Advanced Technology and Particle Physics

PREFACE.

CONTENTS.

The Alpha Magnetic Spectrometer (AMS) is a state of the art detector for the extraterrestrial study of matter, antimatter and missing matter. During the STS-91 precursor flight in may 1998 AMS collected nearly 100 millions of Cosmic Rays on Low Earth Orbit, measuring with high accuracy their composition. We present results on the flux of proton, electron, positron and helium. Analyisis of the under cutoff spectra indicates the existence of a new type of belts of energetic trapped particles characterized by a dominance of positrons versus electrons.

The objective of the HYPER project is to use the very high sensitivity of the atomic interferometry in space for research in fundamental physics This project is sustained by many scientists in the atomic physics community¹ and by ESA. After a short introduction, the second part will describe the recent development in atom interferometry. The third part is dedicated to the description of the mapping of the Lense-Thirring effect with an atomic gyroscope.

The Gamma-ray Large Area Space Telescope (GLAST) is an international space mission that will study the cosmos in the energy range 10 KeV – 300 GeV, the upper end of which is one of the last poorly observed regions of the celestial electromagnetic spectrum to be explored. GLAST will have an imaging gamma-ray telescope vastly more capable than instruments flown previously. The main instrument, the Large Area Telescope (LAT), will have superior area, angular resolution, field of view, and dead time that together will provide a factor of 60 or more advance in sensitivity, and capability for the study of transient phenomena.

The PAMELA experiment consists of a magnetic spectrometer, a transition radiation detector, an electromagnetic imaging calorimeter with a shower-tail catcher and a scintillator-based time-of-flight system. It will be launched late 2002 / early 2003. The spectrometer is surrounded by a scintillator-based anticoincidence system consisting of four lateral and one top anticounter which will help in discriminating against out-of-acceptance triggers. A simulation study has been made to determine how backscattering from the calorimeter affects the capability to reject background events.

Exploiting the Earth Atmosphere as a giant detector for the incoming extraterrestrial flux of High Energy Cosmic Rays and Cosmic Neutrinos, the mission "EUSO-Extreme Universe Space Observatory" is devoted to the exploration of the domain of the highest energy processes occurring in the Universe up to its accessible boundaries. The observable is provided by the Air Nitrogen fluorescence light emitted in the UV band 300 – 400 nm by the Extensive Air Showers produced by the cascading processes of the Primary C.R. Particles interacting with the Atmosphere. The EUSO telescope is based on a double Fresnel lens optics (diameter 2.5 m) coupled to an highly pixelized focal surface composed by multianode PMTs; the image at the Earth surface is detailed at 1 Km² over a total of several hundred thousand of Km². EUSO will fly on the International Space Station accommodated as External Payload of the European Space Agency Columbus module. The mission is scheduled to last 3 years, with the start of operations foreseen for 2007/8. The expectations are of a collection rate of a thousand events/year for Cosmic Rays at E > 10²⁰ eV together with tens/hundreds Cosmic Neutrinos at energy above about 4 × 10¹⁹ eV. EUSO is the result of the collaborative effort of several Institutions in Europe, Japan and USA and it is conceived within the science program sponsored by various Space Agencies coordinated by ESA.

The Cosmic Rays (hereafter CR) flux we can measure near the Earth is the result of a complex trajectory inside the geomagnetic field. On one side this acts like a shield for low energy primary CR, on the other side middle and high energy CR are focused and driven into preferential directions to reach the Earth. Excluding any kind of energy loss we can say that the energy spectrum in the solar cavity is essentially the same we measure at the Earth, but the magnetic field effect is to transform a (mostly) isotropic flux in a highly asymmetric one. AMS detector on board of the Space Shuttle in June 1998 has observed primary CR mixed with isotropic secondary quasi-trapped in the Earth magnetic field at low (400 km) altitude and over a large Earth surface (80%). We have developed a code to reconstruct the path (both forward and back in time) of CR inside the magnetosphere (hereafter mags). We realized a complete simulation of the primary CR flux seen by AMS in 1998. In this way we will obtain a relation between the input directions of primary CR outside the mags, and the observed (AMS data) directions. This transfer function F (R, ϑ, φ) is related to the rigidity R of the particle, and to the detecting position.

The Time-of-Flight (TOF) system of the AMS detector gives the fast trigger to the read out electronics and measures velocity, direction and charge of the crossing particles. The new version of the detector (called AMS-02) will be installed on the International Space Station on March 2004. The fringing field of the AMS-02 superconducting magnet is 1.0 ÷ 2.5 kG where the photomultiplers (PM) are installed. In order to be able to operate with this residual field, a new type of PM was chosen and the mechanical design was constrained by requiring to minimize the angle between the magnetic field vector and the PM axis. Due to strong field and to the curved light guides, the time resolution will be 150 ÷ 180 ps, while the new electronics will allow for a better charge measurement.

The AMS magnetic spectrometer will be installed on the International Space Station ISS to measure the properties of cosmic rays in the range of 1 to 1000 GeV during a mission of three years. A Transition Radiation Detector is used in combination with an electromagnetic calorimeter to reach a rejection of 10^-6 protons against positrons up to an energy of 300 GeV. This allows to search for cosmic cold dark matter through their decay products.

The T600 module is the first step of the ICARUS scientific program towards the construction of large liquid argon (LAr) masses (several kilotons) into the underground Gran Sasso Laboratory to study items of interest of the non-accelerator physics. The ICARUS LAr Time Projection Chamber provides a high resolution three-dimensional reconstruction of the ionising events that take place inside the sensitive volume. During the year 2001, after the completion of the first T600 half-module construction in the INFN laboratory in Pavia (Italy), the ICARUS Collaboration has accomplished a technical run of the detector collecting a large amount of data of cosmic ray interactions in LAr, in order to tune all the relevant detector parameters before the T600 physics run in the Gran Sasso Laboratory. Here we present the T600 main characteristics and the results of the Pavia test run.

The MONOLITH (Massive Observatory for Neutrino Oscillation or LImits on THeir existence) project is a proposal¹ for an experiment to be installed in the Gran Sasso underground laboratory to study atmospheric neutrino oscillations with a massive magnetized iron tracking calorimeter. The main purpose is to confirm the existence of atmospheric neutrino oscillations through the explicit observation of the first oscillation minimum in ν_μ disappearance. The MONOLITH detector has been designed in order to discriminate among different oscillation modes and to accurately measure the oscillation parameters in a range that completely covers the Super-Kamiokande allowed region. Other measurements include studies of matter effects, the NC up down ratio, the ratio, the study of cosmic ray muons in the multi-TeV energy region, and auxiliary measurements from the CERN to Gran Sasso neutrino beam.

The MAGIC Collaboration is building an imaging Čerenkov telescope at La Palma site (2200 m a.s.l.), in the Canary Islands, to observe gamma rays in the hundred-GeV region. The MAGIC telescope, with its reflecting parabolic dish, 17 m in diameter, and a two-level pattern trigger designed to cope with severe trigger rates, is the Čerenkov telescope with the lowest envisaged energy threshold. Due to its lightweight alto-azimuthal mounting, MAGIC can be repositioned in less than 30 seconds, becoming the only detector, with an adequate effective area, capable to observe GRB phenomena above 30 GeV.

MAGIC telescope is characterised by a 30 GeV energy threshold and a sensitivity of 6×l0^-11 cm^-2s^-1 for a 5σ-detection in 50-hours of observation. In this report, some future scientific goals for MAGIC will be highlighted and the technical development for the main elements of the telescope will be detailed. Special emphasis will be given to the construction of the individual metallic mirrors which form the reflecting surface and the development of the fast pattern-recognition trigger.

