, and the extreme level of pile-up events, with up to 200 simultaneous proton–proton collisions. Precision timing can be exploited to reduce the effect of the pileup. We report on the timing resolution studies performed with test beams. We discuss the new readout and trigger electronics, which must be upgraded due to the increased trigger and latency requirements at the HL-LHC. [ABSTRACT FROM AUTHOR]

The data acquisition (DAQ) system of the CMS experiment at the CERN Large Hadron Collider assembles events at a rate of 100 kHz, transporting event data at an aggregate throughput of 100 GB/s to the high level trigger (HLT) farm. The HLT farm selects interesting events for storage and offline analysis at a rate of around 1 kHz. The DAQ system has been redesigned during the accelerator shutdown in 2013/14. The motivation is twofold: Firstly, the current compute nodes, networking, and storage infrastructure will have reached the end of their lifetime by the time the LHC restarts. Secondly, in order to handle higher LHC luminosities and event pileup, a number of sub-detectors will be upgraded, increasing the number of readout channels and replacing the off-detector readout electronics with a \mu \ TCA implementation. The new DAQ architecture will take advantage of the latest developments in the computing industry. For data concentration, 10/40 Gb/s Ethernet technologies will be used, as well as an implementation of a reduced TCP/IP in FPGA for a reliable transport between custom electronics and commercial computing hardware. A Clos network based on 56 Gb/s FDR Infiniband has been chosen for the event builder with a throughput of \sim 4~\Tb/s. The HLT processing is entirely file based. This allows the DAQ and HLT systems to be independent, and to use the HLT software in the same way as for the offline processing. The fully built events are sent to the HLT with 1/10/40 Gb/s Ethernet via network file systems. Hierarchical collection of HLT accepted events and monitoring meta-data are stored into a global file system. This paper presents the requirements, technical choices, and performance of the new system. [ABSTRACT FROM PUBLISHER]

Characteristics of ripples generated as transient responses with idealized current patterns in synchrotrons are studied along with practical applications. The ripples intrinsically occur in synchrotron magnets as a driven harmonic oscillation whenever ramp pattern currents are applied to the magnets. In realistic synchrotron magnet circuits, additionally, damping resistors and interconnection types should be taken into account, because they largely change such circuit parameters as resistance and capacitance. In this paper, effects of damping resistance and conductor types, such as cables and bus-bars, on intrinsic ripples are studied. Simulated results are obtained within realistic circumstances of J-PARC Main-ring Synchrotron in the present 30 GeV operations. [ABSTRACT FROM PUBLISHER]

The coupled RFQ-SFRFQ (CRS) linac, which couples radio frequency quadrupole (RFQ) and separated function structure radio frequency quadrupole (SFRFQ) into a single cavity, is a novel compact accelerator developed in Peking university. In this paper, the detailed design of the remote control system for the CRS linac was presented. The hardware configuration of the system consists of an industry computer (IPC) and several different types of Programming Logic Controller (PLC) modules. The high voltage protection and cavity tuning control were discussed. The control software was developed with Windows Control Center (WinCC) and Step7 based on C script and Ladder Diagram (LAD) respectively. The interlock protection mechanism was introduced into the control system and the operating data can be flexibly acquired from the archives in structured query language (SQL) sever 2005. This system has been successfully implemented for the operation of an upgraded \ He^+ ion injector. For the input beam optimization, a parameter scanner code was developed to optimize the beam transmission in low energy beam transport (LEBT) section, and the final optimized beam parameters were obtained. [ABSTRACT FROM PUBLISHER]

The CMS Silicon Strip Tracker is the largest detector of its kind ever operated, with a silicon surface area of about 200 m^2. The Silicon Strip Tracker is the sub-detector with the highest number of detector modules within the CMS experiment. Given the complexity of the device, a variety of tools were developed and are used to determine the status of the detector in real time and allow for data qualification and corrective actions when needed. In this paper we describe the monitoring techniques that are used to safely operate the detector and assess the state of its calibration. [ABSTRACT FROM PUBLISHER]

