WorldWideScience

Sample records for pixelated czt detectors

  1. Line profile modelling for multi-pixel CZT detectors

    Science.gov (United States)

    Chattopadhyay, T.; Vadawale, S. V.; Rao, A. R.; Bhattacharya, D.; Mithun, N. P. S.; Bhalerao, V.

    2016-07-01

    Cadmium Zinc Telluride (CZT) detectors have been the mainstay for hard X-ray astronomy for its high quantum efficiency, fine energy resolution, near room temperature operation, and radiation hardness. In order to fully utilize the spectroscopic capabilities of CZT detectors, it is important to generate accurate response matrix, which in turn requires precise modelling of the line profiles for the CZT detectors. We have developed a numerical model taking into account the mobility and lifetime of the charge carriers and intrpixel charge sharing for the CZT detectors. This paper describes the details of the modelling along with the experimental measurements of mobility, lifetime and charge sharing fractions for the CZT detector modules of thickness of 5 mm and 2.5 mm pixel size procured from Orbotech Medical Solutions (same modules used in AstroSat-CZTI).

  2. Test of CZT Detectors with Different Pixel Pitches and Thicknesses

    CERN Document Server

    Li, Qiang; Jung, Ira; Groza, Michael; Dowkontt, Paul; Bose, Richard; Simburger, Garry; Burger, Arnold; Krawczynski, Henric

    2007-01-01

    The Modified Horizontal Bridgman (MHB) process produces Cadmium Zinc Telluride (CZT) crystals with high yield and excellent homogeneity. Various groups,including our own, previously reported on the test of 2x2x0.5 cm3 MHB CZT detectors grown by the company Orbotech and read out with 8x8 pixels. In this contribution, we describe the optimization of the photolithographic process used for contacting the CZT detector with pixel contacts. The optimized process gives a high yield of good pixels down to pixel diameters/pitches of 50 microns. Furthermore, we discuss the performance of 0.5 cm and 0.75 cm thick detectors contacted with 64 and 225 pixel read out with the RENA-3 ASICs from the company NOVA R&D.

  3. Fabrication and Test of Pixelated CZT Detectors with Different Pixel Pitches and Thicknesses

    CERN Document Server

    Li, Q; Dowkontt, P; Martín, J; Beilicke, M; Jung, I; Groza, M; Bürger, A; De Geronimo, G; Krawczynski, H

    2008-01-01

    The main methods grown Cadmium Zinc Telluride (CZT) crystals with high yield and excellent homogeneity are Modified Horizontal Bridgman (MHB) and High Pressure Bridgman (HPB) processes, respectively. In this contribution, the readout system based on two 32-channel NCI-ASICs for pixellated CZT detector arrays has been developed and tested. The CZT detectors supplied by Orbotech (MHB) and eV products (HPB) are tested by NCI-ASIC readout system. The CZT detectors have an array of 8x8 or 11x11 pixel anodes fabricated on the anode surface with the area up to 2 cm x2 cm and the thickness of CZT detectors ranges from 0.5 cm to 1 cm. Energy spectra resolution and electron mobility-lifetime products of 8x8 pixels CZT detector with different thicknesses have been investigated.

  4. Anode readout for pixellated CZT detectors

    Science.gov (United States)

    Narita, Tomohiko; Grindlay, Jonathan E.; Hong, Jaesub; Niestemski, Francis C.

    2004-02-01

    Determination of the photon interaction depth offers numerous advantages for an astronomical hard X-ray telescope. The interaction depth is typically derived from two signals: anode and cathode, or collecting and non-collecting electrodes. We present some preliminary results from our depth sensing detectors using only the anode pixel signals. By examining several anode pixel signals simultaneously, we find that we can estimate the interaction depth, and get sub-pixel 2-D position resolution. We discuss our findings and the requirements for future ASIC development.

  5. Small pixel CZT detector for hard X-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Matthew David, E-mail: Matt.Wilson@stfc.ac.uk [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxfordshire OX11 0QX (United Kingdom); Cernik, Robert [Henry Moseley X-ray Imaging Facility, School of Materials, University of Manchester (United Kingdom); Chen, Henry [Redlen Technologies, Saanichton, British Columbia (Canada); Hansson, Conny [Henry Moseley X-ray Imaging Facility, School of Materials, University of Manchester (United Kingdom); Iniewski, Kris [Redlen Technologies, Saanichton, British Columbia (Canada); Jones, Lawrence L.; Seller, Paul; Veale, Matthew C. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxfordshire OX11 0QX (United Kingdom)

    2011-10-01

    A new small pixel cadmium zinc telluride (CZT) detector has been developed for hard X-ray spectroscopy. The X-ray performance of four detectors is presented and the detectors are analysed in terms of the energy resolution of each pixel. The detectors were made from CZT crystals grown by the travelling heater method (THM) bonded to a 20x20 application specific integrated circuit (ASIC) and data acquisition (DAQ) system. The detectors had an array of 20x20 pixels on a 250 {mu}m pitch, with each pixel gold-stud bonded to an energy resolving circuit in the ASIC. The DAQ system digitised the ASIC output with 14 bit resolution, performing offset corrections and data storage to disc in real time at up to 40,000 frames per second. The detector geometry and ASIC design was optimised for X-ray spectroscopy up to 150 keV and made use of the small pixel effect to preferentially measure the electron signal. A {sup 241}Am source was used to measure the spectroscopic performance and uniformity of the detectors. The average energy resolution (FWHM at 59.54 keV) of each pixel ranged from 1.09{+-}0.46 to 1.50{+-}0.57 keV across the four detectors. The detectors showed good spectral performance and uniform response over almost all pixels in the 20x20 array. A large area 80x80 pixel detector will be built that will utilise the scalable design of the ASIC and the large areas of monolithic spectroscopic grade THM grown CZT that are now available. The large area detector will have the same performance as that demonstrated here.

  6. Small pixel CZT detector for hard X-ray spectroscopy

    Science.gov (United States)

    Wilson, Matthew David; Cernik, Robert; Chen, Henry; Hansson, Conny; Iniewski, Kris; Jones, Lawrence L.; Seller, Paul; Veale, Matthew C.

    2011-10-01

    A new small pixel cadmium zinc telluride (CZT) detector has been developed for hard X-ray spectroscopy. The X-ray performance of four detectors is presented and the detectors are analysed in terms of the energy resolution of each pixel. The detectors were made from CZT crystals grown by the travelling heater method (THM) bonded to a 20×20 application specific integrated circuit (ASIC) and data acquisition (DAQ) system. The detectors had an array of 20×20 pixels on a 250 μm pitch, with each pixel gold-stud bonded to an energy resolving circuit in the ASIC. The DAQ system digitised the ASIC output with 14 bit resolution, performing offset corrections and data storage to disc in real time at up to 40,000 frames per second. The detector geometry and ASIC design was optimised for X-ray spectroscopy up to 150 keV and made use of the small pixel effect to preferentially measure the electron signal. A 241Am source was used to measure the spectroscopic performance and uniformity of the detectors. The average energy resolution (FWHM at 59.54 keV) of each pixel ranged from 1.09±0.46 to 1.50±0.57 keV across the four detectors. The detectors showed good spectral performance and uniform response over almost all pixels in the 20×20 array. A large area 80×80 pixel detector will be built that will utilise the scalable design of the ASIC and the large areas of monolithic spectroscopic grade THM grown CZT that are now available. The large area detector will have the same performance as that demonstrated here.

  7. Fabrication and Test of Pixelated CZT Detectors with Different Pixel Pitches and Thicknesses

    OpenAIRE

    Li, Q.; Garson, A.; Dowkontt, P.; Martin, J.; Beilicke, M; Jung, I.; Groza, M.; A. Burger; De Geronimo, G.; Krawczynski, H.; .

    2008-01-01

    The main methods grown Cadmium Zinc Telluride (CZT) crystals with high yield and excellent homogeneity are Modified Horizontal Bridgman (MHB) and High Pressure Bridgman (HPB) processes, respectively. In this contribution, the readout system based on two 32-channel NCI-ASICs for pixellated CZT detector arrays has been developed and tested. The CZT detectors supplied by Orbotech (MHB) and eV products (HPB) are tested by NCI-ASIC readout system. The CZT detectors have an array of 8x8 or 11x11 pi...

  8. HEXITEC ASIC-a pixellated readout chip for CZT detectors

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Lawrence [STFC Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom)], E-mail: l.l.jones@stfc.ac.uk; Seller, Paul; Wilson, Matthew; Hardie, Alec [STFC Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom)

    2009-06-01

    HEXITEC is a collaborative project with the aim of developing a new range of detectors for high-energy X-ray imaging. High-energy X-ray imaging has major advantages over current lower energy imaging for the life and physical sciences, including improved phase-contrast images on larger, higher density samples and with lower accumulated doses. However, at these energies conventional silicon-based devices cannot be used, hence, the requirement for a new range of high Z-detector materials. Underpinning the HEXITEC programme are the development of a pixellated Cadmium Zinc Telluride (CZT) detectors and a pixellated readout ASIC which will be bump-bonded to the detector. The HEXITEC ASIC is required to have low noise (20 electrons rms) and tolerate detector leakage currents. A prototype 20x20 pixel ASIC has been developed and manufactured on a standard 0.35 {mu}m CMOS process.