New developments of photodetectors for the lake Baikal neutrino experiment are described. Some test results of photodetectors at the lake Baikal are presented.

The PICASSO cold dark matter (CDM) detector is based on the phase transition produced by nuclear recoils in room temperature superheated liquids, induced by CDM particles, such as neutralinos predicted by supersymmetric models. Large-mass superheated droplet detectors have been built for the first time. We review their properties and operation. Simulations performed to understand the detector response are presented, briefly. Signal definition and analysis are described together with possible sources of acoustic background, with their frequency signatures, and eventual elimination. The PICASSO innovative droplet detectors for CDM search will allow the quantitative study of one of the main questions of modern physics.

The Gamma Ray Large Area Space Telescope is a high energy gamma-ray astronomy mission planned for launch in 2006. A Large Area Telescope is proposed to make observations of gamma ray sources in the 20 MeV ÷TeV energy range. A detector for space application should demonstrate satisfactory performance in the expected mission phase by appropriate analysis and tests. Following NASA requirements, we have defined a test plan to qualify and accept for workmanship the tracker trays. Thermal and dynamic tests have been performed on tray prototypes: their results will be presented.

The status of silicon strip detectors which were presented at the 7th International Conference on Advanced Technology and Particle Physics is reviewed.

The DØ collaboration has begun designing a new large scale silicon strip tracking system for the DØ detector for Run2b of the Fermilab Tevatron collider, which will deliver an integrated luminosity in excess of 15 fb^-1 to the experiment. The current design of the replacement detector will be presented with emphasis on those issues that drive the design. The tracker will employ about 2200 single sided silicon sensors. Detector readout will utilize the SVX4 chip that is currently being designed for the CDF and DØ Run2b upgrades.

We discribe the production, installation and commissioning of the new 792,576 channel D0 Silicon Microstrip Tracker to be used for the 2 fb^-1 of the Run IIa at the Tevatron.

The CDFII silicon tracking system, SVX, for Run II of the Fermilab Tevatron has up to 8 cylindricals layers with average radii spanning from ~(1.5 to 28.7) cm, and lengths ranging from ~(90 to 200) cm for a total active-area of ~6 m² and ~ 7.2 × 10⁵ readout channels. SVX will improve the CDFII acceptance and efficiency for both B and high-Pt physics dependent upon b-tagging. Along with the description of the SVX we report some alignment survey data from the SVX assembly phase and the actual status of the alignment as it results from the offline data analysis. The problems encountered are also reviewed.

The Silicon Vertex Tracker (SVT) is the new trigger processor which reconstructs 2-D tracks with high speed and accuracy at the level 2 trigger of the CDFII experiment. SVT allows tagging events with secondary vertices and therefore enhances the CDFII B-physics capability. SVT has been fully assembled and operational since the beginning of Tevatron RunII in April 2001. In this paper we briefly review the SVT design and physics motivation and then describe its performance during the early phase of CDF RunII.

The CDF-II silicon detector has been partially commissioned and used for taking preliminary physics data. This paper is a report on commissioning and initial operations of the 5.8m² silicon detector. This experience can be useful to the large silicon systems that are presently under construction.

The AMS (Alpha Magnetic Spectrometer) experiment is a detector designed to search for antimatter and dark matter. A first version, AMS1, has flown on June 1998, on board of the Shuttle Discovery, during the STS91 mission. The complete detector, AMS2, will be installed on the International Space Station in 2004 and it is foreseen to operate for a period of three years.

We report on AMS tracker alignment control in space using artificial laser produced straight tracks (flight data AMS-01, laboratory tests AMS-02) as well as precisely measured high momentum cosmics tracks.

The BABAR Silicon Vertex Tracker (SVT) consists of five layers of double sided, AC coupled silicon strip detectors. The detectors are readout with a custom IC, capable of simultaneous acquisition, digitization and reduction of data. The SVT is an essential part BABAR, and is able to reconstruct B meson decay vertices with a precision sufficient to measure time-dependent CP violating asymmetries at the PEP-II asymmetric e⁺e^- collider. The BABAR SVT has been taking colliding beam data since May 1999. This report will give an overview of the SVT, with emphasis on its running performance.

The HERA-B experiment at DESY is a large acceptance fixed-target spectrometer using a silicon vertex detector, an inner GEM MSGC detector and an outer large volume honeycomb drift chamber for track reconstruction. The detectors are operated in a radiation environment comparable to LHC conditions. The tracking detectors had been finished at the beginning of year 2000 and have been successfully operated. They represent the worlds largest operated GEM MSGC system and the so far largest drift chamber system for high-rate application. We report on the detector operation, and summarize the performances achieved. We present the performance of the track finding algorithm and report on the reconstruction performance for the year 2000 data.

For the luminosity upgrade at the HERA ep collider, the ZEUS experiment has designed, constructed and recently installed a Silicon Microvertex Detector. The design of the detector and the performance of prototypes are discussed. The readout chain, the adopted online and control solutions as well as the integration within the existing trigger and acquisition systems of the experiment are presented. Tests with the full detector prior to installation and the first experience using cosmic rays in the final environment are reported.

A substantial portion of the RunIIa silicon detectors of the CDF experiment will not perform adequately for the duration of Run IIb (15 fb^-1) because of radiation damage. The Silicon Vertex Detector (SVX-II) and Layer 00 will be fully replaced at the end of Run IIa. The Run IIb silicon tracker has a baseline design that safely achieves the required radiation tolerance by using single sided sensors that are actively cooled. The new Run IIb castellated layout contains more silicon surface area and has a more uniform radial distribution. It minimizes the number of hybrid and sensor varieties providing quick construction and assembly. The total mass in the tracking volume is reduced by eliminating unnecessary the passive material from the CDF volume.

BTeV is a collider experiment approved to run at the Tevatron at Fermilab. The experiment will conduct precision studies of heavy flavor decays, with particular emphasis on CP violation, flavor oscillations and rare decays. One of its unique features is a state of the art pixel detector system, designed to provide accurate measurements of the decay vertices of heavy flavored hadrons that can be used in the first level trigger. This will insure the ability to perform precision study of a variety of final states and to search for rare phenomena with very high efficiency. The main design features of the pixel vertex detector are reviewed.

The increasing need of high performance flavour tagging capabilities in particle physics experiments has triggered the development of a novel - fully integrated - silicon pixel detector, called Monolithic Active Pixel Sensor. The first MAPS prototypes adapted to the detection of minimum ionising particles (mip) were designed and fabricated in standard CMOS technology. Their first tests demonstrate that the sensors detect mips with high signal-to-noise ratio, detection efficiency close to 100% and provide excellent spatial resolution. The main aspects of these results are summarised in this paper, together with preliminary results on the radiation hardness of MAPS. An outlook on the R&D started to adapt and integrate the sensors for future vertex detectors is also provided.

The ATLAS Pixel detector is based on a set of radiation-hard electronics chips able to resist a dose of 500kGy. The implementation of these chips in the DMILL technology did not give the expected results. Re-design of the radiation-hard chips in DeepSubMicron technology is ongoing, but has implied a one and a half year delay in an already tight schedule. Major layout changes have therefore been necessary to allow installation of the ATLAS pixel detector at LHC start-up.

This paper illustrates the status of the ATLAS pixel project, the motivations for the new layout, the way this should be implemented and the prototype fabrication and testing.

The Semiconductor Tracker (SCT) is based on a large area of silicon microstrip sensors inside the ATLAS inner detector system. About 4100 detector modules must be assembled and placed on 4 barrel cylinders and 18 forward disks. Most of the modules are composed of 4 single sided detectors mounted back to back with 40 mrad rotation allowing the reconstruction in the other direction. The sensors are read-out by a copper/Kapton multilayer hybrid which holds 12 binary read-out ASICs. The commands and data are transmitted via optical fibers. The SCT is designed to operate 10 years in the LHC and, all the active and passive module components must survive a high radiation level. A description and a current status of the silicon detectors and the SCT modules will be given. The electrical performances of the prototype modules will also be discussed.

