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Nuclear Science, IEEE Transactions on

Issue 3  Part 1 • Date Jun 2001

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Displaying Results 1 - 25 of 71
  • Development of a fully integrated readout system for high count rate position-sensitive measurements of X-rays using silicon strip detectors

    Publication Year: 2001 , Page(s): 466 - 472
    Cited by:  Papers (8)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (132 KB) |  | HTML iconHTML  

    The paper describes the development of a multichannel readout system for X-ray measurements using silicon strip detectors. The system comprises two application-specific integrated circuits (ASICs), a front-end chip, and a digital data storage chip. In the front-end ASIC, a binary readout scheme is employed. The binary data are stored in the asynchronous counters and read out serially at the end of the measurement sequence. The front-end circuit is designed such that it can work with direct current coupled detectors with a leakage current up to few nanoamperes. The size of the input device is optimized for a detector capacitance in the range from 2-5 pF per strip. An equivalent noise charge of 110 electrons rms has been achieved for the total strip capacitance of 2.5 pF at the peaking time of 1 μs. Low noise performance and high counting-rate capability have been demonstrated by measurements of X-ray spectra. View full abstract»

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  • Adaptive digital filter for high-rate high-resolution gamma spectrometry

    Publication Year: 2001 , Page(s): 461 - 465
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (88 KB) |  | HTML iconHTML  

    By automatically adapting the noise filtering time to individual pulse intervals, the preloaded digital filter (PLDF) combines low- to medium-rate resolutions comparable to those of high-quality Gaussian amplifiers with throughput rates of up to 100 kc/s and high-rate resolutions superior to those of state-of-the-art gated integrator systems. In contrast to commercially available digital filters, the PLDF in its new implementation performs pulse shortening as well as pole-zero cancellation in the analog domain. This not only results in a simpler digital core, but also, for the first time, makes possible the use of a low-cost analog-digital converter in a spectrometric application. Combined with real-time correction of counting losses according to the loss-free counting method, the PLDF is the core of a novel multichannel analyzer system for neutron activation analysis of short-lived isomeric transition. View full abstract»

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  • The tile hadronic calorimeter for the ATLAS experiment

    Publication Year: 2001 , Page(s): 367 - 371
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (157 KB) |  | HTML iconHTML  

    Tilecal is the barrel hadron calorimeter of ATLAS. An extensive research and development program was carried out, and three full-size prototype modules were produced and tested from 1996 to 1998. Following ATLAS internal reviews, the construction of the calorimeter started in 1998; about 30% of the modules of the calorimeter are already constructed. We report on the experience of the mass production of the optical components and modules of the tile calorimeter. View full abstract»

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  • Design and performance of the level 1 calorimeter trigger for the BABAR detector

    Publication Year: 2001 , Page(s): 541 - 546
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (322 KB)  

    Since May 1999 the BABAR detector has been taking data at the PEP-II asymmetric electron-positron collider at the Stanford Linear Accelerator Center, CA. This experiment requires a very large data sample and the PEP-II accelerator uses intense beams to deliver the high collision rates needed. This poses a severe challenge to the BABAR trigger system, which must reject the large rate of background signals resulting from the high beam currents whilst accepting the collisions of interest with very high efficiency. One of the systems that performs this task is the Level 1 Calorimeter Trigger, which identifies energy deposits left by particles in the BABAR calorimeter. It is a digital, custom, fixed latency system which makes heavy use of high-speed FPGA devices to allow flexibility in the choice of data filtering algorithms. Results from several intermediate processing stages are read out, allowing the selection algorithm to be fully analyzed and optimized offline. In addition, the trigger is monitored in real time by sampling these data and cross-checking each stage of the trigger calculation against a software model. The design, implementation, construction and performance of the Level 1 Calorimeter Trigger during the first year of BABAR operation are presented. View full abstract»

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  • The CLEO-III trigger: analog and digital calorimetry