Run control systems of modern high-energy particle physics experiments have requirements similar to those of today's Internet applications. The Compact Muon Solenoid (CMS) collaboration at CERN's Large Hadron Collider (LHC) therefore decided to build the run control system for its detector based on web technologies. The system is composed of Java Web Applications distributed over a set of Apache Tomcat servlet containers that connect to a database back-end. Users interact with the system through a web browser. The present paper reports on the successful scaling of the system from a small test setup to the production data acquisition system that comprises around 10.000 applications running on a cluster of about 1600 hosts. We report on operational aspects during the first phase of operation with colliding beams including performance, stability, integration with the CMS Detector Control System and tools to guide the operator. [ABSTRACT FROM AUTHOR]

Automatic, synchronous and of course reliable population of the condition database is critical for the correct operation of the online selection as well as of the offline reconstruction and data analysis. We will describe here the system put in place in the CMS experiment to automate the processes to populate centrally the database and make condition data promptly available both online for the high-level trigger and offline for reconstruction. The data are “dropped” by the users in a dedicated service which synchronizes them and takes care of writing them into the online database. Then they are automatically streamed to the offline database, hence immediately accessible offline worldwide. This mechanism was intensively used during 2008 and 2009 operation with cosmic ray challenges and first LHC collision data, and many improvements were done so far. The experience of this first years of operation will be discussed in detail. [ABSTRACT FROM PUBLISHER]

The Level-1 Trigger plays a major role in the CMS experiment allowing the reduction of the raw event rate at the Large Hadron Collider. Its decision is based on information from the electromagnetic and hadronic calorimeters as well as the muon detectors. The electronics of the electromagnetic calorimeter generate and deliver basic quantities called “Trigger Primitives” which correspond to local energy deposits created by electromagnetic showers. In order to ensure the correct generation of the trigger primitives by the electronics, a special software called an emulator has been implemented. It is able to reproduce the ECAL trigger functionalities at the bit level using the same inputs and identical output format. It is configured in exactly the same way as the hardware. [ABSTRACT FROM PUBLISHER]

Due to an expected increase in radiation damage under super-LHC conditions, we propose to substitute the scintillator tiles in the original design of the hadronic endcap (HE) calorimeter with quartz plates. Quartz is shown to be radiation hard. Using wavelength shifting fibers, it is possible to collect efficiently the Čerenkov light generated in quartz plates. This paper summarizes the results from various test beams, bench tests, and Geant4 simulations done on methods of collecting light from quartz plates, as well as radiation hardness tests on quartz material. [ABSTRACT FROM AUTHOR]

The CMS data acquisition system is designed to build and filter events originating from 476 detector data sources at a maximum trigger rate of 100 kHz. Different architectures and switch technologies have been evaluated to accomplish this purpose. Events will be built in two stages: the first stage will be a set of event builders called front-end driver (FED) builders. These will be based on Myrinet technology and will pre-assemble groups of about eight data sources. The second stage will be a set of event builders called readout builders. These will perform the building of full events. A single readout builder will build events from about 60 sources of 16 kB fragments at a rate of 12.5 kHz. In this paper, we present the design of a readout builder based on TCP/IP over Gigabit Ethernet and the refinement that was required to achieve the design throughput. This refinement includes architecture of the readout builder, the setup of TCP/IP, and hardware selection. [ABSTRACT FROM AUTHOR]

The CMS Muon System exploits three different detection technologies in both the central and forward regions, in order to provide a good muon identification and efficient event selection via a multi-level trigger. In summer 2006 the CMS solenoid has been switched on for the first time, generating success- fully the designed magnetic field of B = 4 T. During this period also a slice of the CMS detector was operational (the "CMS Cosmic Challenge") including a subset of detectors from all three muon subsystems along with the muon hardware alignment. A dedicated CMS cosmic muon trigger had to l)e set-up, which was based on the Level-1 trigger inputs from the muon subsystems. The CMS subsystems were integrated in the central DAQ, detector control and data quality monitoring. Cosmic data were taken in different trigger configurations in order to study the behavior of muon detectors in the magnetic field, combined detector operations and trigger synchronization. The recorded data are used to study alignment with tracks, to verify and tune the reconstruction software. The layout and status of the CMS muon system is presented and results of the recent cosmic challenge data taking are discussed. [ABSTRACT FROM AUTHOR]