The CMS experiment at the Large Hadron Collider will have a large Silicon Strip Tracker. The status of the project is here reviewed. The detector layout is presented, and some of the expected performances are discussed. The problem of radiation damage of silicon sensor is addressed, and the final choice for the silicon technology is shown. The construction of such a large scale detector requires an adequate organization, which is here discussed. Finally the present status of the Silicon Strip Tracker construction is presented.

In December 1999 the CMS Tracker Collaboration decided to make its tracking system entirely based on silicon detectors¹. The new tracker layout requires the assembly of about 17000 silicon strip detector modules, each one composed of silicon sensors and readout hybrid glued onto a carbon fibre frame. To guarantee the assembly of such a large quantity of modules with high quality but reduced manpower, an automated system has been developed at CERN. The system setup is based on a robotic machine, Aerotech AGS 10000 Cartesian Gantry Positioning System, equipped with high-precision positioning motors. The design of such automated silicon module assembly system is described and the performance in terms of positioning precision and assembly rate is shown.

The tracker of CMS^1,2 will fully consist of silicon micro-strip and pixel sensors. Building a detector with 210 m²sensor surface in about 3 years requires a tightly controlled construction schedule. All different aspects of the production are exercised within a pre-production of 200 modules (Milestone 200) to identify and eliminate possible bottlenecks and to test the complete electronic chain. The quality, process stability and radiation hardness of the silicon sensors will be permanently monitored. Automatic assembly procedure and industrial bonding machines will guarantee a fast and reliable construction. All modules will be tested for signal, noise and pedestals at room temperature and operation temperature of -10°C.

Quality assurance of the Milestone 200 sensors and modules including irradiation and stability tests are presented.

CMS silicon microstrip detectors of different types equipped with the APV readout chips have been exposed to a high intensity 350 MeV/c pion beam. We study the performance of irradiated and non-irradiated silicon sensors as well as the readout chip behavior. Maximum signal to noise for the irradiated oxygenated sensor has reached 15 in deconvolution mode.

The innermost layers of the CMS tracking system will consist of pixel detectors. They will allow pattern recognition in the high track density and will be used as vertex detector. An overview of the system and a status report on the different components will be presented. Emphasis will be given to the latest developments in 2001: The first submission of a full-size radiation-hard readout chip and the latest sensor prototyping.

A fabrication technology has been developed at ITC-irst (Trento, Italy) for the realisation of silicon microstrip detectors with integrated front-end electronics, to be used in high-energy physics and space experiments as well as in medical/industrial imaging applications. The main technological issues are addressed, and experimental results from the electrical characterisation of the first prototype batch are reported, showing that good quality transistors are obtained within the proposed technology while preserving the basic detector parameters.

CVD-diamond detectors operational in various heavy-ion experiments at GSI are described. The results shown demonstrate convincingly the suitability of such detectors for a variety of tasks, where classical well known detectors fail. New applications are introduced, which are being recently developed for the use in measurements of minimum-ionizing particles.

P-type ZnO layers with a hole mobility about 23 cm²/(V s), and a hole concentration about 10¹⁵ cm^-3 were grown by means of radical-beam gettering epitaxy (the annealing of n-ZnO single crystals in atomic oxygen flux). The effect of native defects on the photoluminescence spectra of the layers was studied. The dominant bands in the spectra peaked at 370.2 and 400 nm. These bands were attributed to the annihilation of exciton localised on neutral V_zn and to electron transitions from the conduction band to singly positively charged V_zn correspondingly. The effect of annealing in atomic nitrogen flux of p-CaN:Mg films on their photoluminescence spectra and on the value of their conductivity were studied. Such annealing leads to appearance of a number of emission bands that peaked at 404.9, 390.8 and 378.9 nm and increases hole concentration from 5 × 10¹⁵ to 5 × 10¹⁶ cm^-3, and the hole mobility from 120 to 150 cm²/(V s). The n-ZnO – p-GaN:Mg electroluminescence heterostructures were obtained. Their spectrum contains bands in the excitonic region of GaN at the wavelength 360.2 nm and in the edge region at wavelengths 378.9 and 390.8 nm.

For the small–area tracking of the COMPASS experiment, GEM detectors with an active area of 31 × 31 cm² are employed. These detectors use three cascaded GEM foils with asymmetric voltage sharing and Ar:CO₂ (70/30) as detector gas. The GEMs have a non-uniformity in gain of less than ±15% and achieve an efficiency of 99.0 ± 0.1% and a spatial resolution of 46 ± 3 μm for minimum–ionizing particles at nominal gain of ~ 8000. The narrow charge correlation (σ_rat< 0.1) between the orthogonal coordinates of the 2D projective readout improves the reconstruction capability for multiple hits. High rate tolerance and low discharge probability make the GEM detectors well suited for operation in intense muon and hadron beams.

The readout chain of the GEM and the silicon detectors of the COMPASS experiment at CERN is based on the APV25 frontend chip. The system utilizes optical fibers for data transmission and is designed to stand high event rates. Using the Multi readout mode of the APV 25, giving three samples per event, a very good time resolution of the detectors can be achieved. The high trigger rates require an efficient zero suppression algorithm. The data sparsification that is performed in hardware features an advanced common mode noise correction utilizing a combination of averaging and histogramming.

The Pre–Shower detector system of the HADES spectrometer is applied to electron identification with emphasis on fast hadron rejection at forward angles. The detector is operated in the self–quenching streamer mode (SQS) to simplify on-line recognition of electromagnetic showers. Stable electronics at low noise guarantee robust pattern recognition through the experimental runs. The construction and performance of the detector is presented.

The ALICE TPC is a conventional TPC based on experience with previous TPCs used in heavy ion beams. However, the unpreceeded high particle multiplicities at LHC Pb+Pb collision has led in detail to many innovations in its design and construction.

Main cathode strip chambers (CSC) data analysis tasks are: calibration, reconstruction of the transmission function (transformation of CSC readout information to the coordinate of particle), track finding, optimal track parameters estimation and alignment. Methods for solution of these tasks (excepting calibration) are described. The influence of CSC geometrical parameters, sampling time and a number of signal readout samples, uncorrelated background, overflows and magnetic field to the spatial resolution are analysed. Proposed methods and algorithms are useful for the data analysis as well as for detector optimisation.

In complex detectors for high energy and nuclear physics experiments a high number of multi-cell gas detectors (in the range of thousands) are often used. In such cases a parallel, reliable, automatic, continuous monitoring gas system has to be built and operated in order to control and check the operational parameters (gas mixture composition, pressure, flux, gas losses…) that affect the detector performances and safety requirements. FINUDA is an experiment employing a large gas multi-cell detector and the gas system built and operated to flow its straw tubes is described. Straw tubes are used in FINUDA for charged particle tracking. The total number of tubes is 2424 (~ 2.5 m long, 1.5 cm diameter) with a gas volume of about 0.5 l each. They are mounted on three super layers (each one composed by two staggered layers) one axial and two stereo. The straws are made of thin aluminized mylar and each one is flown individually. The gas system has been designed to offer modularity, parallel layout, immunity from individual straws leakage, safety and remote control. An automatic gas bottle inversion system has also been implemented and will be described.

This article describes the present status and physics prospects for Run 2 at the Fermilab Tevatron accelerator. The accelerator complex and both the collider detectors, CDF and D0, have completed extensive upgrades resulting in a significant increase in luminosity and physics capability.