    Publication Year: 2001 , Page(s): 547 - 551
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (90 KB) |  | HTML iconHTML  

    The calorimetry subsystem of the CLEO-III Trigger incorporates both analog and digital electronics to provide pipelined trigger information every 42 ns with a latency of approximately 2.5 /spl mu/s. This paper describes the pipelined signal-processing and pattern-recognition schemes used to provide calorimeter information to the experiment trigger with somewhat greater emphasis on the analog components of the system. Analog processing is employed to address the quantization error caused by split energy deposition in adjacent calorimeter cells, and digital field programmable gate arrays are used extensively to filter and categorize the calorimeter energy topology. Timing, geographical, and energy information are all available for use in the calorimeter trigger. View full abstract»

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  • The fast tracker processor for hadron collider triggers

    Publication Year: 2001 , Page(s): 575 - 580
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (94 KB) |  | HTML iconHTML  

    Perspectives for precise and fast track reconstruction in future hadron collider experiments are addressed. We discuss the feasibility of a pipelined highly parallel processor dedicated to the implementation of a very fast tracking algorithm. The algorithm is based on the use of a large bank of pre-stored combinations of trajectory points, called patterns, for extremely complex tracking systems. The CMS experiment at LHC is used as a benchmark. Tracking data from the events selected by the level-1 trigger are sorted and filtered by the Fast Tracker processor at an input rate of 100 kHz. This data organization allows the level-2 trigger logic to reconstruct full resolution tracks with transverse momentum above a few GeV and search for secondary vertices within typical level-2 times. View full abstract»

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  • Conference author index

    Publication Year: 2001 , Page(s): 613 - 615
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    Freely Available from IEEE
  • The implementation of the STAR data-acquisition system using a Myrinet Network

    Publication Year: 2001 , Page(s): 601 - 606
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (76 KB) |  | HTML iconHTML  

    We present results from the first year of operation of the STAR data-acquisition (DAQ) system using a Myrinet Network. STAR is one of four experiments to have been commissioned at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory during 1999 and 2000. The DAQ system is fully integrated with a Level 3 Trigger. The combined system currently consists of 33 Myrinet Nodes, which run in a mixed environment of MVME processors running VxWorksj DEC Alpha workstations running Linux, and SUN Solaris machines. The network will eventually contain up to 150 nodes for the expected final size of the L3 processor farm. Myrinet is a switched high-speed low-latency network produced by Myricom and available for PCI and PMC on a wide variety of platforms. The STAR DAQ system uses the Myrinet Network for messaging, L3 processing, and event building. After the events are built, they are sent via gigabit ethernet to the RHIC computing facility and stored to tape using HPSS. The combined DAQ/L3 system processes 160-MB events at 100 Hz, compresses each event to 20 MB, and performs tracking on the events to implement a physics-based filter to reduce the data storage rate to 20 MB/s View full abstract»

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  • A “cold” discharge mechanism for low-noise fast charge amplifiers

    Publication Year: 2001 , Page(s): 530 - 534
    Cited by:  Papers (15)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (96 KB)  

    We present a new discharge mechanism for low-noise fast preamplifiers for γ-ray spectroscopy. Such circuital solution has been conceived in the framework of the INFN Mars experiment, which imposes stringent requirements for both the signal-to-noise ratio and the rise time of the front-end preamplifiers. Basically, a noninverting low-gain (G) stage is interposed between the output of a conventional charge amplifier and the high-value feedback resistor. It can be easily found that this adds no noise but the discharge time constant is reduced by a factor G, because the voltage drop across the resistor is G times as high, and such is the discharge current. A similar effect could also be obtained in the standard charge amplifier by diminishing the feedback resistor by a factor G. But this would yield an increase of a factor G of its thermal current noise. In this sense our equivalent discharge resistor is “cold”, because it carries a current noise G times as low. This permits us to use a relatively large feedback capacitance which inherently yields a fast risetime. A rise time of 15 ns and an overall electronic noise of 1.03 keV FWNM at 3 μs shaping time have been obtained, with an input capacitance of 33 pF, and 1.5 pF feedback capacitor, 150 μs discharge time constant View full abstract»