The Data Acquisition System of the Compact Muon Solenoid experiment at the Large Hadron Collider reads out event fragments of an average size of 2 kB from around 650 detector front- ends at a rate of up to 100 kHz. The first stage of event-building is performed by the Super-Fragment Builder employing custom-built electronics and a Myrinet optical network. It reduces the number of fragments by one order of magnitude, thereby greatly decreasing the requirements for the subsequent event-assembly stage. Back-pres- sure from the down-stream event-processing or variations in the size and rate of events may give rise to buffer overflows in the subdetector's front-end electronics, which would result in data corruption and would require a time-consuming re-sync procedure to recover. The Trigger-Throttling System protects against these buffer overflows. It provides fast feedback from any of the subdetector front-ends to the trigger so that the trigger can be throttled be- fore buffers overflow. This paper reports on new performance measurements and on the recent successful integration of a scaled-down setup of the described system with the trigger and with front-ends of all major subdetectors. The ongoing commissioning of the full-scale system is discussed. [ABSTRACT FROM AUTHOR]

The Grid offers physicists far more resources than have previously been available by combining elements in computing centers around the world into a globally accessible resource. However, in order to harness this computing power many steps need to be performed for job creation and management and data discovery. ASAP (ARDA Support for CMS Analysis Process) was developed to make this step as simple and straightforward as possible for physicists working on the Compact Muon Solenoid (CMS) experiment at CERN. ASAP transfers a local application to the Grid by packaging the application, discovering the location of input data then creating, submitting and monitoring jobs. One of the main components of the system is that users can delegate responsibility for their tasks to the ASAP server which can take actions on behalf of the user to ensure that tasks are completed successfully. The system can operate in the traditional push model but can also be used by agents executing on the Grid to pull jobs to the worker node for execution. [ABSTRACT FROM AUTHOR]

The CERN Large Hadron Collider (LHC) will collide two counter rotating proton beams. The energy stored in each beam is about 350 MJ. If there is a failure in an element of the accelerator, the resulting beam losses could cause damage not only to the accelerator itself, but also to the physics experiments installed. Within the Compact Muon Solenoid experiment (CMS), the use of a Beam Condition Monitor (BCM) is planned to monitor a possible fast increase of the particle flux near the interaction point. The system will flag the onset of adverse beam conditions within the CMS experiment, and, if necessary, input into the beam abort system of the LHC requesting a fast beam dump. Constraints on BCM design from radiation hardness, a minimal material and services budget, and the need for fast signals from sensors with high sensitivity and a large dynamic range, have led to the investigation of synthetic chemical vapor deposited (CVD) diamond for the BCM sensor. In a 5 GeV hadron beam the response of CVD diamonds was tested in fluxes ranging from single minimium ionizing particles (MIPs) to 108 MIPs per cm2, delivered over 40 ns. The signal response, linearity, and stability of both unirradiated and irradiated sensors were tested over this flux range, and will be presented herein. The results confirm the applicability of CVD diamond for this beam monitoring application. [ABSTRACT FROM AUTHOR]

Phase-controlled operation of thyristor power rectifiers requires instantaneous phase information of the fundamental component of the grid voltage in order to generate the proper gating sequence. In many high-power, high-precision applications, such us driving the bending magnets of large particle accelerators, the power converters are fed from a local grid, which produces significant frequency variations and large voltage notches super-imposed to the sinusoidal AC voltage due to the commutation interval. These strong disturbances impose some difficulties in measuring the phase of the mains, affecting the precision of the converter. In this paper, we present a new method to generate a fast and precise synchronism signal based on the concept of space vectors. The proposed method allows to track line frequency changes within one cycle of the mains in spite of the large voltage notches produced by the commutation overlap angle. Simulation and experimental results are provided. [ABSTRACT FROM AUTHOR]