An overview of the detectors foreseen for an e⁺e^- Linear Collider is presented. The Physics program of such a type of machines requires high precision detectors. The solutions proposed for the European project (TESLA) are presented in detail with short recalls to the alternative solutions proposed in the other regions.

ATLAS is a general purpose proton-proton experiment at the Large Hadron Collider (LHC) at CERN. The primary goal of the experiment is to operate at high luminosity (10³⁴ cm^-2 s^-1) with a detector that provides as many event signatures as possible. The quality of the muon measurement is insured by a system of three large superconducting air-core toroid magnets, precision tracking detectors with 80 μm intrinsic resolution and a dedicated trigger system. The ATLAS muon system is now in the construction phase. The main features of the muon spectrometer are presented in this paper together with the status of the chamber mass production.

We present the status and the Progress Report of the U.S. Muon End Cap system.

The MACRO limited streamer tubes can be operated in drift mode by using the TDCs included in the QTP system. In this way a considerable improvement in the space resolution is obtained, allowing the analysis of muon tracks in terms of multiple scattering effects and the energy estimates of muons crossing the detector. We present the results of two dedicated tests, performed at CERN PS-T9 and SPS-X7 beams, to provide a full check of the electronics and to exploit the feasibility of the analysis. Using a neural network, we are able to estimate the muon energies up to E_μ ≃ 40 GeV. The test beam data provide then an absolute energy calibration, which allows to apply the method to the MACRO data.

A functional implementation of a vertical slice of the ATLAS Data Acquisition has been exploited in the past two years as a DAQ system for testbeam and lab test with satisfactory results. Here the setup descriptions and figures of merit are reported.

Cathode strip chamber (CSC) was chosen as the baseline detector of the CMS Endcap Muon System. First forward muon station ME1/1, located in the solenoid magnetic field, is the key station because it should provide precise matching between Muon System and Inner Tracker. The ME1/1 CSC spatial resolution must be about 75 μm per station to achieve required muon momentum resolution and timing resolution of few ns for bunch crossing identification. Uncorrelated background rate is 1 kHz/cm² or 100kHz per readout channel. The solenoid magnetic field is up to 4 T. CSC design is described. R&D results of the CSC performance study are presented: spatial resolution, timing resolution, rate capability, track reconstruction efficiency, influence magnetic field on CSC parameters. Test of many CSC prototypes demonstrated that ME1/1 CSC performance meets CMS requirements.

The Run 2 DØ muon detector at the Fermilab Tevatron has three subsystems: Proportional Drift Tubes (PDTs), Mini-Drift Tubes (MDTs) and trigger scintillation counters. The PDTs were used in the 1992-1996 data taking run and provide tracking coverage for pseudorapidity | η | ≤ 1.0. The forward muon tracking system, new for Run II, uses planes of mini-drift tubes and extends muon detection to | η | = 2.0. Scintillation counters are used for triggering and for cosmic muon and accelerator backgrounds rejection. Toroidal magnets and special shielding complete the muon system. All subsystems interact with 3 levels of triggers. Level 1 generates trigger information synchronously with the beam crossing. Level 2 operates asynchronously with a maximum decision time of 0.1msec. All three muon detector subsystems use a common readout system based on a 16-bit fixed point digital signal processor, which buffers the data from the front-end, re-formats the data if accepted by Level 2 and sends it to the Level 3 trigger system, which is a farm of Linux workstations running software trigger filters. Muon triggers accepted by Level 3 are written to tape for offline reconstruction.

The goals of high energy physicists for the next decade require new designs for the online systems of collider experiments. We describe the new DØ Central Tracker Trigger (CTT) System, which makes heavy use of field programmable gate arrays (FPGA) and digital signal processors (DSP) to allow the system to cope with the greatly increased data rate anticipated at the Fermilab Tevatron. We describe briefly how the CTT system meets the physics goals of the collaboration.

The strict requirements in Cherenkov angle resolution combined with the size and complexity of the LHCb RICH2 detector will pose a challenge in the quality and alignment of the mirrors. There are 28 spherical and 20 planar mirror segments in each half of RICH2, and the required Cherenkov angle resolution is below 0.6 mrad. We have studied extensively the mirror misalignment effect on Cherenkov angle resolution and particle identification performance, and to what extent alignment with data can compensate for mirror misalignment. Our results show that the initial mirror alignment must be better than 1 mrad to achieve a negligible effect of the alignment on the total Cherenkov angle resolution.

The muon Spectrometer of the ATLAS experiment is instrumented with precision tracking chambers made of layers of drift tubes assembled together with very high mechanical positioning accuracy. The chambers are arranged in three stations (inner, middle and outer). The middle station in between the coils of the toroid magnet in the barrel is built at Laboratori Nazionali di Frascati of INFN, where methods for the construction of the drift tubes and the precision assembly of the chambers have been developed. These methods aim at both achieving the required performance of the detector as well as a high level of automation in the serial production of the chambers. The construction methods and the first results of the production are presented.

This paper presents the Conditions Database, a C++ library (currently based on Objectivity/DB) developed by the Database group of the CERN IT Division, for use in the current and future (LHC) experiments at CERN. The package can be used to manage conditions data of a detector into a database; these are the conditions that vary with time and are necessary for the reconstruction and analysis of raw data. The library provides an abstract interface, independent of the underlying DBMS, which means that moving from an implementation based on a certain DBMS to another one would have very little impact on the user code.

No abstract received.

The Compact Muon Solenoid (CMS) is one of two ominpurpose experiments to be constructed at the Large Hadron Collider (LHC) at CERN. CMS incorporates a precision Electromagnetic Calorimeter which will be the largest crystal calorimeter ever constructed. The harsh environment at the LHC places stringent demands on the detector components. Following an extensive development period production of parts for the CMS ECAL is under way. An overview of the current project status is presented including results from recent prototypes and quality control tests on production components.

The ATLAS liquid argon front-end system will instrument 190000 calorimeter channels, providing low-noise, highly-accurate digital signals to the read-out drivers (RODs) and to the second-level trigger, as well as fast analog outputs to the first-level (LVL1) trigger. The bipolar-shaped ionization signals are sampled at the 40 MHz LHC frequency and temporarily stored into analog memory, during the fixed 2.5 μs LVL1 latency. For each LVL1 trigger, a configurable number of samples (typically 5) are digitized and sent to the ROD via optical links.

Most of the digital components have been redesigned to comply with radiation tolerance requirements. The logic has been implemented in DMILL and/or 0.25 μm ASICs, and feature error-correcting circuitry for protection against single-event upsets. Radiation tolerance studies of the ASICs have been performed using a high-intensity proton beam. Radiation results are presented.

A new tungsten/scintillating fiber spaghetti calorimeter was constructed for the ZEUS detector at the electron-proton collider HERA. The calorimeter will be located 5.3 m from the interaction point, inside one of the HERA quadrupole magnets. It will detect electrons coming directly from the interaction point under very small angles. Test beam measurements with the fully assembled detector show an energy resolution of and a position reconstruction resolution of 0.93 × 0.51 mm².

The ATLAS collaboration will start to collect data at the LHC proton–proton collider in 2006. It has chosen a liquid argon-lead sampling electromagnetic calorimeter using the accordion geometry. In 1999 and 2000, barrel and end-cap prototype modules have been tested under electron beams at CERN. Detailled results from these tests are shown.

In this paper, we provide a description and status report on the barrel hadronic calorimeter for the ATLAS detector at the CERN Large Hadron Collider. We describe measurements taken with prototype and initial modules of the calorimeter, in particular those involving muon energy loss.