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  • A UML-based design process for distributed data-acquisition and triggering systems in high-energy physics experiments

    Publication Year: 2001 , Page(s): 586 - 594
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (92 KB) |  | HTML iconHTML  

    We present the first results in the elaboration of a design and development process that tackles recurrent problems encountered when developing acquisition and triggering systems for high-energy physics experiments., These problems include software/hardware frontier definition and the impact of both intrinsic and performance-related parallelism on software development. Based on the Unified Modeling Language and its extension mechanisms, the process aims at capturing rules, constraints, and simple mechanisms that 1) separate functional concerns from deployment specifications, including hardware-software separation and 2) transparently and automatically derive distribution patterns from system-level definitions. The process is intended to grow progressively into a design framework that will both enforce its rules and constraints and implement design patterns that result from our experience of high-energy physics trigger and data-acquisition system development View full abstract»

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  • Optical characterization under irradiation of Ce3+ (Tb 3+)-doped phosphate scintillating glasses

    Publication Year: 2001 , Page(s): 360 - 366
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    Radiation hardness is one of the fundamental parameters characterizing a scintillator. The reason is that ionizing radiation often induces the formation of color centers in the irradiated material. These centers are related to lattice defects and may absorb light in the visible range. Possible overlap of the induced absorption spectrum with the emission spectrum of the scintillator can reduce the number of photons emitted by the scintillator, influencing negatively the energy resolution of the detector. In this paper, the irradiation (60Co) induced absorption of Ce3+ (Tb3+) phosphate scintillating glasses is reported in the dose range 1-10 Gy. Irradiation tests were performed in the “Calliope” irradiation plant, placed in the Research Centre ENEA-Casaccia in the same dosimetric point (3.7 Gy/h), and the irradiation-induced damage was investigated by transmission measurements. Results are discussed by taking into account the possible dependence of radiation hardness on the composition of glass matrix View full abstract»

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  • Testing and modeling Ethernet switches and networks for use in ATLAS high-level triggers

    Publication Year: 2001 , Page(s): 607 - 612
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (136 KB) |  | HTML iconHTML  

    The ATLAS second-level trigger will use a multilayered local-area network to transfer 5-Gbyte/s detector data from ~1500 buffers to a few hundred processors. A model of the network has been constructed to evaluate its performance. A key component of the network model is a model of an individual switch, reproducing the behavior measured in real devices. A small number of measurable parameters are used to model a variety of commercial Ethernet switches. Using parameters measured on real devices. The impact on the overall network performance is modeled. In the ATLAS context, both 100-Mbit and gigabit Ethernet links are required. A system is described that is capable of characterizing the behavior of commercial switches with the required number of nodes under traffic conditions resembling those to be encountered in the ATLAS experiment. Fast Ethernet traffic is provided by a high-density custom-built tester based on field-programmable gate arrays, programmed in Handel-C and VHDL, while the gigabit Ethernet traffic is generated using Alteon NICs with custom firmware. The system is currently being deployed with 32 100-Mbit ports and 16 gigabit ports, and will be expanded to ~256 nodes of 100 Mbit and ~50 GBE nodes View full abstract»

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  • The fluorescence detector prototype for the Auger project: mechanical structure, optical system, and filter

    Publication Year: 2001 , Page(s): 406 - 410
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (120 KB) |  | HTML iconHTML  

