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The operation of the compact muon solenoid drift tubes (DTs) muon detectors at the high-luminosity large hadron collider will be possible only with an upgrade of the current readout and trigger electronics, which are based on very old technology and directly exposed to radiation, hence particularly sensitive to aging. A new level 1 trigger primitive generator, based on the use of an original compact Hough transform (CHT) algorithm, is being designed with the goal of its implementation in the state-of-the-art field programmabla gate array (FPGA) devices. The algorithm can identify the muon track segment parameters and must be combined with a majority mean-timer in order to assign the muon to its parent bunch crossing. The algorithm is expected to be deployed on FPGAs and has a few \mu \texts latency for decision taking, with efficiency and resolution equal or higher with respect to the ones provided by the currently running algorithm. The major challenges are parallelization of the algorithm, fast readout of the CHT parameter matrix, the capability of handling data from a large array of DTs in the minimal number of FPGAs, and coping with the latency requirements. These issues will be addressed proposing constructive solutions. [ABSTRACT FROM AUTHOR]

The Belle II experiment will go into operation at the upgraded SuperKEKB collider in 2016. SuperKEKB is designed to deliver an instantaneous luminosity \cal L = 8 \times 10^35~\cm^ - 2~\s^ - 1. The experiment will therefore have to cope with a much larger machine background than its predecessor Belle, in particular from events outside of the interaction region. We present the concept of a track trigger, based on a neural network approach, that is able to suppress a large fraction of this background by reconstructing the z (longitudinal) position of the event vertex within the latency of the first level trigger. The trigger uses the hit information from the Central Drift Chamber (CDC) of Belle II within narrow cones in polar and azimuthal angle as well as in transverse momentum (“sectors”), and estimates the z-vertex without explicit track reconstruction. The preprocessing for the track trigger is based on the track information provided by the standard CDC trigger. It takes input from the 2D track finder, adds information from the stereo wires of the CDC, and finds the appropriate sectors in the CDC for each track. Within the sector, the z-vertex is estimated by a specialized neural network, with the drift times from the CDC as input and a continuous output corresponding to the scaled z-vertex. The neural algorithm will be implemented in programmable hardware. To this end a Virtex 7 FPGA board will be used, which provides at present the most promising solution for a fully parallelized implementation of neural networks or alternative multivariate methods. A high speed interface for external memory will be integrated into the platform, to be able to store the \cal O(10^9) parameters required. The contribution presents the results of our feasibility studies and discusses the details of the envisaged hardware solution. [ABSTRACT FROM AUTHOR]

We have developed readout electronics for the central drift chamber (CDC) of the Belle-II detector. The space near the endplate of the CDC for installation of the electronics was limited by the detector structure. Due to the large amounts of data generated by the CDC, a high-speed data link, with a greater than one gigabit transfer rate, was required to transfer the data to a back-end computer. A new readout module was required to satisfy these requirements. This module processes 48 signals from the CDC, converts them to digital data and transfers it directly to the computer. All functions that transfer digital data via the high speed link were implemented on the single module. We have measured its electrical characteristics and confirmed that the results satisfy the requirements of the Belle-II experiment. [ABSTRACT FROM AUTHOR]

In order to measure the energy of neutron fields, with energy ranging from 8 keV to 1 MeV, a new primary standard is being developed at the IRSN (Institute for Radioprotection and Nuclear Safety). This project, \mu-TPC (Micro Time Projection Chamber), carried out in collaboration with the LPSC (Laboratoire de Physique Subatomique et de Cosmologie), is based on the nuclear recoil detector principle. The instrument is presented with the associated method to measure the neutron energy. This article emphasizes the proton energy calibration procedure and energy measurements of a neutron field produced at 127 keV with the IRSN facility AMANDE. [ABSTRACT FROM PUBLISHER]

Hadron physics has been an essential part of the physics program with the CLAS detector in experimental hall B at Thomas Jefferson National Accelerator Facility (Jefferson Lab). With the 12 GeV upgrade of the CEBAF machine, hadron physics in Hall B will be extended to a new domain of higher mass resonances and the range of higher transferred momentum using up to 11 GeV electron beams and the upgraded CLAS12 detector. In this paper, status of the hall B superconducting magnets for the CLAS12 detector is presented. [ABSTRACT FROM PUBLISHER]

We present a global time fit to determine the reference time event-by-event in an array of drift cells. The method is applied to the monitored drift tube tracking chambers (MDT) of the muon spectrometer of the ATLAS experiment at the large hadron collider (LHC). During operation with proton-proton collisions, the muon trigger is based on dedicated fast detectors and the readout is clocked at the beam crossing frequency of 40 MHz. A method has been developed for tracking particles through the MDT chambers which works without a precisely timed external trigger. This study was conceived to exploit the MDT tracking capabilities in non standard operation of the ATLAS detector, e.g., during commissioning with cosmic rays when there is no time correlation with the LHC clock frequency. Results obtained using an asynchronous trigger, with a high energy muon beam from the CERN SPS, and with cosmic rays are reported. [ABSTRACT FROM AUTHOR]