  9. HEXITEC ASIC—a pixellated readout chip for CZT detectors

    Science.gov (United States)

    Jones, Lawrence; Seller, Paul; Wilson, Matthew; Hardie, Alec

    2009-06-01

    HEXITEC is a collaborative project with the aim of developing a new range of detectors for high-energy X-ray imaging. High-energy X-ray imaging has major advantages over current lower energy imaging for the life and physical sciences, including improved phase-contrast images on larger, higher density samples and with lower accumulated doses. However, at these energies conventional silicon-based devices cannot be used, hence, the requirement for a new range of high Z-detector materials. Underpinning the HEXITEC programme are the development of a pixellated Cadmium Zinc Telluride (CZT) detectors and a pixellated readout ASIC which will be bump-bonded to the detector. The HEXITEC ASIC is required to have low noise (20 electrons rms) and tolerate detector leakage currents. A prototype 20×20 pixel ASIC has been developed and manufactured on a standard 0.35 μm CMOS process.

  10. Optimization of CZT Detectors with Sub-mm Pixel Pitches Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop and optimize 0.5 cm thick Cadmium Zinc Telluride (CZT) detectors with very small pixel pitches, i.e. 350 micron and 600 micron. The proposed...

  11. Construction and Testing of a Pixellated CZT Detector and Shield for a Hard X-ray Astronomy Balloon Flight

    OpenAIRE

    Bloser, P. F.; Narita, T; Jenkins, J. A.; Grindlay, J.E.

    2000-01-01

    We report on the construction and laboratory testing of pixellated CZT detectors mounted in a flip-chip, tiled fashion and read out by an ASIC, as required for proposed hard X-ray astronomy missions. Two 10 mm x 10 mm x 5 mm detectors were fabricated, one out of standard eV Products high-pressure Bridgman CZT and one out of IMARAD horizontal Bridgman CZT. Each was fashioned with a 4 x 4 array of gold pixels on a 2.5 mm pitch with a surrounding guard ring. The detectors were mounted side by si...

  12. Monte Carlo based performance assessment of different animal PET architectures using pixellated CZT detectors

    Energy Technology Data Exchange (ETDEWEB)

    Visvikis, D. [INSERM U650, LaTIM, University Hospital Medical School, F-29609 Brest (France)]. E-mail: Visvikis.Dimitris@univ-brest.fr; Lefevre, T. [INSERM U650, LaTIM, University Hospital Medical School, F-29609 Brest (France); Lamare, F. [INSERM U650, LaTIM, University Hospital Medical School, F-29609 Brest (France); Kontaxakis, G. [ETSI Telecomunicacion Universidad Politecnica de Madrid, Ciudad Universitaria, s/n 28040, Madrid (Spain); Santos, A. [ETSI Telecomunicacion Universidad Politecnica de Madrid, Ciudad Universitaria, s/n 28040, Madrid (Spain); Darambara, D. [Department of Physics, School of Engineering and Physical Sciences, University of Surrey, Guildford (United Kingdom)

    2006-12-20

    The majority of present position emission tomography (PET) animal systems are based on the coupling of high-density scintillators and light detectors. A disadvantage of these detector configurations is the compromise between image resolution, sensitivity and energy resolution. In addition, current combined imaging devices are based on simply placing back-to-back and in axial alignment different apparatus without any significant level of software or hardware integration. The use of semiconductor CdZnTe (CZT) detectors is a promising alternative to scintillators for gamma-ray imaging systems. At the same time CZT detectors have the potential properties necessary for the construction of a truly integrated imaging device (PET/SPECT/CT). The aims of this study was to assess the performance of different small animal PET scanner architectures based on CZT pixellated detectors and compare their performance with that of state of the art existing PET animal scanners. Different scanner architectures were modelled using GATE (Geant4 Application for Tomographic Emission). Particular scanner design characteristics included an overall cylindrical scanner format of 8 and 24 cm in axial and transaxial field of view, respectively, and a temporal coincidence window of 8 ns. Different individual detector modules were investigated, considering pixel pitch down to 0.625 mm and detector thickness from 1 to 5 mm. Modified NEMA NU2-2001 protocols were used in order to simulate performance based on mouse, rat and monkey imaging conditions. These protocols allowed us to directly compare the performance of the proposed geometries with the latest generation of current small animal systems. Results attained demonstrate the potential for higher NECR with CZT based scanners in comparison to scintillator based animal systems.

  13. Design and Testing of a Prototype Pixellated CZT Detector and Shield for Hard X-Ray Astronomy

    OpenAIRE

    Bloser, P. F.; Grindlay, J.E.; Narita, T; Jenkins, J. A.

    1999-01-01

    We report on the design and laboratory testing of a prototype imaging CZT detector intended for balloon flight testing in April 2000. The detector tests several key techniques needed for the construction of large-area CZT arrays, as required for proposed hard X-ray astronomy missions. Two 10 mm x 10 mm x 5 mm CZT detectors, each with a 4 x 4 array of 1.9 mm pixels on a 2.5 mm pitch, will be mounted in a ``flip-chip'' fashion on a printed circuit board carrier card; the detectors will be place...

  14. Tiled Array of Pixelated CZT Imaging Detectors for ProtoEXIST2 and MIRAX-HXI

    CERN Document Server

    Hong, Jaesub; Grindlay, Jonathan; Rodrigues, Barbara; Ellis, Jon Robert; Baker, Robert; Barthelmy, Scott; Mao, Peter; Miyasaka, Hiromasa; Apple, Jeff

    2013-01-01

    We have assembled a tiled array (220 cm2) of fine pixel (0.6 mm) imaging CZT detectors for a balloon borne wide-field hard X-ray telescope, ProtoEXIST2. ProtoEXIST2 is a prototype experiment for a next generation hard X-ray imager MIRAX-HXI on board Lattes, a spacecraft from the Agencia Espacial Brasilieira. MIRAX will survey the 5 to 200 keV sky of Galactic bulge, adjoining southern Galactic plane and the extragalactic sky with 6' angular resolution. This survey will open a vast discovery space in timing studies of accretion neutron stars and black holes. The ProtoEXIST2 CZT detector plane consists of 64 of 5 mm thick 2 cm x 2 cm CZT crystals tiled with a minimal gap. MIRAX will consist of 4 such detector planes, each of which will be imaged with its own coded-aperture mask. We present the packaging architecture and assembly procedure of the ProtoEXIST2 detector. On 2012, Oct 10, we conducted a successful high altitude balloon experiment of the ProtoEXIST1 and 2 telescopes, which demonstrates their technolog...

  15. CZT detector in multienergy x-ray imaging with different pixel sizes and pitches: Monte Carlo simulation studies

    Science.gov (United States)

    Choi, Yu-Na; Kim, Hee-Joung; Cho, Hyo-Min; Lee, Chang-Lae; Park, Hye-Suk; Kim, Dae-Hong; Lee, Seung-Wan; Ryu, Hyun-Ju

    2011-03-01

    A photon counting detector based on semiconductor materials is a very promising approach for x-ray imaging. Cadmium zinc telluride (CZT) semiconductor has a high atomic number which results in higher absorption coefficients for x-rays. However, the CZT detectors exhibit several problems with hole trapping and charge sharing. Charge sharing occurs due to diffusion of charge and characteristic x-ray escape and scattered x-rays in the detectors. In this study, we evaluated the effect of interaction with CZT detector using Monte Carlo simulations. To demonstrate the effectiveness of CZT detector in clinical application, we reported confirmation of CNR improvement in K-edge images, and material decomposition using energy selective windows. X-ray energy spectrum acquired at 120 kVp tube voltage and 2 mm Al filtration and 10 cm added water phantom in the x-ray beam. Geant4 Application for Tomographic Emission (GATE) version 6.0 was used for a CZT crystal with size of 10x10 mm2 and thickness of 4 mm. The detector pixel with sizes of 0.09x0.09, 0.45x0.45, and 0.90x0.90 mm2 were simulated. For all pixel sizes, the x-ray spectra of the simulations were distorted towards the lower energy region. Because the characteristic x-rays add counts in the range of 20-40 keV. The magnitude of this deterioration is substantial for small pixel sizes. However, we demonstrated that the distortion of spectrum does not greatly affect the x-ray imaging. The GATE simulation model and these results may be used as a basis of development of energy-resolved photon counting x-ray detector. We believe that the CZT detector may enhance the detectability of multi-energy x-ray imaging.