    The Pierre Auger Observatory will study cosmic rays with energy exceeding 1019 eV. The experiment will measure properties of extensive air showers with a hybrid detector consisting of a surface array and an atmospheric fluorescence telescope. This paper presents the characteristics and performance of the optical system for the fluorescence detector prototype. The system adopts a Schmidt camera design with a diaphragm to remove coma aberration. A large spherical mirror (approximately 3.6×3.6 m, with radius of curvature 3.47 m), segmented in 49 trapezoidal elements, is supported by a mechanical structure, where segments are positioned on the meridians of the spherical cap. At the diaphragm, an absorption filter is installed to preferentially transmit the nitrogen fluorescence light. The construction technique, image characteristics, and results of tests performed on the system are discussed View full abstract»

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  • A ray-trace-type counter telescope for neutron spectrometry

    Publication Year: 2001 , Page(s): 320 - 324
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (128 KB) |  | HTML iconHTML  

    A compact recoil-proton counter telescope with two position sensitive proportional counters (PSPCs) for neutron spectrometry has been developed. This counter telescope consists of a radiator (a thin polyethylene film), two PSPCs used as ΔE detector, and an Si-SSD used as E detector. Using the position information extracted from two PSPCs, the three-dimensional trajectory of the recoil proton and the recoil angle can be determined event by event. The performance of this counter telescope was tested by measurement of 7.2-MeV neutrons produced from D-D reactions. It was shown that the energy spectra of neutrons could be obtained by determining the energy of each incident neutron using a recoil angle View full abstract»

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  • Driving spectral resolution to the noise limit in semiconductor gamma detector arrays

    Publication Year: 2001 , Page(s): 520 - 523
    Cited by:  Papers (4)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (76 KB) |  | HTML iconHTML  

    Shape-time adjustment of a standard detector circuit improves the resolution of a single pixel of a detector array to the noise limit. The steady flow of gamma generated charge, in a detector bulk, induces fast signal build-up, as the charge arrives near a single pixel. The build-up period is shorter than the electron transition time from contact to contact. The circuit shape-time response is adjusted to overlap with the fast build-up period. The shape time determines a distance range, extending from the negative contact, where the detector signal does not depend on the position of photon absorption. The noise limited line width is consistent with published data of higher line resolution than predicted by the small pixel theory View full abstract»

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  • Monitoring light source for CMS lead tungstate crystal calorimeter at LHC

    Publication Year: 2001 , Page(s): 372 - 378
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (184 KB) |  | HTML iconHTML  

    Light monitoring will serve as an intercalibration for Compact Muon Solenoid (CMS) lead tungstate crystals in situ at the Large Hadronic Collider, which is crucial for maintaining crystal calorimeter's subpercent constant term in the energy resolution. This paper presents the design of the CMS electromagnetic calorimeter monitoring light source and high-level distribution system. The correlations between variations of the light output and the transmittance for the CMS choice of yttrium-doped PbWO4 crystals were investigated and were used to study monitoring linearity and sensitivity as a function of wavelength. The monitoring wavelength was determined so that a good linearity as well as adequate sensitivity can be achieved. The performance of a custom manufactured tunable laser system is presented. Issues related to monitoring precision are discussed View full abstract»

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  • Multi-anode sawtooth SDD for X-ray spectroscopy fabricated on NTD wafers

    Publication Year: 2001 , Page(s): 258 - 261
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (76 KB) |  | HTML iconHTML  

    We are developing a multi-anode sawtooth silicon drift detector (MSSDD) with an anode pitch of 250 μm for one-dimensional position-sensitive detection of low-energy X-rays down to ~200 eV. The detector is intended to be used in X-ray diffraction analysis. In this paper, we present new results of X-ray spectroscopy measurements with detectors fabricated on neutron transmutation doped (NTD) wafers with a thickness of 290 μm. Using an MSSDD with an anode pitch of 250 μm and having p+ strips on both sides, we have measured an energy resolution of 191-eV full-width half-maximum (FWHM) per anode pixel for the 5.89 keV line of 55Fe at 213 K. At room temperature the energy resolution is 375 eV FWHM. Split events are almost completely eliminated due to the sawtooth-shaped p+ strips View full abstract»