The CMS Electromagnetic Calorimeter (ECAL) will be made of almost 80000 lead tungstate crystals. The barrel part will be composed of 36 supermodules with 1700 crystals each, divided in 4 modules. This paper reports on the construction of the first Module, called Mod #0', that will be tested under beam conditions. The optimum quality of the crystals that form Mod #0' together with the light collection uniformization techniques applied and the results obtained will be described. In addition, different gluing techniques and results for the 400 Mod #0' crystals will be also reported in this paper. Other aspects, such as the mounting sequence that follows the gluing of the crystals to the photodetectors or the thermal regulation of the module will be also discussed.

For the half completed ANI sampling calorimeter (1600 m² detection area, 6 concrete absorber layers of 1 m thickness each) at Mount Aragats, Armenia, a cheap and efficient active detector element is needed. A new concept for such a detector element and first results from a reduced size prototype are presented.

The CMS Hadron Calorimeter is designed to measure hadron jets, single hadrons and single μ's. The Central Barrel and the two End Caps, made of brass and scintillators cover the | η | range of 0.0 to 3.0. The two Forward Calorimeters made of iron and quartz fibers extend the | η | range to 5.0. Scintillators are also placed outside of the magnet coil, within the muon system to measure the energy leakage from the Central Barrel. The construction of the calorimeter is about 50% complete. Several design changes were made to simplify the calorimeter and reduce the cost. The longitudinal segmentation of the central barrel and end caps was reduced by one unit. The quartz fiber diameter was doubled from 300 to 600 microns. Improvements were made to the Hybrid Photodetectors (HPD) and various other components. The special purpose ADC (QIE) and other electronics are in prototype stage.

An overview is given of the ATLAS liquid argon calorimeter system. The liquid argon system uses several different design technologies in different pseudorapidity regions of the detector. We discuss how the design goals have led to each of these technology choices. For each of the systems we describe the mechanical structure, the measured performance, and the status of construction.

A description of ATLAS liquid Argon Hadronic Endcap Calorimeter (HEC) will be given followed by a report on its construction. The plans for assembly of the HEC and its insertion into the endcap cryostat will be briefly discussed. In addition, a description of the recent test beam setup where HEC modules were exposed to beams of electrons, muons and pions in the energy range 6GeV < E < 200GeV at the CERN SPS, will be presented. The key test beam results will be reported. A brief progress report on the HEC construction and plans for future joint test beam studies will be given in the conclusion.

No abstract received.

A review is presented of some recent R&D of inorganic-scintillators for medical imaging, in particular fluoroscopy, X-ray CT and PET.

The new radiotherapy techniques require new detectors to monitor and measure the clinical field. The Intensity Modulated Radiation Therapy (IMRT) techniques like step and shoot, sliding window, dynamic wedge or scanning beam add the time variable to the treatment field. In this case the water phantom with a single ionization chamber moving inside the field needs very long measurement time. Linear arrays of ionization chambers or diodes measure the field only along a line. 2D detectors like radiographic or gafchromic film are not suitable to be used as on line detectors. We have developed, built and tested an ionization chamber segmented in pixels that measure the dose in a plane at several points. Every channel has a dedicated electronic chain that digitizes the collected charge and data from all the channels are sent to the computer that performs the data acquisition. One read out cycle is very fast allowing to measure in real time the fluency and the shape of the field. The chamber can be used in two different ways, as monitor chamber and as relative dosemeter. A description of the detector, the electronics, and test results with both photon and hadron beams will be reported.

The variety of available positron emission tomography (PET) radiotracers and the ability of providing quantitative estimates of radiotracer concentrations make PET an invaluable tool in the in-vivo investigation of biological processes. Mathematical descriptions of the processes under investigation are used to extract relevant kinetic parameters from the time course of radioactivity concentrations. Such kinetic parameters can provide a quantitative description of both, the characteristics of a particular process, and its changes due to various disease states.

The epithermal column of TAPIRO reactor has been characterized and in-phantom dose has been imaged, with the purpose of determining parameters and data whose knowledge will be of main importance for future experimentation regarding boron neutron capture therapy (BNCT). In-phantom measurements have been carried out mainly utilizing a recently developed method for absorbed dose imaging, based on gel-dosimeters. Gel-dosimeters have revealed to give significant support to thermal or epithermal neutron dosimetry: in fact, the modality of energy release in gel-dosimeters is very similar to that in tissue, and with proper adjustment of the isotopic composition of gel matrix, the various dose components are separated.

The ISOLDE facility at CERN is the world leading on On-Line Isotope Separator installation. The main aspects which makes ISOLDE produced radio-isotopes such valuable for use in bio-medical research are: the availability of exotic or uncommon radioisotopes, the high purity and the ion beam quality.

A short overview on research strategies, on experimental work and application of ISOLDE produced radionuclides used in the field of biomedicine over a period of more than 2 decades will be given. Special attention will be directed to the radio-lanthanides, because they can be seen as one single element providing the unique possibility to study systematically relationships between molecule parameters and a biological response without changes in the basic tracer molecule. Among those radionuclides we find any radiation properties we wish (single photon emission suitable for SPECT, positron emission suitable for positron emission tomography (PET), α-, β^-- and Auger electron emission. The radioactive isotopes obtained at ISOLDE are primary singly charged ions of 60 keV energy, very suitable for a new principle for a radionuclide generator system: the implantation type of the ⁸¹Rb/^81mKr-generator for in vivo use and useful for new labelling procedures.

No abstract received.

Over the years this conference has gained a solid reputation as an appropriate rostrum for illustrating new concepts in the relations between industry and the scientific world and for introducing new technologies to a large assistance of junior and more experienced scientists. In fact, from the very beginning the founders of this endeavour announced: "The conference is aimed for promoting contacts among scientists involved in particle and fundamental physics, among experimental physicists in other fields and representatives from industry." Facilities at the Conference are designed to fulfil the task: space and general facilities are offered to industry representatives to display their products. This year a more accessible and luminous space arrangement was made available to the exhibitors. At the same time two plenary sessions have been dedicated to selected speakers to illustrate new trends in Technology Transfer, analysis of environment affecting our community, examples of historical successes in the merging of science and industry. We have identified in "GRID" and in "E-Publishing" two major promising areas where our Community will play a prime role as "User" and it was of the general interest to have them illustrated by two personalities directly involved in their development. The flow of knowledge is of course more massive from "Industry" to "Science" than vice-versa, but "Science" to "Industry" move offers an intensive added value. The technology transfer concept with the "Patents" as fund raising tool proved less glorious than expected. Trademark, licensing agreement and " Patents" can assure intellectual properties. But patent is an issue to be used cautiously. Evidence exists that much more efficient transfer of "Science" knowledge to "Economy" is achieved by venture capital move and start-up companies. These two facets of the Technology Transfer business have been covered by Routti's and Bourgeois's lectures.There are two examples of Companies who moved recently into the areas of interest of our community (Hourdakis and Intrasoft) and the examples of an Industry historically committed to a strong R&D effort (SAES-Getters). Finally a case of involvement of industry in a "Big Science" project (CMS) completed the palette of the contributions to this Industry Section. The full set of transparencies of the lectures, are filed and made available at the conference site: http://hpl302.mib.infn.it/Conference2001.html.

We present the current three models: traditional, alternative, and subversive, with examples and realisations in various disciplines. We also present a short overview of the debate under way about self-publishing and the proposed methodology. We continue with a presentation of library procedures to take advantage of electronic publishing opportunities in terms of enlargement of the literature collections available to readers. In this perspective we discuss both internal library procedures and external licensing negotiation. Then we shall talk about the emergence of the E-book. We end with a presentation of the impact of electronic publishing within the new Web economy and discuss costs and benefits of the new publishing cycle.