The Trigger Supervisor is an online software system designed for the CMS experiment at CERN. Its purpose is to provide a framework to set up, test, operate and monitor the trigger components on one hand and to manage their interplay and the information, exchange with the run control part of the data acquisition system on the other. The Trigger Supervisor is conceived to provide a simple and homogeneous client interface to the online software infrastructure of the trigger subsystems. The functional and nonfunctional requirements, the design, the operational details, and the components needed in order to facilitate a smooth integration of the trigger software in the context of CMS are described. [ABSTRACT FROM AUTHOR]

The CMS experiment at the LHC, CERN, will operate the largest tracker in the world entirely made of silicon detectors. The collaboration is facing the quality assurance work to prove the reliability and performance of the various parts produced by industry. A status report on the CMS Tracker is given, including the validation of single modules up to larger integrated substructures [ABSTRACT FROM PUBLISHER]

The resistive plate chambers (RPCs) muon trigger electronics of the Compact Muon Solenoid (CMS) detector performs a number of tasks: synchronization of detector signals, optical data transmission from the detector to the trigger electronics, pattern recognition, muons momentum measurement, selection of track candidates. For the diagnostic purposes, as well as for the calibration and real-time monitoring of the RPC detectors and electronic hardware, a set of flexible diagnostic modules was designed and implemented into the field programmable gate arrays on which the trigger electronics is based. These include: multichannel counters, timing histograms, test pulses generators, diagnostic readout and data spying ("snap-shots" of the data stream). Test results presented in this paper, including tests with Large Hadron Collider-like muon beam, illustrate the performance and the usefulness of these diagnostic modules [ABSTRACT FROM PUBLISHER]

The Compact Muon Solenoid (CMS) is one of two general purpose detectors which are foreseen to operate at the Large Hadron Collider (LHC), which is presently being built at the European laboratory for particle physics (CERN) in Switzerland. The Central Tracker of CMS consists of a Pixel System, which is located close to the interaction point and a Silicon Strip Tracker (SST) which instruments the intermediate and outer region. The SST is composed of 15148 Silicon Microstrip Detector Modules which contain the readout electronics (hybrids) and sensors. These modules will be assembled into substructures with control electronics and optics for transmitting data. The substructures will be integrated into the subsystems of the SST. The SST will be operated for up to ten years in the harsh radiation environment of the LHC. The lifetime of the SST will be extended by operating the detector at lowered temperature. The sensors, which are very delicate with respect to radiation damage, will be operated at a maximum temperature of -10degC. Since the assembly of the modules as well as the mounting on substructures is done at room temperature, tests in a CMS-like environment are necessary to prove the mechanical and electrical stability [ABSTRACT FROM PUBLISHER]

The front end driver (FED), is a 9U 400 mm VME64x card designed for reading out the compact muon solenoid (CMS), silicon tracker signals transmitted by the APV25 analogue pipeline application specific integrated circuits. The FED receives the signals via 96 optical fibers at a total input rate of 3.4 GB/sec. The signals are digitized and processed by applying algorithms for pedestal and common mode noise subtraction. Algorithms that search for clusters of hits are used to further reduce the input rate. Only the cluster data along with trigger information of the event are transmitted to the CMS data acquisition system using the S-LINK64 protocol at a maximum rate of 400 MB/sec. All data processing algorithms on the FED are executed in large on-board field programmable gate arrays. Results on the design, performance, testing and quality control of the FED are presented and discussed [ABSTRACT FROM PUBLISHER]