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  • A high-voltage power supply operating under a magnetic field

    Publication Year: 2001 , Page(s): 535 - 540
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (108 KB) |  | HTML iconHTML  

    This paper describes the performance of a high-voltage power supply incorporating a ceramic transformer. Since the transformer is constructed using a ceramic bar containing no magnetic material, the power supply can operate under a magnetic field of 1.5 Tesla with no degradation of performance. Feedback is used to stabilize high-voltage output such that a supply voltage of 3 V provides from 1500 to 2500 V at a load of more than 10 MΩ with efficiency higher than 50%; and with a supply voltage of 2 V, 3000 V is supplied at a load of 20 MΩ. In fact, a supply voltage of 5 V is sufficient to provide 4000 V at the same load. A network of high-voltage power supplies is also described. Most functions of the power supply are thereby monitored and controlled through the network View full abstract»

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  • PreFPIX2: core architecture and results

    Publication Year: 2001 , Page(s): 485 - 492
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (100 KB) |  | HTML iconHTML  

    PFIX is a pixel architecture designed for colliding-beam experiments at the Tevatron. Its most important application to date is the BTeV experiment. PreFPIX2 is a chip designed to test the FPIX Core, i.e., the pixel control and readout architecture. This FPIX Core will be mated to a periphery specific to a particular experiment. Earlier plans called for the BTeV FPIX chip to be designed in a rad-hard process. However, deep-submicron CMOS processes have demonstrated appropriate radiation tolerance at a lower cost and with greater reliability. Therefore, PreFPIX2 has been fabricated in a 0.25 micrometer process utilizing radiation tolerant design techniques. The architecture has undergone substantial development from earlier versions of FPIX. Most notable are the improvements to the column token passing scheme and to the end-of-column logic. Extensive simulations were performed using both SPICE and structural-level Verilog. Monte Carlo physics simulations of the BTeV pixel detector at half, full and double the planned luminosity were converted to Verilog compatible input files for the chip simulations, allowing the designers to observe the chip operating under real conditions and for extended periods of time. Analyzes of the results reveal that at all luminosities the FPIX Core correctly identifies better than 99.6% of input hits. Bench tests of fabricated chips confirm the accuracy of the simulations View full abstract»

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  • A xenon gas proportional scintillation counter with a UV-sensitive large-area avalanche photodiode

    Publication Year: 2001 , Page(s): 312 - 319
    Cited by:  Papers (14)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (152 KB) |  | HTML iconHTML  

    The performance characteristics of a xenon gas proportional scintillation counter comprising a large-area avalanche photodiode with enhanced ultraviolet sensitivity were evaluated. By integrating the photodiode within the xenon gas envelope of the scintillator, the intervening quartz window was eliminated. Energy resolutions of 7.8% and 4.4% were measured for 5.9- and 22.1-keV X-rays, respectively. The results demonstrate that large-area avalanche photodiodes may replace photomultiplier tubes without compromising the performance of the gas proportional scintillation counter View full abstract»

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  • PETRIC-a positron emission tomography readout integrated circuit

    Publication Year: 2001 , Page(s): 479 - 484
    Cited by:  Papers (20)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (140 KB) |  | HTML iconHTML  

    We present the architecture, critical design issues, and performance measurements of PETRIC, a 64-channel mixed signal front-end integrated circuit for reading out a photodiode array coupled with Lu 2SiO5[Ce] scintillator crystals for a medical imaging application: positron emission topography. Each channel consists of a low-noise charge-sensitive preamplifier, an RC-CR pulse shaper and a winner-take-all multiplexer that selects the channel with the largest input signal. Triggered by an external timing signal, a switch opens and a capacitor stores the peak voltage of the winner channel. The shaper peaking time is adjustable by means of external current inputs over a continuous range of 0.7 μs to 9 μs. Power consumption is 5.4 mW per channel, measured equivalent noise charge at 1-μs peaking time, zero leakage current is 33 rms electrons plus 7.3 rms electrons per pF of input capacitance. Design is fabricated in 0.5-μm 3.3-V complementary metal-oxide semiconductor technology View full abstract»