In modern high energy and nuclear physics experiments, the complexity of gas detectors and their operation in areas not accessible during the data-taking periods require dedicated gas and safety systems running automatically and controlled by PC. In the FINUDA experiment, to control the gas systems of the drift and He chambers and to monitor the relevant parameters such as helium atmosphere purity and gas mixture composition which affect the experimental performances, three programs were written in National Instruments (NI) LabVIEW and Datalogging and Supervisory Control environment. Two safety systems work continuously to check the hydrocarbon leakages, inside and outside the He Chamber: pre-alarm and alarm signals feed a NI Field Point, where a real time program sends, via Ethernet, the FINUDA safety status to all detectors. [ABSTRACT FROM AUTHOR]

In the ATLAS muon spectrometer, large drift-tube chambers are used for precision tracking. The chambers will be operated at a high neutron and γ background resulting in count rates of up to 500 Hz cm-2 corresponding to 300 kHz per tube. The spatial resolution of the drift tubes is degraded from 82 µm without background to 108 µm at 500 Hz cm-2 background count rate. Due to afterpulsing in the Ar/CO2 gas mixture used in the drift tubes, ionizing radiation causes more than one hit in a tube within the maximum drift time of about 800 ns which is expected for magnetic field strengths around 1.2 T. In order to limit the count rate, the drift tubes are read out with an artificial dead time of 790 ns which causes an efficiency loss of 23% at a rate of 300 kHz per tube. The space-to-drift-time relationship of the tubes varies with background rate, temperature, and magnetic field strength. The mean magnetic field strength in a muon chamber is 0.4 T on the average, but may vary by up to 0.4 T within a chamber. The space-to-drift-time relationship must therefore be determined in short time intervals with an accuracy better than 20 µm using muon tracks and applying corrections for measured magnetic field variations. [ABSTRACT FROM AUTHOR]

In order to ensure that the resistive plate chambers used in the ATLAS experiment will not show, during their operation, any abnormal aging effect which could degrade their performances, an aging test is being performed at X5-GIF, CERN's gamma irradiation facility. In this paper, the latest results are presented, together with an example of successful damage recovery technique. [ABSTRACT FROM AUTHOR]

We have developed and successfully tested a prototype of a new high position resolution hybrid X-ray detector. It contains a thin-wall lead glass capillary plate converter of X-rays combined with a microgap parallel-plate avalanche chamber operating in various gas mixtures at 1 atm. The operation of these converters was studied in a wide range of X-ray energies (from 6 to 60 keV) at incident angles varying from 0-90°. The detection efficiency, depending on the geometry, photon's energy, incident angle and the mode of operation was between 5-30% in single step mode and up to 50% in a multi-layered combination. Depending on the capillary's geometry, the position resolution achieved was between 50-250 µm in digital form and was practically independent of the photon's energy or gas mixture. The usual lead glass capillary plates operated without noticeable charging up effects at counting rates of 50 Hz/mm² and hydrogen treated capillaries—up to 105 Hz/mm². The developed detector has several important potential advantages over the exciting X-ray detectors and may open new possibilities for medical imaging, for example in mammography, portal imaging, radiography (including security devices), as well as many other applications. [ABSTRACT FROM AUTHOR]

Multiwire proportional chambers (MWPCs) are widely used in many different disciplines. The quality of the results depends on many factors such as gas gain, detector count rate, detection efficiency, spatial and energy resolution, and uniformity. We report here on a detailed study on how to optimize all these features, in particular regarding the use of MWPC at synchrotron radiation sources. Detector behavior has been analyzed in relation to geometry of the wire planes; electric field; frames design and window geometry; and gas parameters. From this study, general optimization criteria were obtained. The results of this study have been applied to produce a new design for a detector required to perform time-resolved X-ray diffraction/scattering experiments in the submillisecond time scale with a spatial resolution of 0.03 cm. In addition, we report on the outcome of simulations aiming at understanding the influence of manufacturing defects as well as gas quality. [ABSTRACT FROM AUTHOR]