In this paper we give the description of a project accomplished by a collaboration of researchers, engineers and managers from a Greek medium-size company Hourdakis Electronics S.A and the research laboratories CERN in Geneva and DEMOKRITOS in Athens. The project involved the production of 22 Input-Output DAQ electronic modules to be used for R&D purposes in the Compact Muon Solenoid experiment of LHC at CERN. This project can be considered a successful technology transfer.

The Trigger and Data Acquisition systems will play a key role in experiments at the Large Hadron Collider (LHC) currently under construction at CERN. At the LHC, with a beam-crossing frequency of 40 MHz, and a design luminosity of 10³⁴ cm^-2 s^-1, an average of 20 inelastic pp events will be produced per crossing. The CMS detector, with more than 10⁸ electronics channels, will produce ~1MB of zero-suppressed data per crossing, so that both the collision and the overall data rates are many orders of magnitude larger than the current goals of storing events at a rate of at data rates of respectively. The CMS Trigger and Data Acquisition System is designed to analyse the detector information at the full crossing rate and to select a maximum of 100 Hz of events to be stored for offline analysis.

QuarkNet is a national program that partners high school science teachers with particle physicists working in forefront experiments at the scientific frontier. These experiments are searching for answers to fundamental questions about the origin of mass and about the nature of symmetries that govern physical processes. QuarkNet's goals are to establish a lasting national community of researchers that includes high school teachers and students as well as physicists, to attract young students to careers in science and technology, to help develop scientific literacy in society, and to develop links between the high school classroom and experiments and techniques used to explore the scientific frontier.

The selected device for the ALICE Time-of-Flight is the Multigap Resistive Plate Chamber. This detector, consisting of a stack of glass plates, has a time resolution close to 50 ps. We discuss the principle of operation of this detector and present the latest results from the ongoing R&D program.

LHCb is an experiment for precise measurements of CP-violation in the decays of B mesons. Very good charged particle identification will be crucial for clean measurements of rare CP violating decays against an abundant background as well as for efficient kaon tagging. Thus LHCb employs two Ring Imaging Cherenkov (RICH) detectors to achieve K-π separation over a wide range of momenta. This paper presents the status of the LHCb RICH project. The requirements and the design of the detector are covered. The choices of the radiators and on R&D results for the photodetectors are reported. And the adopted solutions for the sub-components of the detector are discussed. Finally, the expected performance of the RICH detectors projected from full scale simulation based on R&D results is shown.

The particle identification capabilities of the HERA-B RICH are shown on the measured data from the latest run period. The detector has performed excellently since its installation in 1998. It is capable of efficient particle identification at high track multiplicities and high interaction rate of the HERA-B experiment.

Unambiguous kaon identification is needed for Hypernuclear High Resolution Spectroscopy Experiments in Hall A at Jefferson Lab. Due to the huge pion and proton background, TOF and Areogel threshold detectors are not sufficient. A proximity focusing CsI/freon RICH detector has been designed and built. The tests performed at CBRN showed that the performances are as good as expected. A dedicated CsI evaporation facility, togheter with an on line photocathode QE measurement for mapping out the entire photocathode, has been built and succesfully used.

The Silicon Transition Radiation Detector (Si-TRD) is a transition radiation detector based on the techonolgy of silicon microstrip detectors. Due to the relatively high ionization energy release in semiconductor material (a few hundred keV), silicon detectors have been used in conjunction with a magnetic field in order to separate the transition radiation X-rays from the radiating particles. A SiTRD prototype has been tested with an electron-pion beam at CERN-PS with momenta up to 3 GeV/c. The beam test results will be presented and compared with the predictions obtained from a full Monte Carlo simulation.

After a brief overview of the ALICE Transition Radiation Detector (TRD), we present results from tests of prototypes for this detector. By investigating the performance of various radiator materials we have established the components and the design of the final radiator. The pion rejection performance is presented for the momentum range 0.7–2 GeV/c, for different methods of analysis. The position reconstruction performance is investigated.

A novel design of a transition radiation detector based on silicon microstrip detectors is presented. Due to the relatively high ionization energy release in silicon (a few hundred keV), a magnetic field should be used to separate the radiating particle from transition radiation X-ray photons. The magnet bending power, strip-pitch, charge sharing, noise and front-end electronics have been carefully studied and optimised by means of a full Monte Carlo simulation of the silicon transition radiation detector. The particle identification capability allows the separation of hadrons or nuclei from electrons up to 40 GeV/c momentum.

Radio, optical and X-rays telescopes are improving our knowledge of deep space. All these telescopes detect electromagnetic radiation at various frequencies. But a different kind of radiation is generated in the deeper space; it is the gravitational one. Gravitational waves change the space-time metric. As a consequence, GW telescopes should detect an extremely small strain (h < 10^-21) of the geometry of a reference frame; if the frame has a reference dimension (L) of some kilometers, the deformation amplitude (ΔL = h × L) is limited to 10^-16 meters. Laser interferometers are the most suitable devices to make precise measurements of distances. Their resolution is limited by the laser wavelength (λ = 10^-6 meters) and by the light wave-shift detection capability (Δ Φ= 1 ppb). These theoretical limits are strongly degraded by different noise sources, which reduce the actual resolution by several orders of magnitude. Applied physicists and engineers are working together to overcome the technical problems that still keep the distance between theoretical and actual detectors' performances. Three large GW telescopes, based on the laser interferometric technology, are under commissioning in the USA (2) and Europe (1). They will become operatives in the next years, with sensitivity of the order of h = 10^-21, in the range between 10 Hz and a few kHz. Among the others, two characteristics are peculiar of the VIRGO interferometer: the high performance of the mirrors' seismic isolation system and the huge ultra high vacuum volume, that will result in the biggest UHV apparatus ever built all over Europe.

We report on the latest developments in position sensitive photon counting detectors based on microchannel plates. Substantial improvement of the spatial resolution was achieved with introduction of new readout technology, namely crossed strip (XS) anode, and corresponding processing electronics. The spatial resolution of XS readout appeared to be as small as ~3-4 μm FWHM. Reduction of the total detector gain (down to 10⁶ and potentially lower) without compromising the spatial accuracy allows detector operation at much higher local and global counting rates since the microchannel recharge time becomes smaller. Recent developments of novel microchannel plate technologies provide basis for substantial increase of the spectral sensitivity and quantum efficiency of MCP detectors. We have tested a number of new Silicon micromachined MCPs The new MCP technologies should allow deposition of completely new photocathode materials directly on the front surface of microchannel plates (opaque photocathodes). Opposite to standard glass MCPs new Silicon MCPs can sustain high temperatures (-800 C°) required for the photocathode deposition and activation processes.

The Sand-Glass Gas detector is a position-sensitive micro-pattern detector manufactured using printed circuit board technique. It consists of two kapton foils, copper-clad on both sides and perforated by a high density holes, kept in electrical contact, thus forming triple electrode structure. The structure is placed in a middle between two parallel, conductive planes. With a symmetric electric field in the holes of the structure all avalanche electrons are collected on the central electrode of the Sand-Glass holes. Signals are picked up independently on all three layers segmented into strips giving the possibility of 2-D positional information. The electrostatic field calculation and avalanche process simulation are presented. Results of the gas gain and energy resolution measurements in the gas mixtures Ar/iC₄H₁₀ (95%/5%) and Ar/CO₂ (87.8%/12.2%) with ⁵⁵Fe X-rays source are reported.