  16. Design and Testing of a Prototype Pixellated CZT Detector and Shield for Hard X-Ray Astronomy

    CERN Document Server

    Bloser, P F; Narita, T; Jenkins, J A

    1999-01-01

    We report on the design and laboratory testing of a prototype imaging CZT detector intended for balloon flight testing in April 2000. The detector tests several key techniques needed for the construction of large-area CZT arrays, as required for proposed hard X-ray astronomy missions. Two 10 mm x 10 mm x 5 mm CZT detectors, each with a 4 x 4 array of 1.9 mm pixels on a 2.5 mm pitch, will be mounted in a ``flip-chip'' fashion on a printed circuit board carrier card; the detectors will be placed 0.3 mm apart in a tiled configuration such that the pixel pitch is preserved across both crystals. One detector is eV Products high-pressure Bridgman CZT, and the other is IMARAD horizontal Bridgman material. Both detectors are read out by a 32-channel VA-TA ASIC controlled by a PC/104 single-board computer. A passive shield/collimator surrounded by plastic scintillator surrounds the detectors on five sides and provides a ~45 deg field of view. The background spectrum recorded by this instrument will be compared to that...

  17. Development of Small-Pixel CZT Detectors for Future High-Resolution Hard X-ray Missions

    Science.gov (United States)

    Beilicke, Matthias

    Owing to recent breakthroughs in grazing incidence mirror technology, next-generation hard X-ray telescopes will achieve angular resolutions of between 5 and 10 arc seconds - about an order of magnitude better than that of the NuSTAR hard X-ray telescope. As a consequence, the next generation of hard X-ray telescopes will require pixelated hard X- ray detectors with pixels on a grid with a lattice constant of between 120 and 240 um. Additional detector requirements include a low energy threshold of less than 5 keV and an energy resolution of less than 1 keV. The science drivers for a high angular-resolution hard X-ray mission include studies and measurements of black hole spins, the cosmic evolution of super-massive black holes, AGN feedback, and the behavior of matter at very high densities. We propose a R&D research program to develop, optimize and study the performance of 100-200 um pixel pitch CdTe and Cadmium Zinc Telluride (CZT) detectors of 1-2 mm thickness. Our program aims at a comparison of the performance achieved with CdTe and CZT detectors, and the optimization of the pixel, steering grid, and guard ring anode patterns. Although these studies will use existing ASICs (Application Specific Integrated Circuits), our program also includes modest funds for the development of an ultra-low noise ASIC with a 2-D grid of readout pads that can be directly bonded to the 100-200 um pixel pitch CdTe and CZT detectors. The team includes the Washington University group (Prof. M. Beilicke and Co-I Prof. H.S.W. Krawczynski et al.), and co-investigator G. De Geronimo at Brookhaven National Laboratory (BNL). The Washington University group has a 10 year track record of innovative CZT detector R&D sponsored by the NASA Astronomy and Physics Research and Analysis (APRA) program. The accomplishments to date include the development of CZT detectors with pixel pitches between 350 um and 2.5 mm for the ProtoExist, EXIST, and X-Calibur hard X-ray missions with some of the best

  18. Hybrid pixel-waveform CdTe/CZT detector for use in an ultrahigh resolution MRI compatible SPECT system

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Liang, E-mail: cai7@illinois.edu [Department of Nuclear, Plasma, and Radiological Engineering, University of Illinois at Urbana Champaign, 216 Talbot Laboratory, 104 S Wrig, Urbana, Urbana, Illinois 61801 (United States); Meng, Ling-Jian [Department of Nuclear, Plasma, and Radiological Engineering, University of Illinois at Urbana Champaign, 216 Talbot Laboratory, 104 S Wrig, Urbana, Urbana, Illinois 61801 (United States)

    2013-02-21

    In this paper, we will present a new small pixel CdTe/CZT detector for sub-500 μm resolution SPECT imaging application inside MR scanner based on a recently developed hybrid pixel-waveform (HPWF) readout circuitry. The HPWF readout system consists of a 2-D multi-pixel circuitry attached to the anode pixels to provide the X–Y positions of interactions, and a high-speed digitizer to read out the pulse-waveform induced on the cathode. The digitized cathode waveform could provide energy deposition information, precise timing and depth-of-interaction information for gamma ray interactions. Several attractive features with this HPWF detector system will be discussed in this paper. To demonstrate the performance, we constructed several prototype HPWF detectors with pixelated CZT and CdTe detectors of 2–5 mm thicknesses, connected to a prototype readout system consisting of energy-resolved photon-counting ASIC for readout anode pixels and an Agilent high-speed digitizer for digitizing the cathode signals. The performances of these detectors based on HPWF are discussed in this paper.

  19. Hybrid pixel-waveform CdTe/CZT detector for use in an ultrahigh resolution MRI compatible SPECT system

    Science.gov (United States)

    Cai, Liang; Meng, Ling-Jian

    2013-02-01

    In this paper, we will present a new small pixel CdTe/CZT detector for sub-500 μm resolution SPECT imaging application inside MR scanner based on a recently developed hybrid pixel-waveform (HPWF) readout circuitry. The HPWF readout system consists of a 2-D multi-pixel circuitry attached to the anode pixels to provide the X-Y positions of interactions, and a high-speed digitizer to read out the pulse-waveform induced on the cathode. The digitized cathode waveform could provide energy deposition information, precise timing and depth-of-interaction information for gamma ray interactions. Several attractive features with this HPWF detector system will be discussed in this paper. To demonstrate the performance, we constructed several prototype HPWF detectors with pixelated CZT and CdTe detectors of 2-5 mm thicknesses, connected to a prototype readout system consisting of energy-resolved photon-counting ASIC for readout anode pixels and an Agilent high-speed digitizer for digitizing the cathode signals. The performances of these detectors based on HPWF are discussed in this paper.

  20. Construction and testing of a pixellated CZT detector and shield for a hard x-ray astronomy balloon flight

    Science.gov (United States)

    Bloser, Peter F.; Narita, Tomohiko; Jenkins, Jonathan A.; Grindlay, Jonathan E.

    2000-12-01

    We report on the construction and laboratory testing of pixellated CZT detectors mounted in a flip-chip, tiled fashion and read out by an ASIC, as required for proposed hard X-ray astronomy missions. Two 10 mm X 10 mm X 5 mm detectors were fabricated, one out of standard eV Products high-pressure Bridgman CZT and one out of IMARAD horizontal Bridgman CZT. Each was fashioned with a 4 X 4 array of gold pixels on 2.5 mm pitch with a surrounding guard ring. The detectors were mounted side by side on a carrier card, such that the pixel pitch was preserved, and read out by a 32-channel VA-TA ASIC from IDE AS Corp. controlled by a PC/104 single-board computer. A passive shield/collimator surrounded by plastic scintillator encloses the detectors on five sides and provides an approximately 40 degree field of view. Thus this experiment tests key techniques required for future hard X-ray survey instruments. The experiment was taken to Ft. Sumner, NM in May 2000 in preparation for a scientific balloon flight aboard the joint Harvard-MSFC EXITE2/HERO payload. Although we did not receive a flight opportunity, and are currently scheduled to fly in September 2000, we present our calibration data in the flight configuration together with data analysis techniques and simulations of the expected flight background spectrum.

  1. Construction and Testing of a Pixellated CZT Detector and Shield for a Hard X-ray Astronomy Balloon Flight

    CERN Document Server

    Bloser, P F; Jenkins, J A; Grindlay, J E

    2000-01-01

    We report on the construction and laboratory testing of pixellated CZT detectors mounted in a flip-chip, tiled fashion and read out by an ASIC, as required for proposed hard X-ray astronomy missions. Two 10 mm x 10 mm x 5 mm detectors were fabricated, one out of standard eV Products high-pressure Bridgman CZT and one out of IMARAD horizontal Bridgman CZT. Each was fashioned with a 4 x 4 array of gold pixels on a 2.5 mm pitch with a surrounding guard ring. The detectors were mounted side by side on a carrier card, such that the pixel pitch was preserved, and read out by a 32-channel VA-TA ASIC from IDE AS Corp. controlled by a PC/104 single-board computer. A passive shield/collimator surrounded by plastic scintillator encloses the detectors on five sides and provides a ~40deg field of view. Thus this experiment tests key techniques required for future hard X-ray survey instruments. The experiment was taken to Ft Sumner, NM in May 2000 in preparation for a scientific balloon flight aboard the joint Harvard-MSFC...

  2. Studying Spatial Resolution of CZT Detectors Using Sub-Pixel Positioning for SPECT

    Science.gov (United States)

    Montémont, Guillaume; Lux, Silvère; Monnet, Olivier; Stanchina, Sylvain; Verger, Loïck

    2014-10-01

    CZT detectors are the basic building block of a variety of new SPECT systems. Their modularity allows adapting system architecture to specific applications such as cardiac, breast, brain or small animal imaging. In semiconductors, a high number of electron-hole pairs is produced by a single interaction. This direct conversion process allows better energy and spatial resolutions than usual scintillation detectors based on NaI(Tl). However, it remains often unclear if SPECT imaging can really benefit of that performance gain. We investigate the system performance of a detection module, which is based on 5 mm thick CZT with a segmented anode having a 2.5 mm pitch by simulation and experimentation. This pitch allows an easy assembly of the crystal on the readout board and limits the space occupied by electronics without significantly degrading energy and spatial resolution.

  3. Monte Carlo investigation of charge-transport effects on energy resolution and detection efficiency of pixelated CZT detectors for SPECT/PET applications.