On the Compact Muon Solenoid (CMS) experiment for large hadron collider (LHC) at CERN laboratory, the drift tube chambers are responsible for muon detection and precise momentum measurement. In this paper the first level of the read out electronics for these drift tube chambers is described. These drift tube chambers will be located inside the muon barrel detector in the so-called minicrates (MCs), attached to the chambers. The read out boards (ROBs) are the main component of this first level data acquisition system, and they are responsible for the time digitalization related to Level 1 Accept (L1A) trigger of the incoming signals from the front-end electronics, followed by a consequent data merging to the next stages of the data acquisition system. ROBs' architecture and functionality have been exhaustively tested, as well as their capability of operation beyond the expected environ- mental conditions inside the CMS detector. Due to the satisfactory results obtained, final production of ROBs and their assembly in the MCs has already started. A total amount of 250 MCs and approximately 1500 ROBs are being produced and tested thoroughly at CLEMAT (Spain). One set of tests, the burn-In tests, will guarantee ten years of limited maintenance operation. An overview of the system and a summary of the different results of the tests per- formed on ROBs and MCs will be presented. They include acceptance tests for the production chain as well as several validation tests that insure proper operation of the ROBs beyond the CMS detector conditions. [ABSTRACT FROM AUTHOR]

The multiple-gain preamplifier (MGPA) is a three-gain channel 0.25 pm CMOS chip matched to the noise and linearity requirements of the electromagnetic calorimeter for the Compact Muon Solenoid (CMS) experiment. A choice of external feedback components to the first-stage amplifier allows the chip to match the different full-scale signal and noise requirements for both barrel and end-cap regions of the detector. For the barrel (end-cap) application the noise is less than 10000(3,500) electrons at a peaking time of 40 ns and an integral nonlinearity of approximately ±0.1% full-scale is achieved for all three gain ranges. Details of the design and performance are presented, including measurements of nonlinearity, pulse-shape matching, noise, and radiation tolerance. [ABSTRACT FROM AUTHOR]

The concept of an active integrated dosimetric sensor for the radiation monitoring of the Compact Muon Solenoid experiment at the CERN (European Center for Nuclear Research) Large Hadron Collider is presented. The sensor, based on RadFET, OSL, psi-n diode, and pad detector dosimeters, will measure both ionizing and nonionizing energy losses in the harsh radiation environment produced by hadron interactions. [ABSTRACT FROM AUTHOR]

Experiments with a cooled antiproton beam at the future accelerator facility at the Gesellschaft für Schwer Ionenforschung, Darmstadt, Germany, will be performed with the 4π detector proton antiproton at Darmstadt comprising a high-resolution, compact, and fast homogeneous electromagnetic calorimeter to detect photons between 10 MeV and 10 GeV energy inside a superconducting solenoid (2 T). PbWO4 (PWO) crystals, readout with large size avalanche photodiodes, represent an envisaged detector concept The first results of a new generation of significantly improved PWO crystals, operated at different temperatures, are presented and discussed in detail. The requirements for the photo sensor are outlined based on first test measurements. A new fast hybrid photomultiplier (PLANACON 85001-501, BURLE) with channel plate amplification was investigated for comparison. [ABSTRACT FROM AUTHOR]

The large hadron collider (LHC) at the Centre Européenne pour Ia Recherche Nucléaire (CERN), Geneva, Switzer- land, is a proton-proton collider with a luminosity of 1034/cm²s and will be working for ten years (starting in 2007). Compact muon solenoid (CMS) will be one of the four general-purpose detectors. The CMS tracker consists of ten barrel layers, plus 2 × 9 end cap discs, which amounts to a total of 24328 silicon sensors with a total area of 206 m² silicon, covering a pseudorapidity of &verbar;η&verbar; ≤ 2.5. For the sensors close to the beam pipe, fluences of 1.6˙1014n1 MeV/cm² are expected over the ten-year lifetime. To guarantee the functionality of the single-side silicon sensors during the runtime of the LHC, quality assurance was developed. In the two Irradiation Qualification Centers (IQCs) in Karlsruhe, Germany, and Louvain-la-Neuve, Belgium, a fraction of 1 % of the sensors are electrically qualified. In Karlsruhe, the sensors are irradiated with 26-MeV protons. and in Louvain-la-Neuve with neutrons at an average energy of 20 MeV. For reasons of flux uncertainties in the CMS tracker, sensors are irradiated with a fluence 50% higher than predicted. For standard float zone silicon, large material dependencies have been observed under irradiation resulting in changes to various electrical parameters. To guarantee the functionality of the sensors in the tracker, it is very important to know these parameters. These electrical parameters have been determined before and after irradiation and are discussed in the following sections. [ABSTRACT FROM AUTHOR]