Silicon μ-cell Avalanche Photodiode operating in Geiger mode (APD_G) was used to detect light produced in scintillating fibers of 1 mm diameter by electrons from a ⁹⁰Sr-source and by α-particles from a ²³⁸Pu-source. This recently developed in mesa-technology square 1 mm² APD_G, consisting of 1370 μ-cells, has enhanced inter-cell optical isolation and individual quenching resistors. It showed at room temperature and low biasing voltages (45-47 V) very high gain (up to 10⁶), low dark counting rates (below 3 × 10⁵sec^-1) and high detection efficiency for photons of green light (> 35%). Basic characteristics - internal gain, dark counting rate and average number of detected photoelectrons as a function of bias voltage were measured.

A novel neutron detector based on the MICROMEGAS concept is presented. One of the applications of this detector is the determination of the high performance and characteristics (neutron beam profile,flux and energy resolution) of the new high-flux spallation neutron source, the neutron Time-Of-Flight facility (n_TOF) at CERN.

The DØ Detector, one of two large collider detectors at the Fermilab Tevatron, has recently completed a major upgrade and has just begun operating with the Main Injector. An integral part of the upgraded detector is an entirely redesigned inner tracking volume, which includes two new scintillator-based particle detection systems read out by visible light photon counters (VLPCs): a Scintillating Fiber Tracker, and a Central and Forward Preshower system. A general overview of the design and technology of these tracking elements, including a discussion of the cogent physics goals they are to address, will be presented.

The ARGO experiment is a full coverage air shower array consisting of a RPC carpet of size 100 × 100 m² being installed at the YBJ laboratory (4300 m a.s.l., Tibet, P.R. of China). Its main purpose is the study of gamma ray astrophysics in the energy range from 100 GeV to several TeV. In this paper the cosmic ray tests performed at sea level on a few ARGO RPC prototypes are described.

A cheap and practical alternative to plastic scintillating tracker for large surface detectors is developed. Large scale prototype was built and tested, showing high perfomance, good reliability and outstanding ease of production and handling. The worked out technology ensure low cost and high uniformity production of tracker modules, based on commercially available components.

Materials used in the realization of supports for massive cryogenic detectors must have several properties which should be known down to the detector working temperature. This does not always happens, because of the difficulties in the measurement of material characteristics at very low temperatures. We studied the thermal properties of a Polypropylene copolymer (PP) at temperatures as close as possible to the working temperature (10 mK) of CUORE (Cryogenic Underground Observatory for Rare Events), in view of the possible use of PP in the realization of the supports for the TeO₂ crystal absorbers (750g). From the data obtained we conclude that, from a thermal point of view, PP is adequate for use as support material in cryogenic massive detectors.

Ti based TES (Transition Edge Sensor) both of the single layer type and bilayers have been produced with critical temperatures ranging between 140 and 390 mK. Gain up to 400 have been obtained. A possible application of TES as temperature reference point is examined.

We have measured the electron-phonon decoupling in Neutron Trasmutation Doped (NTD) Germanium thermistors down to 20 mK. We find that, in our sample (NTD 31), the thermal decoupling can be well described by the hot-electron model. Thanks to the particular experimental configuration, both electron-phonon decoupling parameters and contact parameters (Kapitza resistence) are obtained from the fit of data. Our results are consistent with those obtained for other doping concentrations of NTD Ge^1,2,3. Thermistors made of NTD 31 Ge will be used as sensors in the CUORICINO⁴ experiment, a forerunner and test of the larger CUORE (Cryogenic Underground Obsevatory for Rare Events) experiment. The knowledge of the electron-phonon decoupling parameters, together with the measure of pulse rise-time detected in a bolometer, allows the electronic thermal heat capacity of the sensor to be evaluated.

A MICROMEGAS detector was combined with a single GEM to allow preamplification before primary electrons enter the main detector. The preamplification not only extends the maximum achievable gas gain without discharge but also it minimizes spark rates when exposed to high intensity ionizing particles. We performed both laboratory and beam tests with various gas mixtures to find optimal operational characteristics and the results were encouraging and this particular combination may be suitable for experiments that require high counting rates and good spatial resolution as in VLHC.

Gravitational waves propagating from rapidly accelerating star masses can be detected by means of interferometric techniques. Several interferometric antennas are presently under construction around the world with the aim of gravitational waves detection in the frequency range starting from a few tens of Hz to a few kHz. In the low frequency region (below a few tens of Hz) their detection is limited by seismic noise which can mask the weak signal induced by a gravitational wave impinging on a suspended mirror. In order to overcome this limitation, the VIRGO collaboration has developed and built a sophisticated suspension system to isolate the optical components from the seismic noise. This mechanical system, called SuperAttenuator, is able to inhibit the transmission of any mechanical disturbances starting from about 4 Hz thus extending the detection band in the low frequency region.

In this paper the design of a CMOS transconductance amplifier, able to drive couples of quantum well diodes, is discussed. The circuit is proposed in two different implementations whose selection depends on the availability of a single well or a twin well technology. Both the implementations are characterized by an intrinsic control of input stages' threshold and gain-linearity (THD < 1% for twin well technologies), as well as by a 3 dB bandwidth >100 MHz.

The advanced study of new photo detector - Silicon Photomultiplier (SiPM) is presented. SiPM consists of many (~10³ mm^-2) silicon micro pixels, which are independent photon micro counters working in limited Geiger mode with a gain of 10⁶. The SiPM output signal is a sum of the signals from a number of pixels fired by photons. The main features of SiPM are: low excess noise factor, the photon detection efficiency at the level of vacuum PMT, low bias voltage (~24V). The timing of the SiPM is about 30 ps for 10 photoelectrons. The possibilities of SiPM applications based on experimental tests are demonstrated: sci fiber readout, scintillator-shifter system readout, possible application for hadron calorimeters.

No abstract received.

With its over 80,000 scintillating lead tungstate PbWO₄ (PWO) crystals the CMS electromagnetic calorimeter (ECAL) will be the largest one ever constructed. It was designed to work in the demanding LHC environment and give a resolution of 0.5% for photon energies above 50 GeV/c. An important R & D effort was necessary in order to guarantee the production of PWO crystals able to satisfy such challenging constraints. The performance of the pre-production crystal batches (about 6000 barrel crystals) is consistent with the very strict quality parameters defined by the ECAL Collaboration. The meaning of quality controls as well as the main characteristics of these crystals are discussed. More, recent developments in the PWO crystal growth technology may speedup the crystal supplying for the ECAL construction.

Crystal matrices are often used in applications where high spatial resolution in the determination of the photon interaction point is necessary. Recent studies have demonstrated the possibility to readout matrices with a large number of crystals by means of WLS fibres coupled to multi-pixel HPD. Latest advances in this method are presented together with a Monte Carlo study for a new shape of finger crystals that could increase the light collection.

The sensitivity for WIMP detection can be improved by an ability to efficiently discriminate the γ and β backgrounds from the nuclear recoil signals. The CRESST phase II detectors will achieve this discrimination by means of simultaneous measurement of phonons and scintillation light. We report on the development of a 300 g detector module consisting of two separate calorimeters fitted with tungsten phase transition thermometers. A 300 g CaWO₄ crystal serves as the target material in which a recoiling WIMP creates both phonons and scintillation light. Phonons are detected by a thermometer on the CaWO₄ crystal. A second smaller detector in close proximity detects the scintillation light. Measurements with this setup will be presented.

In a comparative study the performance of sub-arrays consisting of large CeF₃ and PbWO₄ crystals has been investigated with high energy photons below 1GeV. Energy and time resolutions are determined and compared to the corresponding values for BaF₂ based on the experience of operating the electromagnetic calorimeter TAPS. Since clean photon detection relies on the discrimination and identification of charged and neutral particles, the response to hadrons including time-of-flight and pulse-shape techniques are discussed in detail.