The Atlas muon spectrometer relies on Monitored Drift Tubes (MDTs) for track reconstruction in most regions. Expected count rates due to photons reach up to 1500 Hz/cm for the innermost MDTs. For a gas gain of 2middot104 this corresponds to an overall accumulated charge of up to 0.6 C/cm which the MDTs must be able to withstand in 10 years of LHC operation without a degradation in their performance. With the main MDT parameters and the design frozen and chamber production well under way the focus of present aging studies is on testing final Atlas chambers instead of using small, dedicated setups under very well controlled conditions as in the past. This paper summarizes the results of such a study performed at the CERN Gamma Irradiation Facility GIF, that aims to emulate LHC background conditions. One of the main goals was to evaluate the principle of gas recirculation and a prototype of the Atlas circulation system [ABSTRACT FROM PUBLISHER]

We report the electron and hole charge transport properties of semi insulating CdTe:Cl grown by the Travelling Heater Method (THM). An alpha-particle Time of Flight (TOF) method was used to measure electron and hole drift mobility, with room temperature values of 880 cm2 /Vs for electrons and 90 cm2/Vs for holes. The variation in mobility was also investigated as a function of temperature, with electron and hole mobilities at 190 K of 1150 cm2 /Vs and 20 cm2/Vs respectively. Using a Hecht analysis the electron and hole mobility-lifetime products were also measured over the same temperature range, with values at room temperature of 8times10-4 cm2/V and 7times10-5 cm 2/V respectively. Time-resolved ion beam induced charge (IBIC) imaging was used to produce micrometer resolution maps of electron drift mobility and signal amplitude, which showed excellent spatial uniformity [ABSTRACT FROM PUBLISHER]

A cosmic ray measurement facility has been set up at Ludwig-Maximilians-University Munich (LMU) and is used at present to commission and calibrate Monitored Drift Tube (MDT) chambers for the muon spectrometer of the ATLAS experiment. Each of these chambers-produced in collaboration with the Max-Planck-Institut fuumlr Physik and the Joint Institute for Nuclear Research in Dubna-consists of 432 drift tubes with a diameter of 3 cm, which are arranged in 2times3 layers, and measures 3.8 mtimes2.2 mtimes0.5 m. At the LMU site, the MDT chambers are completed, equipped with their final front-end electronics and taken into operation for the first time. The gas leak rate of the chamber is determined and its high voltage stability is tested. The response of all drift tubes and its homogeneity across the chamber is measured in the Cosmic Ray Facility. Two MDT chambers which were precisely mapped with an X-Ray tomograph provide reference tracking for the enclosed third chamber which is to be calibrated. The sense wire positions are determined from a comparison of the drift time measurements with the reference tracks. The geometry of the tested chamber-the grid constants of the drift tubes in a layer, the distances and tilt angles of the layers-can then be derived from these positions. Alignment systems are used to monitor chamber movements at the micrometer level. In the ongoing series commissioning, a rate of one chamber per week has been achieved. The parameters describing the geometry of the MDT chambers are determined with a precision in the 10 mum range. The measurements with cosmic muons complement the chamber surveys performed during construction and will provide an important input for the calibration of the entire ATLAS muon spectrometer [ABSTRACT FROM PUBLISHER]

The Central Outer Tracker (COT) is a large axial drift chamber in the Collider Detector at Fermilab operating with a gas mixture that is 50/50 argon/ethane with an admixture of 1.7% isopropanol. In its first two years of operation the COT showed unexpected aging with the worst parts of the chamber experiencing a gain loss of ~50% for an accumulated charge of ~35 mC/cm. By monitoring the pulse height of hits on good tracks, it was possible to determine the gain as a function of time and location in the chamber. In addition, the currents of the high voltage supplies gave another monitor of chamber gain and its dependence on the charge deposition rate. The aging was worse on the exhaust end of the chamber consistent with polymer buildup as the gas flows through the chamber. The distribution in azimuth suggests that aging is enhanced at lower temperatures, but other factors such as gas flow patterns may be involved. Elemental and molecular analysis of the sense wires found a coating that is mostly carbon and hydrogen with a small amount of oxygen; no silicon or other contaminants were identified. High resolution electron microscope pictures of the wire surface show that the coating is smooth with small sub-micron nodules. In the course of working with the chamber gas system, we discovered a small amount of O 2 is enough to reverse the aging. Operating the chamber with ~100 ppm of O2 reversed almost two years of gain loss in less than 10 days while accumulating les2 mC/cm [ABSTRACT FROM PUBLISHER]

In order to explore new physics in B-meson decays we plan to upgrade the KEK B-factory to a luminosity of 5 × 1035 cm-2s-1. In parallel we are developing a new pipelined data acquisition system for the Belle detector to cope with higher trigger rates of up to 30 kHz and severe background conditions. In order to reduce development and maintenance costs, we have adopted a modular design for these new readout electronics. The chosen architecture consists of a common readout platform, upon which are mounted subdetector specific parts, customized to meet the readout requirements of each sub detector component. As an example of this new architecture, we present in this paper the design of drift chamber electronics. The drift chamber readout utilizes the AMT-3 time-to-digital converter chip, originally developed for the ATLAS experiment, which satisfies the performance requirement for current and future Belle drift chamber readout. A data transfer performance test with emulation modules, mounted on the common platform, shows that the new readout electronics works well at a more than 30 kHz input trigger rate. [ABSTRACT FROM AUTHOR]