    Science.gov (United States)

    Myronakis, Marios E; Darambara, Dimitra G

    2011-01-01

    Semiconductor detectors are increasingly considered as alternatives to scintillation crystals for nuclear imaging applications such as positron emission tomography (PET) or single photon emission computed tomography (SPECT). One of the most prominent detector materials is cadmium zinc telluride (CZT), which is currently used in several application-specific nuclear imaging systems. In this work, the charge-transport effects in pixelated CZT detectors in relation to detector pixel size and thickness are investigated for pixels sizes from 0.4 up to 1.6 mm. The determination of an optimum pixel size and thickness for use with photon energies of 140 and 511 keV, suitable for SPECT and PET studies, is attempted using photon detection efficiency and energy resolution as figures of merit. The Monte Carlo method combined with detailed finite element analysis was utilized to realistically model photon interactions in the detector and the signal generation process. The GEANT4 Application for Tomographic Emission (GATE) toolkit was used for photon irradiation and interaction simulations. The COMSOL MULTIPHYSICS software application was used to create finite element models of the detector that included charge drift, diffusion, trapping, and generation. Data obtained from the two methods were combined to generate accurate signal induction at the detector pixels. The energy resolution was calculated as the full width at half maximum of the energy spectrum photopeak. Photon detection efficiency was also calculated. The effects of charge transport within the detector and photon escape from primary pixel of interaction were investigated; the extent of diffusion to lateral pixels was also assessed. Charge transport and signal induction were affected by the position of a pixel in the detector. Edge and corner pixels were less susceptible to lateral diffusion than pixels located in the inner part of the detector. Higher detection efficiency and increased photon escape from primary

  4. Low-energy CZT detector array for the ASIM mission

    DEFF Research Database (Denmark)

    Cenkeramaddi, Linga Reddy; Genov, Georgi; Kohfeldt, Anja

    2012-01-01

    In this article we introduce the low-energy CZT (CdZnTe) 16 384-pixel detector array on-board the Atmosphere Space Interaction Monitor (ASIM), funded by the European Space Agency. This detector is a part of the larger Modular X-and Gamma-ray sensor (MXGS). The CZT detector array is sensitive...

  5. Cathode depth sensing in CZT detectors

    Science.gov (United States)

    Hong, JaeSub; Bellm, Eric C.; Grindlay, Jonathan E.; Narita, Tomohiko

    2004-02-01

    Measuring the depth of interaction in thick Cadmium-Zinc-Telluride (CZT) detectors allows improved imaging and spectroscopy for hard X-ray imaging above 100 keV. The Energetic X-ray Imaging Survey Telescope (EXIST) will employ relatively thick (5 - 10 mm) CZT detectors, which are required to perform the broad energy-band sky survey. Interaction depth information is needed to correct events to the detector "focal plane" for correct imaging and can be used to improve the energy resolution of the detector at high energies by allowing event-based corrections for incomplete charge collection. Background rejection is also improved by allowing low energy events from the rear and sides of the detector to be rejected. We present experimental results of intereaction depth sensing in a 5 mm thick pixellated Au-contact IMARAD CZT detector. The depth sensing was done by making simultaneous measurements of cathode and anode signals, where the interaction depth at a given energy is proportional to the ratio of cathode/anode signals. We demonstrate how a simple empirical formula describing the event distributions in the cathode/anode signal space can dramatically improve the energy resolution. We also estimate the energy and depth resolution of the detector as a function of the energy and the interaction depth. We also show a depth-sensing prototype system currently under development for EXIST in which cathode signals from 8, 16 or 32 crystals can be read-out by a small multi-channel ASIC board that is vertically edge-mounted on the cathode electrode along every second CZT crystal boundary. This allows CZT crystals to be tiled contiguously with minimum impact on throughput of incoming photons. The robust packaging is crucial in EXIST, which will employ very large area imaging CZT detector arrays.

  6. Background Measurements from Balloon-Borne CZT Detectors

    OpenAIRE

    Jenkins, Johnathan A; Narita, Tomohiko; Grindlay, Jonathan E.; Bloser, Peter F.; Stahle, Carl; Parker, Brad; Barthelmy, Scott

    2002-01-01

    We report detector characteristics and background measurements from two prototype imaging CZT detectors flown on a scientific balloon payload in May 2001. The detectors are both platinum-contact 10mm x 10mm x 5mm CZT crystals, each with a 4 $\\times$ 4 array of pixels tiling the anode. One is made from IMARAD horizontal Bridgman CZT, the other from eV Products high-pressure Bridgman material. Both detectors were mounted side-by-side in a flip-chip configuration and read out by a 32-channel IDE...

  7. Characterization of CZT Detectors for the ASIM Mission

    DEFF Research Database (Denmark)

    Budtz-Jørgensen, Carl; Kuvvetli, Irfan; Skogseide, Y.

    2009-01-01

    The National Space Institute, of the Technical University of Denmark is responsible for the selection and characterization of the CZT detector crystals for the X- and Gamma-ray instrument, MXGS, onboard ESA's Atmospheric Space Interaction Monitor (ASIM) mission. The first CZT pixel detector modules...... for MXGS have recently been delivered by Redlen. Measurements at the University of Bergen demonstrate that the detectors exhibit the expected spectral performance; however, it was also found that the detector modules showed unexplained pixel-to-pixel count rate variations. At The National Space Institute...

  8. CZT imaging detectors for ProtoEXIST

    CERN Document Server

    Hong, J; Chammas, N; Copete, A; Baker, R G; Barthelmy, S D; Gehrels, N; Cook, W R; Burnham, J A; Harrison, F A; Collins, J; Craig, W W

    2006-01-01

    We describe the detector development for a balloon-borne wide-field hard X-ray (20 - 600 keV) telescope, ProtoEXIST. ProtoEXIST is a pathfinder for both technology and science of the proposed implementation of the Black Hole Finder Probe, Energetic X-ray Imaging Survey telescope (EXIST). The principal technology challenge is the development of large area, close-tiled modules of imaging CZT detectors (1000 cm2 for ProtoEXIST1). We review the updates of the detector design and package concept for ProtoEXIST1 and report the current development status of the CZT detectors, using calibration results of our basic detector unit - 2 x 2 x 0.5 cm CZT crystals with 2.5 mm pixels (8 x 8 array). The current prototype (Rev1) of our detector crystal unit (DCU) shows ~4.5 keV electronics noise (FWHM), and the radiation measurements show the energy resolution (FWHM) of the units is 4.7 keV (7.9%) at 59.5 keV, 5.6 keV (4.6%) at 122 keV, and 7.6 keV (2.1%) at 356 keV. The new (Rev2) DCU with revised design is expected to impro...

  9. Cathode depth sensing in CZT detectors

    CERN Document Server

    Hong, J; Grindlay, J E; Narita, T

    2003-01-01

    Measuring the depth of interaction in thick Cadmium-Zinc-Telluride (CZT) detectors allows improved imaging and spectroscopy for hard X-ray imaging above 100 keV. The Energetic X-ray Imaging Survey Telescope (EXIST) will employ relatively thick (5 - 10 mm) CZT detectors, which are required to perform the broad energy-band sky survey. Interaction depth information is needed to correct events to the detector "focal plane" for correct imaging and can be used to improve the energy resolution of the detector at high energies by allowing event-based corrections for incomplete charge collection. Background rejection is also improved by allowing low energy events from the rear and sides of the detector to be rejected. We present experimental results of interaction depth sensing in a 5 mm thick pixellated Au-contact IMARAD CZT detector. The depth sensing was done by making simultaneous measurements of cathode and anode signals, where the interaction depth at a given energy is proportional to the ratio of cathode/anode ...

  10. Continued Development of Small-Pixel CZT and CdTe Detectors for Future High-Angular-Resolution Hard X-ray Missions

    Science.gov (United States)

    Krawczynski, Henric

    The Nuclear Spectroscopic Telescope Array (NuSTAR) Small Explorer Mission was launched in June 2012 and has demonstrated the technical feasibility and high scientific impact of hard X-ray astronomy. We propose to continue our current R&D program to develop finely pixelated semiconductor detectors and the associated readout electronics for the focal plane of a NuSTAR follow-up mission. The detector-ASIC (Application Specific Integrated Circuit) package will be ideally matched to the new generation of low-cost, low-mass X-ray mirrors which achieve an order of magnitude better angular resolution than the NuSTAR mirrors. As part of this program, the Washington University group will optimize the contacts of 2x2 cm^2 footprint Cadmium Zinc Telluride (CZT) and Cadmium Telluride (CdTe) detectors contacted with 100x116 hexagonal pixels at a next-neighbor pitch of 200 microns. The Brookhaven National Laboratory group will design, fabricate, and test the next generation of the HEXID ASIC matched to the new X-ray mirrors and the detectors, providing a low-power 100x116 channel ASIC with extremely low readout noise (i.e. with a root mean square noise of 13 electrons). The detectors will be tested with radioactive sources and in the focal plane of high-angular-resolution X-ray mirrors at the X-ray beam facilities at the Goddard and Marshall Space Flight Centers.