The pure Cherenkov radiator Lead Fluoride (PbF₂) is for the first time used as a material for a medium scale (1022 crystals) fast (20ns dead time) homogeneous absorbing electromagnetic calorimeter with good energy resolution . It allows event recording rate of close to 100 MHz in the solid angle of the calorimeter corresponding to single channel event processing rates of 100-200 kHz depending on scattering angle. The first experiences after 1500 hours of successfull beam time are summarized and the performance concerning calibration and energy resolution for the first 511 channels is presented here.

No abstract received.

Radiation effects in silicon detectors to be used in future high energy physics experiments are discussed. A short overview is given of the major changes in the operational parameters due to radiation damage, and their origin in the radiation-induced microscopic disorder in the silicon bulk. The relevant radiation hardening technologies are described, that have been adopted by the high energy physics community to face the hostile radiation environment where silicon pixel and microstrip detectors will operate in the Large Hadron Collider.

Integrated microscopic investigations of bipolar junction damages in silicon detectors following neutron irradiation and studies of the degradation of the performance of bipolar transistors, due to generation of defects in silicon irradiated with neutron and ion carbons, were performed. The integrated microscopic investigations were studied by means of an advanced contact potential difference (CPD) method in atomic force microscopy (AFM). It was shown that gain degradation appears and that the density of generated defects is the same for neutron and carbon irradiation, but the density of created Frenkel pairs (interstitial-vacancy) is smaller for neutrons than for carbon ions. The value of Δ(1/β) of the transistor was evaluated from the density of Frenkel pairs (CF), for given value of Φ. The dependence of Δ(1/β) on concentration of CF for lateral and vertical pnp juntions at I_c=1μm, was shown. Fron the data of density of Frenkel pairs as a function of ratio Φ (R), was obtained, R=CF/Φ. Ratio R was independent on Φ, for a given type of irradiation (neutrons or carbon ions). For carbon ions, R depends on the value of the energy of incident particles (medium energy 11.1 MeV/a and high energy 95.0 MeV/a of the carbon ions.

The effects of ionizing radiation on P and N-channel devices belonging to a CMOS process with a minimum channel feature of 0.18 μm have been investigated. The aim is to assess the radiation hardness of recent submicron CMOS technologies in view of applications to high granularity detectors and imaging systems. Static, signal and noise parameters were monitored throughout irradiation steps up to a 100 kGy absorbed dose of ⁶⁰Co γ-rays, and compared to the results of the radiation hardness characterization of a 0.35 μm BiCMOS process.

The possibility of the usage of commercial off-the-shelf (COTS) components in Low Earth Orbit (LEO) space payloads is examined in this paper. Several discrete, analog and digital components have been tested for total dose, including diodes BJTs, MOSFETs, etc. The results of these tests are reported and discussed. The radiation source used for this test was the CALLIOPE Cobalt-60 gamma-ray source at ENEA Casaccia (Rome). The maximum radiation dose was 30 krad and the test has been performed according the ESA/SSC 22900 specifications.

A cold irradiation test facility operated at the IBR-2 reactor of JINR, Dubna, is used to investigate the behaviour under neutron and γ irradiations of samples of materials and equipments to be used in the ATLAS forward (FCAL) and the hadronic end cap (HEC) liquid argon calorimeters. The samples under study are immersed in a liquid argon cryostat and exposed to fast neutron (E_n ≥ 100 keV) fluences of about 10¹⁶ n cm^-2 equivalent to the neutron fluence accumulated in FCAL during ten years of LHC operation. An α-cell is used to check for possible outgassing due to irradiation of the samples immersed in liquid argon and to monitor the liquid argon purity. The results of various irradiation tests performed at this facility are reported.

During the 2000/2001 HERA shutdown a silicon strip vertex detector (MVD) was installed in the ZEUS experiment. The frontend chip, Helix128-3.0, fabricated in the radiation tolerant 0.8 μm CMOS technology by AMS, will be exposed to an estimated dose of 20 krad/year. The chips have been irradiated up to an integrated dose of 500 krad using a ⁶⁰Co source. In a testbeam the effect of the radiation on the S/N and on the position resolution have been investigated. The tests show that the S/N-ratio drops from 22 to 12 after 500 krad. When the operation point of the chip is changed a S/N-ratio of 18 corresponding to a position resolution of 9.7 μm can still be achieved even after 500 krad.

Radiation induced optical absorption processes were studied at room temperature for a set of NaPO₃-GdPO₄ phosphate glasses doped by Tb³⁺ ions. Closely similar features were found under X-ray and γ-ray irradiations, while under the intense 308 nm XeCl excimer laser irradiation these effects were further obscured by a possible surface damage. The induced absorption band at 3.3–3.4 eV was ascribed to Tb⁴⁺, while bands at 2.3 eV, 2.9 eV and above 4 eV are related to the host matrix-based color centers.

Pure and doped lithium fluoride (LiF) crystals are well-known dosimeter materials. In this work we report the preliminary results about a careful optical characterisation of polycrystalline LiF films thermally evaporated on fused silica substrates and gamma-irradiated at several doses up to 10⁶ Gy in air. Gamma irradiation of LiF films gives rise to stable formation of primary and aggregate defects. Among them, F centres give rise to the absorption band peaked at 245 nm, while F₂ and F₃⁺ centres are responsible for the absorption in the blue region and for stable and intense green (F₃⁺) and red (F₂) photoluminescence at room temperature. Photoluminescence spectra were measured with both a commercial and a laboratory apparatus. A simplified set-up for optically stimulated luminescence reading was tested. The results are encouraging to propose LiF film on fused silica substrate as dosimeter for gamma irradiation.

The radiation induced degradation of the optical transmission of the fibers SCSF-38M, SCSF-81M (Kuraray), BCF-60 and BCF-98 (Bicron) with polystyrene core (PS) was studied. During and after irradiation with a 100 kV X-ray source, a ¹³⁷Cs source and a ⁶⁰Co source the effects depend on the fiber type: (1) The permanent damage for BCF-98 (clear PS) is smaller than for the scintillators. (2) The BCF-60 is radiation harder than the other two scintillators but very light sensitive.

Temperature treatments (up to 68°C) of SCSF-38M, without irradiation showed a transmission loss which clearly rises with the increasing temperature. This accelerated ageing phenomenon does not recover and the fiber is permanently damaged. In an additional experiment it was studied whether the transmission damage can be influenced by short illuminations with visible light during and after irradiation. For SCSF-38M a strong reduction of the permanent induced absorption remaining after the end of the recovery process was observed.

We have studied the electron beam effects on Poly (Vinyl Chloride) powders without additives, when the irradiation was conducted in inert atmosphere. Then the powders were stored at room temperature for several months.

Our study has evidenced that the PVC interaction with electron beam is not a selective process, because the radiation has sufficient energy to break off all the polymer bonds. So the irradiation process produces a large number of radicals, which unexpectedly carries on the chain reaction also after several months of storage.

The technology of complex metallurgical doping was developed to improve the radiation hardness of magnetic microsensors (MMS) based on III-V semiconductor microcrystals grown through chemical transport reaction methods. To form drains for radiation-enhanced defects in the semiconductor volume and to localize them, it is proposed to dope InSb and InAs microcrystals with the main donor impurity (Sn), additional doping impurities (Mn, Cr) and special supplements (Au, Al, Yb). The influence of irradiation on the electrophysical properties of III-V microcrystals and parameters of MMS manufactured according to the proposed technology has been investigated for fast neutron fluences from 10¹⁴n·cm^-2 up to 10¹⁶n·cm^-2. It was found out that the relative change of carrier concentration in InSb〈Sn:Cr〉 microcrystals under a neutron irradiation fluence of 10¹⁵n·cm^-2 does not exceed 0.03%, the accuracy level of the measurement bench.

LIST OF PARTICIPANTS.