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  • Simultaneous ballistic deficit immunity and resilience to parallel noise sources: A new pulse shaping technique

    Publication Year: 2001 , Page(s): 450 - 454
    Cited by:  Papers (5)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (96 KB) |  | HTML iconHTML  

    A new and different time-variant pulse processing system has been developed based on a simple CR-RC filter and two analog switches. The new pulse processing technique combines both ballistic deficit immunity and resilience to parallel noise without a significant compromise to the low energy resolution, generally considered a mutually exclusive requirement. The filter is realized by combining two different pulse shaping techniques. One of the techniques creates a low rate of curvature at the pulse peak, which reduces ballistic deficit, while the second technique increases the tolerance to low-frequency noise by modifying the noise history. Several experimental measurements are presented, including tests on a coplanar grid CdZnTe detector. Improvements on both the resolution and line shape are shown for the 662 keV line of 137Cs View full abstract»

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  • A new detection system with polycapillary conic collimator for high-localized analysis of X-ray fluorescence emission

    Publication Year: 2001 , Page(s): 268 - 271
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (100 KB) |  | HTML iconHTML  

    In this paper, we present a new detection system conceived for the X-ray fluorescence (XRF) analysis of the radiation emitted by very small areas on the sample. The system is based on the use of a polycapillary conic collimator which captures the XRF emitted only from a local area of the sample independently on how extended is the X-ray excitation. The use of a Peltier-cooled silicon drift detector allows to achieve high energy resolution with a very compact system configuration. In this first prototype, a spatial resolution of about 150 μm has been verified in the analysis of thin metal strips. Moreover, the results of a first X-Y scanning for elemental mapping on a sample surface are also reported View full abstract»

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  • The CLEO-III trigger: level 1 decision and gating

    Publication Year: 2001 , Page(s): 562 - 566
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (56 KB) |  | HTML iconHTML  

    The Level 1 decision and data flow control subsystems of the CLEO-III trigger produce and distribute a trigger decision every 42 ns based on input from calorimetry and tracking subsystems. This paper describes the free-running pipelined trigger decision logic that correlates axial and stereo tracking information, and combines time-aligned calorimetry information onto a common backplane. Programmable trigger decision boards monitor this backplane and can be configured as desired to respond to a wide variety of trigger conditions. The resulting trigger decision is regulated by a throttling mechanism that allows the data-acquisition system to modulate the trigger rate to maximize throughput without buffer overrun. A central signal distribution mechanism delivers the trigger decision and system clock to the front-end electronics View full abstract»

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  • High-resolution CdTe detector and applications to imaging devices

    Publication Year: 2001 , Page(s): 287 - 291
    Cited by:  Papers (29)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (292 KB) |  | HTML iconHTML  

    Using a high quality Cadmium Telluride (CdTe) wafer, we formed a Schottky junction and operated the detector as a diode (CdTe diode). The low leakage current of the CdTe diode allows us to apply a much higher bias voltage than was possible with the previous CdTe detectors. For a relatively thin detector of ~0.5 mm thick, the high bias voltage results in a high electric field in the device. Both the improved charge collection efficiency and the low-leakage current lead to an energy resolution of 1.1 keV FWHM at 60 keV for a 2×2 mm2 device and 2 keV for a 10×10 mm2 device at 5°C without any charge-loss correction electronics. For astrophysical applications, we have developed an initial prototype CdTe pixel detector based on the CdTe diode. The detector has 400 pixels with a pixel size of 625×625 μm2. Each pixel is gold-stud bonded to a fanout board and routed to a front end ASIC to measure pulse height information for each γ-ray photon View full abstract»

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