  11. Pixel Detectors

    OpenAIRE

    Wermes, Norbert

    2005-01-01

    Pixel detectors for precise particle tracking in high energy physics have been developed to a level of maturity during the past decade. Three of the LHC detectors will use vertex detectors close to the interaction point based on the hybrid pixel technology which can be considered the state of the art in this field of instrumentation. A development period of almost 10 years has resulted in pixel detector modules which can stand the extreme rate and timing requirements as well as the very harsh...

  12. CZT Detector Development for Hard X-ray Astronomy

    Science.gov (United States)

    Garson, Alfred, III; Li, Q.; Beilicke, M.; Bose, R.; Burger, A.; Dowkonnt, P.; Groza, M.; Simburger, G.; Krawczynski, H.

    2008-05-01

    Cadmium Zinc Telluride (CZT) has proven itself as an excellent material for detection of hard X-rays. Advances in crystal growth have increased the quality and size of available single CZT crystals. We report on our ongoing development and characterization of CZT detector systems. With our dedicated class-100 cleanroom, we fabricate detectors using CZT crystals from different manufactures. Using photolithography and e-beam evaporation, we can produce detectors with different contact designs (pixellated, strip, monolithic, steering grid), contact dimensions (down to 50 microns), and contact materials (In, Ti, Au, etc.) . In addition, we develop ASIC readouts for various CZT detector applications, including our characterization of the detectors. We measure I-V and C-V curves for the detectors as well as their spectroscopic performance. We compare measured results with those from detailed modelling and simulations. The CZT detector systems can then be optimized for applications such as X-ray imaging and polarimetry with satellite or balloon-borne instruments.

  13. Leakage Currents and Capacitances of Thick CZT Detectors

    OpenAIRE

    Garson III, Alfred; Li, Qiang; Jung, Ira V.; Dowkontt, Paul; Bose, Richard; Simburger, Garry; Krawczynski, Henric

    2009-01-01

    The quality of Cadmium Zinc Telluride (CZT) detectors is steadily improving. For state of the art detectors, readout noise is thus becoming an increasingly important factor for the overall energy resolution. In this contribution, we present measurements and calculations of the dark currents and capacitances of 0.5 cm-thick CZT detectors contacted with a monolithic cathode and 8x8 anode pixels on a surface of 2 cm x 2 cm. Using the NCI ASIC from Brookhaven National Laboratory as an example, we...

  14. Compton imaging with thick Si and CZT detectors

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, Mythili, E-mail: mythili.subramanian@gmail.com [George Mason University, 4400 University Dr., Fairfax, VA 22030 (United States); Wulf, Eric A.; Phlips, Bernard [U S Naval Research Lab, 4555 Overlook Ave SW, Washington DC 20375 (United States); Krawczynski, Henric; Martin, Jerrad; Dowknott, Paul [Washington University at St. Louis, St. Louis. MO (United States)

    2012-08-01

    A Compton imaging telescope has been constructed using a 0.2 cm thick Silicon (Si) detector of active area 9.0 Multiplication-Sign 9.0 cm{sup 2} and a pixelated Cadmium Zinc Telluride (CZT) detector of dimensions 2.0 Multiplication-Sign 2.0 Multiplication-Sign 0.5 cm{sup 3}. The Si detector is double sided with 64 strips per side in two orthogonal directions. The CZT detector has 64 pixels of pitch 0.25 cm. We used several ASICs (32 channel) to read out both detectors. A {sup 137}Cs source was used in the study. The energy deposited in the Si and CZT detectors and the points of interaction of the {gamma}-ray in both detectors were read out. We varied the position of the source as well as the vertical separation between the Si and CZT detectors and measured the angular resolution of the source image for the different configurations. The best angular resolution (1{sigma}) was 2.4 Degree-Sign . Monte Carlo simulations were run for similar detector configurations and agree with the experimental results.

  15. Leakage Currents and Capacitances of Thick CZT Detectors

    CERN Document Server

    Garson, Alfred; Jung, Ira V; Dowkontt, Paul; Bose, Richard; Simburger, Garry; Krawczynski, Henric

    2009-01-01

    The quality of Cadmium Zinc Telluride (CZT) detectors is steadily improving. For state of the art detectors, readout noise is thus becoming an increasingly important factor for the overall energy resolution. In this contribution, we present measurements and calculations of the dark currents and capacitances of 0.5 cm-thick CZT detectors contacted with a monolithic cathode and 8x8 anode pixels on a surface of 2 cm x 2 cm. Using the NCI ASIC from Brookhaven National Laboratory as an example, we estimate the readout noise caused by the dark currents and capacitances. Furthermore, we discuss possible additional readout noise caused by pixel-pixel and pixel-cathode noise coupling.

  16. Pixel detectors

    CERN Document Server

    Passmore, M S

    2001-01-01

    positions on the detector. The loss of secondary electrons follows the profile of the detector and increases with higher energy ions. studies of the spatial resolution predict a value of 5.3 lp/mm. The image noise in photon counting systems is investigated theoretically and experimentally and is shown to be given by Poisson statistics. The rate capability of the LAD1 was measured to be 250 kHz per pixel. Theoretical and experimental studies of the difference in contrast for ideal charge integrating and photon counting imaging systems were carried out. It is shown that the contrast differs and that for the conventional definition (contrast = (background - signal)/background) the photon counting device will, in some cases, always give a better contrast than the integrating system. Simulations in MEDICI are combined with analytical calculations to investigate charge collection efficiencies (CCE) in semiconductor detectors. Different pixel sizes and biasing conditions are considered. The results show charge shari...

  17. Background Measurements from Balloon-Borne CZT Detectors

    CERN Document Server

    Jenkins, J A; Grindlay, J E; Bloser, P F; Stahle, C K; Parker, B; Barthelmy, S D; Jenkins, Johnathan A; Narita, Tomohiko; Grindlay, Jonathan E.; Bloser, Peter F.; Stahle, Carl; Parker, Brad; Barthelmy, Scott

    2002-01-01

    We report detector characteristics and background measurements from two prototype imaging CZT detectors flown on a scientific balloon payload in May 2001. The detectors are both platinum-contact 10mm x 10mm x 5mm CZT crystals, each with a 4 $\\times$ 4 array of pixels tiling the anode. One is made from IMARAD horizontal Bridgman CZT, the other from eV Products high-pressure Bridgman material. Both detectors were mounted side-by-side in a flip-chip configuration and read out by a 32-channel IDE VA/TA ASIC preamp/shaper. We enclosed the detectors in the same 40deg field-of-view collimator (comprisinga graded passive shield and plastic scintillator) used in our previously-reported September 2000 flight. I-V curves for the detectors are diode-like, and we find that the platinum contacts adhere significantly better to the CZT surfaces than gold to previous detectors. The detectors and instrumentation performed well in a 20-hour balloon flight on 23/24 May 2001. Although we discovered a significant instrumental back...

  18. Performance Characteristics of Pixelated CZT Crystals used on the GammaTracker Project

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Eric M.; Seifert, Carolyn E.; Myjak, Mitchell J.; Erikson, Luke E.; Morris, Scott J.; Balvage, Duane R.; Lundy, Richard P.

    2011-08-21

    GammaTracker is a handheld radioisotope identification device in development at Pacific Northwest National Laboratory that uses eighteen pixelated Cadmium-Zinc Telluride (CZT) crystals to provide energy resolution approaching that of high-purity germanium without the need for cryogenic cooling. Additionally, these crystals can be used to provide directional and imaging capabilities that cannot be found in other handheld detectors. A significant number of CZT crystals have been procured during the development of the GammaTracker system; the majority of these were procured with the same set of specifications. Each of these detectors has been characterized in terms of key parameters, including current-voltage response and pixel-by-pixel energy resolution. The results of this testing indicate that the overall quality of CZT crystals is improving over time.

  19. Measurements of Charge Sharing Effects in Pixilated CZT/CdTe Detectors

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl

    2007-01-01

    Te pixel detector samples. The results are used for the development of the large area X-ray and Gamma ray detector for the Atmosphere-Space Interactions Monitor (ASIM) planned for the ISS ESA Columbus module. Charge sharing measurements on detector samples with identical size and pixel geometry......In this paper, charge sharing and charge loss effects in pixilated CZT/CdTe detectors are investigated by measurements. We measured charge sharing effects function of the inter-pixel gap (with same pixel pitch), the photon energy and the detector bias voltage for a large numbers of CZT and Cd...

  20. Background measurements from balloon-born imaging CZT detectors

    Science.gov (United States)

    Jenkins, Jonathan A.; Narita, Tomohiko; Grindlay, Jonathan E.; Bloser, Peter F.; Stahle, Carl M.; Parker, Bradford H.; Barthelmy, Scott D.