High-energy physics experiments, such as the com- pact muon solenoid (CMS) at the large hadron collider (LHC), have large-scale data processing computing requirements. The grid has been chosen as the solution. One important challenge when using the grid for large-scale data processing is the ability to monitor the large numbers of jobs that are being executed simultaneously at multiple remote sites. The relational grid monitoring architecture (R-GMA) is a monitoring and information management service for distributed resources based on the GMA of the Global Grid Forum. In this paper, we report on the first measurements of R-GMA as part of a monitoring architecture to be used for batch submission of multiple Monte Carlo simulation jobs running on a CMS-specific LHC computing grid test bed. Monitoring information was transferred in real time from remote execution nodes back to the submitting host and stored in a database. In scalability tests, the job submission rates supported by successive releases of R-GMA improved significantly, approaching that expected in full-scale production. [ABSTRACT FROM AUTHOR]

The detector control unit (DCU) is an ASIC developed as the central building block of a monitoring system for the Tracker of the Compact Muon Solenoid (CMS) experiment. Leakage currents in the Silicon detectors, power supply voltages of the readout electronics and local temperatures will be monitored in order to guarantee safe operating conditions during the 10-years lifetime in the large hadron collider (LHC) environment. All these measurements can be performed by an A/D converter preceded by an analog multiplexer and properly interfaced to the central control system. The requirements in terms of radiation tolerance, low-power dissipation and integration with the rest of the system led to the design of a custom integrated circuit. Its structure and characteristics are described in this paper. [ABSTRACT FROM AUTHOR]

Presents test beam results using Compact Muon Solenoid pixel readout electronics. Role of pixel detectors using synthetic diamond; Suitability of the Compact Muon Solenoid and ATLAS pixel detectors; Features of diamond pixel detectors; Properties of chemical vapor deposited diamond that need to be addressed before diamond pixel detectors are viable.

Describes the components, hardware and software of the prototype control system developed for the compact muon solenoid (CMS) tracker. Uses of programmable embedded electronics; Features of a small-scale prototype of the control system for the CMS tracker; Requirement of the distributed nature of the system for the parameter database.

Presents a study which developed a multigain transimpedance amplifier custom integrated circuit for the readout of avalanche photodiode and vacuum phototriode in the compact muon solenoid electromagnetic calorimeter. Principle of operation of the custom integrated front-end circuit; Overview of the block diagram of the circuit; Circuit descriptions of the sensitive parts of the design linked to the performance needed.

Focuses on a study which described the mapping of the magnetic field of the Belle detector's large superconducting solenoid. Main purpose of the Belle detector; Discussion on the Belle spectrometer magnet and the QCS system; Field mapping device used in the study; Calibration and measurement; Reconstruction of field map.

Presents a study on the readout system of the Compact Muon Solenoid electromagnetic calorimeter. Requirements of the readout system; Elements of the readout system; Interfaces of the readout system.

Focuses on a study which presented the design of the compact muon solenoid monitoring light source and distribution system. Selection of monitoring wavelength; Performance of a laser system; Summary.

Presents information on a study which investigated the influence of radiation damage on the ageing behavior of InGaAs lasers and photodiodes. Reliability of lasers and photodiodes; Failure rates and predictions for Compact Muon Solenoid; Results and discussion; Conclusions.

Presents a study which discussed a computer software approach for readout and data acquisition in compact muon solenoid. Components of the software; Conclusions.

Presents information on a trigger system for the first compact muon solenoid (CMS) tracking beam test. Functionalities of the CMS milestones trigger; Description of the trigger system; Details on the four different parts of the system.

Presents results from an analysis of the Time Projection Chamber (TPC) of the Solenoidal Tracker at RHIC (STAR) detector. Nature of results generated by the application of the TPC; Features measured; Discussion of the results.

Provides information on the Solenoidal Tracker at RHIC experiment which will be using PIN-photodiodes for the first year of beam running in order to detect beam loss before the silicon drift detector is put into place in 2000. Experimental set-up; Operating principle; Test results; Conclusion.