An X-ray setup has been developed to measure wire positions of straw tube drift chambers of the COMPASS experiment with a charge-coupled device. In an automatic scanning procedure wire positions can be determined with an accuracy better than 30 μm inside an area of 3.6 × 3.6 m2. This accuracy is achieved by means of multiple stereo recordings of the detector wires and external reference wires. Within small distances of several centimeters the achieved accuracy is on the order of a few micrometers. [ABSTRACT FROM AUTHOR]

Drift chamber readout electronics for over 8000 channels with concurrent data recording and readout have been developed to update the NA4S experiment existing system. Drift times are measured in bins of 1.56 its with respect to the continuously running 40 MHz experiment clock. The architecture is based on commercially available hardware for cost effectiveness and flexibility. The design of the electronics is described, and results from data-taking runs are presented. [ABSTRACT FROM AUTHOR]

The high acceptance di-electron spectrometer at the GSI, Darmstadt, Germany, heavy-ion synchrotron Schwerionen Synchrotron is a high-resolution second-generation detector system for lepton pair spectroscopy. Its low-mass tracking system consists of two pairs of planes of trapezoidally shaped multiwire drift chambers, installed on either side of a superconducting toroidal magnet. This paper summarizes our experience with the construction and in-beam operation of the six large-area chambers produced by Forschungszentrum Rossendorf. Studies on creeping of aluminum wires over a period of three years are presented. In addition, the observation of the growth of filaments with various shapes and sizes in one of the chambers used in-beam will be discussed in detail. [ABSTRACT FROM AUTHOR]

Focuses on a study which examined the relationship between position and drift time in a cylindrical-type drift chamber. Description of the chamber with backgammon-shaped cathode pad; Construction of the chamber; Conclusion.

Presents a study on a digital time-measurement readout chip (DTMROC) which performs the signal processing, timing and data collection functions for proportional drift tube chambers. Description of DTMROC; Design and verification of DTMROC; Conclusion.

The readout and data acquisition systems designed for a first prototype of liquid xenon position sensitive gamma ray detector for Positron Emission Tomography is described. The problem of measurement of the gamma ray energy in the gridless multiwire ionisation chamber is considered. A previously suggested drift time based correction algorithm, allowing correction of the amplitude spectra for the contribution of positive ions, is experimentally tested. First ionisation spectra, with an energy resolution of 15-17%, are presented. A pulse shape discrimination method for rejecting the induction cross-talk between the wires, improving energy resolution and allowing the unambiguous identification of Compton scattered events in the detector, is described [ABSTRACT FROM PUBLISHER]

Large linear silicon drift detectors have been developed and are in production for use in several experiments. Recently 15 detectors were used as a tracking device in BNL-AGS heavy ion experiment (E896). The detectors were successfully operated in a 6.2 T magnetic field. The behavior of the detectors, such as drift uniformity, resolution, and charge collection efficiency are presented. The effect of the environment on the detector performance is discussed. Some results from the experimental run are presented. The detectors performed well in an experimental environmental. This is the first tracking application of these detectors [ABSTRACT FROM PUBLISHER]

Presents a study which described the drift chamber electronics for the BaBar detector. Design requirements; Electronics design; Performance; Conclusions.

Presents information on a study on the development of Binary Link Tracker Module for the B...B... Level 1 Drift Chamber trigger system. Drift Chamber input and track segment finding; Binary link tracker module.

Presents information on a study on the development of transistor full custom integrated circuit for the readout of drift chamber signals. Functional description; Signal flow; Summary.

Presents information on a study which discussed the continuously live image processor for drift chamber track segment triggering. Description of the track segment finder (TSF); Details on the TSF algorithm; Implementation of algorithms in hardware; Design methodology; Test results.

Focuses on the development of a Time-to-Digital-Converter (TDC) very-large-scale-integration (VLSI) TMC-PHX1 chip for the PHENIX drift chamber. What the chip contains; Details on the development of the chip; Reference to the PHENIX online system; Importance of frontend electronics; Specifications of the chip.

Describes TGLD, a charge readout chip designed for the PHENIX Pad Chamber (PC) subsystem at the Brookhaven National Laboratory's Relativistic Heavy Ion Collider in Upton, New York. High channel density of the chip; What the chip comprises of; Description of a typical PC front-end electronic channel; What the TGLD is designed for; Reasons for the design of the PC charge sensitive preamplifier.