    2003-03-01

    We report detector characteristics and background measurements from two prototype imaging CdZnTe (CZT) detectors flown on a scientific balloon payload in May 2001. The detectors are both platinum-contact 10 mm × 10 mm × 5 mm CZT crystals, each with a 4 × 4 array of pixels tiling the anode. One is made from IMARAD horizontal Bridgman CZT, the other from eV Products high-pressure Bridgman CZT. Both detectors were mounted side-by-side in a flip-chip configuration and read out by a 32-channel IDE VA/TA ASIC preamp/shaper. We enclosed the detectors in the same 40o field-of-view collimator used in our previously-reported September 2000 flight. I-V curves for the detectors are diode-like, and we find that the platinum contacts adhere significantly better to the CZT surfaces than gold to previosu detectors. The detectors and instrumentation performed well in a 20-hour balloon flight on 23/24 May 2001. Although we discovered a significant instrumental background component in flight, it was possible to measure and subtract this component from the spectra. The resulting IMARAD detector background spectrum reaches ~5×10-3 counts cm-2s-1keV-1 at 100 keV and has a power-law index of ~2 at hgih energies. The eV Products detector has a similar spectrum, although there is more uncertainty in the enregy scale because of calibration complications.

  1. Cathode depth sensing in CZT detectors

    OpenAIRE

    Hong, J; Bellm, E.C.; Grindlay, J.E.; Narita, T

    2003-01-01

    Measuring the depth of interaction in thick Cadmium-Zinc-Telluride (CZT) detectors allows improved imaging and spectroscopy for hard X-ray imaging above 100 keV. The Energetic X-ray Imaging Survey Telescope (EXIST) will employ relatively thick (5 - 10 mm) CZT detectors, which are required to perform the broad energy-band sky survey. Interaction depth information is needed to correct events to the detector "focal plane" for correct imaging and can be used to improve the energy resolution of th...

  2. Pixelated CdZnTe drift detectors

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl

    2005-01-01

    A technique, the so-called Drift Strip Method (DSM), for improving the CdZnTe detector energy response to hard X-rays and gamma-rays was applied as a pixel geometry. First tests have confirmed that this detector type provides excellent energy resolution and imaging performance. We specifically...... report on the performance of 3 mm thick prototype CZT drift pixel detectors fabricated using material from eV-products. We discuss issues associated with detector module performance. Characterization results obtained from several prototype drift pixel detectors are presented. Results of position...

  3. Position-sensitive CZT detector module

    Science.gov (United States)

    Matteson, James L.; Duttweiler, Fred; Huszar, George L.; Leblanc, Philippe C.; Skelton, Robert E.; Stephan, Edwin A.; Hink, Paul L.; Dowkontt, Paul F.; Slavis, Kimberly R.; Tumer, Tumay O.; Kravis, Scott D.

    1998-07-01

    Coded mask imagers for future high energy x-ray astronomy missions will require detector planes with areas of hundreds to thousands of cm(superscript 2) and position resolutions CZT detector systems with crossed-strip readout to meet these requirements. We report progress on a compact detector module with 41 cm(superscript 2) area and 0.5 mm spatial resolution. The design includes the bias network and ASIC readout electronics, and allows modules to be combined in large area arrays with very high live-area factors. Results from laboratory and balloon flight tests are presented.

  4. Balloon Flight Background Measurement with Actively-Shielded Planar and Imaging CZT Detectors

    CERN Document Server

    Bloser, P F; Jenkins, J A; Perrin, M; Murray, R; Grindlay, J E

    2001-01-01

    We present results from the flight of two prototype CZT detectors on a scientific balloon payload in September 2000. The first detector, referred to as ``CZT1,'' consisted of a 10 mm x 10 mm x 2 mm CZT crystal with a single gold planar electrode readout. This detector was shielded by a combination of a passive collimator surrounded by plastic scintillator and a thick BGO crystal in the rear. The second detector, ``CZT2,'' comprised two 10 mm x 10 mm x 5 mm CZT crystals, one made of eV Products high pressure Bridgman material and the other of IMARAD horizontal Bridgman material, each fashioned with a 4 x 4 array of gold pixels on a 2.5 mm pitch. The pixellated detectors were flip-chip-mounted side by side and read out by a 32-channel ASIC. This detector was also shielded by a passive/plastic collimator in the front, but used only additional passive/plastic shielding in the rear. Both experiments were flown from Ft. Sumner, NM on September 19, 2000 on a 24 hour balloon flight. CZT1 recorded a non-vetoed backgro...

  5. Development of CZT detectors for x-ray and gamma-ray astronomy

    Science.gov (United States)

    Lee, Kuen; Martin, J. W.; Garson, A., III; Guo, Q.; Matteson, J.; Groza, M.; Beilicke, M.; Burger, A.; de Geronimo, G.; Krawczynski, H.

    2011-09-01

    Cadmium Zinc Telluride (CZT) is the detector material of choice for the detection of X-rays in the 10 keV-1MeV energy band with excellent spatial and energy resolutions and without cryogenic cooling. In this contribution, we report on recent results of the CZT detector development program and several astrophysical experiments which make use of CZT detectors. In the first part of the paper, we discuss the performance of pixel and cross-strip CZT detectors read out with an ASIC developed at the Brookhaven National Laboratory. Our pixel detectors achieve some of the best energy resolutions reported in the literature. Cross-strip detectors are found to give an inferior performance and we investigate the reason for this performance difference. We also present results from a precision measurement of the effect of a steering grid on multi-pixel events obtained with a 200 micrometer collimator. In the second part of the paper, we describe the design and performance of the hard X-ray polarimeter X-Calibur. The polarimeter uses a 14 cm long scintillator scatterer, surrounded by an assembly of 32 2-5 mm thick CZT detectors. We discuss the sensitivity of the polarimeter to measure the linear polarization of 10 keV-80 keV X-rays on short and long balloon flights and results from testing the polarimeter in the laboratory.

  6. Characterisation of a CZT detector for dosimetry of molecular radiotherapy

    Science.gov (United States)

    McAreavey, L. H.; Harkness-Brennan, L. J.; Colosimo, S. J.; Judson, D. S.; Boston, A. J.; Boston, H. C.; Nolan, P. J.; Flux, G. D.; Denis-Bacelar, A. M.; Harris, B.; Radley, I.; Carroll, M.

    2017-03-01

    A pixelated cadmium zinc telluride (CZT) detector has been characterised for the purpose of developing a quantitative single photon emission computed tomography (SPECT) system for dosimetry of molecular radiotherapy (MRT). This is the aim of the Dosimetric Imaging with CZT (DEPICT) project, which is a collaboration between the University of Liverpool, The Royal Marsden Hospital, The Royal Liverpool and Broadgreen University Hospital, and the commercial partner Kromek. CZT is a direct band gap semiconductor with superior energy resolution and stopping power compared to scintillator detectors used in current SPECT systems. The inherent detector properties have been investigated and operational parameters such as bias voltage and peaking time have been selected to optimise the performance of the system. Good energy resolution is required to discriminate γ-rays that are scattered as they are emitted from the body and within the collimator, and high photon throughput is essential due to the high activities of isotopes administered in MRT. The system has an average measured electronic noise of 3.31 keV full width at half maximum (FWHM), determined through the use of an internal pulser. The energy response of the system was measured across the energy region of interest 59.5 keV to 364.5 keV and found to be linear. The reverse bias voltage and peaking time producing the optimum FWHM and maximum photon throughput were 600 V and 0.5 μs respectively. The average dead time of the system was measured as 4.84 μs and charge sharing was quantified to be 0.71 % at 59.5 keV . A pixel sensitivity calibration map was created and planar images of the medical imaging isotopes 99mTc and 123I were acquired by coupling the device to a prototype collimator, thereby demonstrating the suitability of the detector for the DEPICT project.

  7. Balloon flight background measurement with actively-shielded planar and imaging CZT detectors

    Science.gov (United States)

    Bloser, Peter F.; Narita, Tomohiko; Jenkins, Jonathan A.; Perrin, Marshall; Murray, Ruth; Grindlay, Jonathan E.

    2002-01-01

    We present results from the flight of two prototype CZT detectors on a scientific balloon payload in September 2000. The first detector, referred to as CZT1, consisted of a 10 mm x 10 mm x 2 mm CZT crystal with a single gold planar electrode readout. This detector was shielded by a combination of a passive collimator in the front, giving a 40 degree field of view and surrounded by plastic scintillator, and a thick BGO crystal in the rear. The second detector, CZT2, comprised two 10 mm x 10 mm x 5 mm CZT crystals, one made of eV Products high pressure Bridgman material and the other of IMARAD horizontal Bridgman material, each fashioned with a 4 x 4 array of gold pixels on a 2.5 mm pitch. The pixellated detectors were flip-chip-mounted side by side and read out by a 32-channel ASIC. This detector was also shielded by a passive/plastic collimator in the front, but used only additional passive/plastic shielding in the rear. Both experiments were flown from Ft. Sumner, NM on September 19, 2000 on a 24 hour balloon flight. Both instruments performed well. CZT1 recorded a non-vetoed background level at 100 keV of approximately 1 x 10-3 cm-2s-1keV-1. Raising the BGO threshold from 50 keV to approximately 1 MeV produced only an 18% increase in this level. CZT2 recorded a background at 100 keV of approximately 4 times 10-3 cts cm-2s-1keV-1 in the eV Products detector and approximately 6 x 10-3 cts cm-2s-1keV-1 in the IMARAD detector, a difference possibly due to our internal background subtracting procedure. Both CZT1 and CZT2 spectra were in basic agreement with Monte Carlo simulations, though both recorded systematically higher count rates at high energy than predicted. No lines were observed, indicating that neutron capture reactions, at least those producing decay lines at a few 100 keV, are not significant components of the CZT background. Comparison of the CZT1 and CZT2 spectra indicates that passive/plastic shielding may provide adequately low background levels for

  8. Pixel Vertex Detectors

    OpenAIRE

    Wermes, Norbert

    2006-01-01

    Pixel vertex detectors are THE instrument of choice for the tracking of charged particles close to the interaction point at the LHC. Hybrid pixel detectors, in which sensor and read-out IC are separate entities, constitute the present state of the art in detector technology. Three of the LHC detectors use vertex detectors based on this technology. A development period of almost 10 years has resulted in pixel detector modules which can stand the extreme rate and timing requirements as well as ...

  9. Development of large-area CZT detector systems

    Science.gov (United States)

    Kuvvetli, Irfan; Budtz-Joergensen, Carl C.; Westergaard, Niels J.; Jonasson, Per; van Pamelen, Mike A.; Reglero, Victor; Eyles, Christopher J.; Neubert, Torsten

    1999-10-01

    DSRI has initiated a development program of CZT x-ray and gamma ray detectors employing strip readout techniques. A dramatic improvement of the energy response was found operating the detectors as so-called drift detectors. For the electronic readout, modern ASIC chips were investigated. Modular design and the low power electronics will make large area detectors using the drift strip method feasible. The performance of a prototype CZT system will be presented and discussed.

  10. Improved x-ray spectroscopy with room temperature CZT detectors.

    Science.gov (United States)

    Fritz, Shannon G; Shikhaliev, Polad M; Matthews, Kenneth L

    2011-09-07

    Compact, room temperature x-ray spectroscopy detectors are of interest in many areas including diagnostic x-ray imaging, radiation protection and dosimetry. Room temperature cadmium zinc telluride (CZT) semiconductor detectors are promising candidates for these applications. One of the major problems for CZT detectors is low-energy tailing of the energy spectrum due to hole trapping. Spectral post-correction methods to correct the tailing effect do not work well for a number of reasons; thus it is advisable to eliminate the hole trapping effect in CZT using physical methods rather than correcting an already deteriorated energy spectrum. One method is using a CZT detector with an electrode configuration which modifies the electric field in the CZT volume to decrease low-energy tailing. Another method is to irradiate the CZT surface at a tilted angle, which modifies depth of interaction to decrease low-energy tailing. Neither method alone, however, eliminates the tailing effect. In this work, we have investigated the combination of modified electric field and tilted angle irradiation in a single detector to further decrease spectral tailing. A planar CZT detector with 10 × 10 × 3 mm³ size and CZT detector with 5 × 5 × 5 mm³ size and cap-shaped electrode were used in this study. The cap-shaped electrode (referred to as CAPture technology) modifies the electric field distribution in the CZT volume and decreases the spectral tailing effect. The detectors were investigated at 90° (normal) and 30° (tilted angle) irradiation modes. Two isotope sources with 59.6 and 122 keV photon energies were used for gamma-ray spectroscopy experiments. X-ray spectroscopy was performed using collimated beams at 60, 80 and 120 kVp tube voltages, in both normal and tilted angle irradiation. Measured x-ray spectra were corrected for K x-ray escape fractions that were calculated using Monte Carlo methods. The x-ray spectra measured with tilted angle CAPture detector at 60, 80 and 120

  11. Multi-Material Decomposition using Low-Current X-Ray and a Photon-Counting CZT Detector

    OpenAIRE

    Kim, Sangtaek; Hernandez, Andrew; Alhassen, Fares; Pivovaroff, Michael; Cho, Hyo-Min; Gould, Robert G.; Seo, Youngho

    2011-01-01

    We developed and evaluated an x-ray photon-counting imaging system using an energy-resolving cadmium zinc telluride (CZT) detector coupled with application specific integrated circuit (ASIC) readouts. This x-ray imaging system can be used to identify different materials inside the object. The CZT detector has a large active area (5×5 array of 25 CZT modules, each with 16×16 pixels, cover a total area of 200 mm × 200 mm), high stopping efficiency for x-ray photons (~ 100 % at 60 keV and 5 mm t...

  12. The pixelated detector

    CERN Multimedia

    Sutton, C

    1990-01-01

    "Collecting data as patterns of light or subatomic particles is vitally important in all the sciences. The new generation of solid-state detectors called pixel devices could transform experimental research at all levels" (4 pages).

  13. A new design for a high resolution, high efficiency CZT gamma camera detector

    Science.gov (United States)

    Mestais, C.; Baffert, N.; Bonnefoy, J. P.; Chapuis, A.; Koenig, A.; Monnet, O.; Ouvrier Buffet, P.; Rostaing, J. P.; Sauvage, F.; Verger, L.

    2001-02-01

    We have designed a CZT gamma camera detector that provides an array of CZT pixels and associated front-end electronics - including an ASIC - and permits gamma camera measurements using the method patented by CEA-LETI and reported by Verger et al. [1]. Electron response in each CZT pixel is registered by correcting pulse height for position of interaction based on fast rise-time information. This method brings advantages of high scatter rejection while allowing high detection efficiency. These techniques and the systems approach have been developed at CEA-LETI in an exclusive joint development with BICRON and CRISMATEC who in turn are commercializing the technology. The initial system is implemented in an array framework with 1920 pixels, approximately 180×215 mm 2 in dimension, but the system architecture expands readily to 4096 pixels, and these arrays can be ganged into groups of up to 8 for pixel planes totaling over 32 000 pixels without architecture changes. The overall system design is described and brain phantom images are presented that were obtained by scanning with a small number of pixels.

  14. CZT drift strip detectors for high energy astrophysics

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Caroli, E.

    2010-01-01

    Requirements for X- and gamma ray detectors for future High Energy Astrophysics missions include high detection efficiency and good energy resolution as well as fine position sensitivity even in three dimensions.We report on experimental investigations on the CZT drift detector developed DTU Space....... It is operated in the planar transverse field (PTF) mode, with the purpose of demonstrating that the good energy resolution of the CZT drift detector can be combined with the high efficiency of the PTF configuration. Furthermore, we demonstrated and characterized the 3D sensing capabilities of this detector...... configuration.The CZT drift strip detector (10mm×10mm×2.5mm) was characterized in both standard illumination geometry, Photon Parallel Field (PPF) configuration and in PTF configuration. The detection efficiency and energy resolution are compared for both configurations . The PTF configuration provided a higher...

  15. Pixel detector readout chip

    CERN Multimedia

    1991-01-01

    Close-up of a pixel detector readout chip. The photograph shows an aera of 1 mm x 2 mm containing 12 separate readout channels. The entire chip contains 1000 readout channels (around 80 000 transistors) covering a sensitive area of 8 mm x 5 mm. The chip has been mounted on a silicon detector to detect high energy particles.

  16. ATLAS ITk Pixel detector

    CERN Document Server

    Gemme, Claudia; The ATLAS collaboration

    2016-01-01

    The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenge to the ATLAS tracker. The current inner detector will be replaced with a whole silicon tracker which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation level are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the HL-LHC ATLA Pixel detector developments as well as the various layout options will be reviewed.

  17. Multi-Material Decomposition using Low-Current X-Ray and a Photon-Counting CZT Detector.

    Science.gov (United States)

    Kim, Sangtaek; Hernandez, Andrew; Alhassen, Fares; Pivovaroff, Michael; Cho, Hyo-Min; Gould, Robert G; Seo, Youngho

    2011-01-01

    We developed and evaluated an x-ray photon-counting imaging system using an energy-resolving cadmium zinc telluride (CZT) detector coupled with application specific integrated circuit (ASIC) readouts. This x-ray imaging system can be used to identify different materials inside the object. The CZT detector has a large active area (5×5 array of 25 CZT modules, each with 16×16 pixels, cover a total area of 200 mm × 200 mm), high stopping efficiency for x-ray photons (~ 100 % at 60 keV and 5 mm thickness). We explored the performance of this system by applying different energy windows around the absorption edges of target materials, silver and indium, in order to distinguish one material from another. The photon-counting CZT-based x-ray imaging system was able to distinguish between the materials, demonstrating its capability as a radiation-spectroscopic decomposition system.

  18. Noise Analysis of Array Pixellated CZT Detector%CZT像素阵列核探测器的噪声分析

    Institute of Scientific and Technical Information of China (English)

    蒋建; 肖沙里; 蔡欣; 张流强; 陈宇晓; 曹玉琳

    2011-01-01

    碲锌镉(CdZnTe)晶体是一种新型核辐射探测材料,在室温探测环境下对X射线及低能量伽玛射线具有较高的探测效率及能量分辨率.运用低噪声快速前放模块,分析晶体内部性能以及前置放大器对探测系统噪声的影响,建立了2×2碲锌镉像素阵列探测系统.实验结果表明,探测系统输出信号噪声小、脉冲无堆积,读出电路电子学噪声得到明显抑制,能谱低能拖尾减少,电荷收集不完全噪声及漏电流噪声影响得到改善,同时对整个系统以及前置放大器进行了噪声分析并提出相关的改善方式,最后得到系统测试的结果.%As a novel nuclear radiation material, CdZnTe has many advantages of high effi ciency detection and good energy resolution for detection of x-ray and low energy gamma-ray in room temperature. The inner crystal property and effects of preamplifier on the noise is analyzed using low noise preamplifier module, while a 2× 2 array pixellated detection system is built. The results show a low noise of output signal and no pulse stack. The circuit electronic noise is obvi ously restrained. Trails of low power of energy spectrum are decreased. Noise analysis and the factors which produced the noise are given; improvement for the system is also discussed, togeth er with the test result.

  19. Pixel detector insertion

    CERN Multimedia

    CMS

    2015-01-01

    Insertion of the Pixel Tracker, the 66-million-channel device used to pinpoint the vertex of each colliding proton pair, located at the heart of the detector. The geometry of CMS is a cylinder lying on its side (22 meters long and 15 meters high in dia

  20. ALICE Silicon Pixel Detector

    CERN Multimedia

    Manzari, V

    2013-01-01

    The Silicon Pixel Detector (SPD) forms the innermost two layers of the 6-layer barrel Inner Tracking System (ITS). The SPD plays a key role in the determination of the position of the primary collision and in the reconstruction of the secondary vertices from particle decays.

  1. Modelling semiconductor pixel detectors

    CERN Document Server

    Mathieson, K

    2001-01-01

    expected after 200 ps in most cases. The effect of reducing the charge carrier lifetime and examining the charge collection efficiency has been utilised to explore how these detectors would respond in a harsh radiation environment. It is predicted that over critical carrier lifetimes (10 ps to 0.1 ns) an improvement of 40 % over conventional detectors can be expected. This also has positive implications for fabricating detectors, in this geometry, from materials which might otherwise be considered substandard. An analysis of charge transport in CdZnTe pixel detectors has been performed. The analysis starts with simulation studies into the formation of contacts and their influence on the internal electric field of planar detectors. The models include a number of well known defect states and these are balanced to give an agreement with a typical experimental I-V curve. The charge transport study extends to the development of a method for studying the effect of charge sharing in highly pixellated detectors. The ...

  2. Balloon Flight Background Measurement with Actively-Shielded Planar and Imaging CZT Detectors

    OpenAIRE

    Bloser, P. F.; Narita, T; Jenkins, J. A.; Perrin, M.; Murray, R.; Grindlay, J.E.

    2001-01-01

    We present results from the flight of two prototype CZT detectors on a scientific balloon payload in September 2000. The first detector, referred to as ``CZT1,'' consisted of a 10 mm x 10 mm x 2 mm CZT crystal with a single gold planar electrode readout. This detector was shielded by a combination of a passive collimator surrounded by plastic scintillator and a thick BGO crystal in the rear. The second detector, ``CZT2,'' comprised two 10 mm x 10 mm x 5 mm CZT crystals, one made of eV Product...

  3. CZT Virtual Frisch-grid Detector: Principles and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Cui,Y.; Bolotnikov, A.; Camarda, G.; Hossain, A.; James, R. B.

    2009-03-24

    Cadmium Zinc Telluride (CdZnTe or CZT) is a very attractive material for using as room-temperature semiconductor detectors, because it has a wide bandgap and a high atomic number. However, due to the material's poor hole mobility, several special techniques were developed to ensure its suitability for radiation detection. Among them, the virtual Frisch-grid CZT detector is an attractive option, having a simple configuration, yet delivering an outstanding spectral performance. The goal of our group in Brookhaven National Laboratory (BNL) is to improve the performance of Frisch-ring CZT detectors; most recently, that effort focused on the non-contacting Frisch-ring detector, allowing us to build an inexpensive, large-volume detector array with high energy-resolution and a large effective area. In this paper, the principles of virtual Frisch-grid detectors are described, especially BNL's innovative improvements. The potential applications of virtual Frisch-grid detectors are discussed, and as an example, a hand-held gamma-ray spectrometer using a CZT virtual Frischgrid detector array is introduced, which is a self-contained device with a radiation detector, readout circuit, communication circuit, and high-voltage supply. It has good energy resolution of 1.4% (FWHM of 662-keV peak) with a total detection volume of {approx}20 cm{sup 3}. Such a portable inexpensive device can be used widely in nonproliferation applications, non-destructive detection, radiation imaging, and for homeland security. Extended systems based on the same technology have potential applications in industrial- and nuclear-medical-imaging.

  4. Effects of bulk and surface conductivity on the performance of CdZnTe pixel detectors

    DEFF Research Database (Denmark)

    Bolotnikov, A.E.; Chen, C.M.H.; Cook, W.R.;

    2002-01-01

    between the pixel contacts. When the grid is negatively biased, the strong electric field in the gaps between the pixels forces the electrons landing on the surface to move toward the contacts, preventing the charge loss. We have investigated these effects by using CZT pixel detectors indium bump...

  5. Development of a 3D CZT detector prototype for Laue Lens telescope

    OpenAIRE

    Caroli, Ezio; Auricchio, Natalia; Del Sordo, Stefano; Abbene, Leonardo; Budtz-JøRgensen, Carl; Casini, Fabio; Curado da Silva, Rui M.; Kuvvetli, Irfan; Milano, Luciano; Natalucci, Lorenzo; Quadrini, Egidio M.; Stephen, John B.; Ubertini, Pietro; Zanichelli, Massimiliano; Zappettini, Andrea

    2010-01-01

    We report on the development of a 3D position sensitive prototype suitable as focal plane detector for Laue lens telescope. The basic sensitive unit is a drift strip detector based on a CZT crystal, (~19×8 mm2 area, 2.4 mm thick), irradiated transversally to the electric field direction. The anode side is segmented in 64 strips, that divide the crystal in 8 independent sensor (pixel), each composed by one collecting strip and 7 (one in common) adjacent drift strips. The drift strips are biase...

  6. Alpine Pixel Detector Layout

    CERN Document Server

    Delebecque, P; The ATLAS collaboration; Geffroy, N; Massol, N; Rambure, T; Todorov, T

    2013-01-01

    A description of an optimized layout of pixel sensors based on a stave that combines both barrel and endcap module orientations. The mechanical stiffness of the structure is provided by carbon fiber shells spaced by carbon foam. The cooling of the modules is provided by two-phase $CO_{2}$ flowing in a thin titanium pipe glued inside the carbon fiber foam. The electrical services of all modules are provided by a single stave flex. This layout eliminates the need for separate barrel and endcap detector structures, and therefore the barrel services material in front of the endcap. The transition from barrel to endcap module orientation is optimized separately for each layer in order to minimize the active pixel area and the traversed material. The sparse module spacing in the endcap part of the stave allows for multiple fixation points, and for a stiff overall structure composed only of staves interconnected by stiff disks.

  7. A Readout ASIC for CZT Detectors

    CERN Document Server

    Jones, L

    2008-01-01

    Spectrometers that can identify the energy of gamma radiation and determine the source isotope have until recently used low temperature semiconductors. These require cooling which makes their portability difficult. The material Cadmium Zinc Telluride (CZT) is now available which operates at room temperature and can be used to measure the energy of gamma radiation. In a compton camera configuration the direction of the radiation can also be determined. A read-out ASIC has been developed for such a system and features 100 channels of electronics, each with a charge amplifier, CR-RC shaper, and peak-hold. A 12 bit ADC converts the data which is sparsified before being read out. The energy, signal rise time, and timestamp of any hit channel is read out together with the data from all of its neighbours. The ASIC has a selectable lower dynamic range which could be used for lower energy interactions.

  8. Multipixel characterization of imaging CZT detectors for hard x-ray imaging and spectroscopy

    Science.gov (United States)

    Vadawale, Santosh V.; Hong, Jae Sub; Grindlay, Jonathan E.; Williams, Peter; Zhang, Minhua; Bellm, Eric C.; Narita, Tomohiko; Craig, William W.; Parker, Bradford H.; Stahle, Carl M.; Yan, Feng

    2004-10-01

    We report our in-depth study of Cd-Zn-Te (CZT) crystals to determine an optimum pixel and guard band configuration for Hard X-ray imaging and spectroscopy. We tested 20x20x5mm crystals with 8x8 pixels on a 2.46mm pitch. We have studied different types of cathode / anode contacts and different pixel pad sizes. We present the measurements of leakage current as well as spectral response for each pixel. Our I-V measurement setup is custom designed to allow automated measurements of the I-V curves sequentially for all 64 pixels, whereas the radiation properties measurement setup allows for interchangeable crystals with the same XAIM3.2 ASIC readout from IDEAS. We have tested multiple crystals of each type, and each crystal in different positions to measure the variation between individual crystals and variation among the ASIC channels. We also compare the same crystals with and without a grounded guard band deposited on the crystal side walls vs. a floating guard band and compare results to simulations. This study was carried out to find the optimum CZT crystal configuration for prototype detectors for the proposed Black-Hole Finder mission, EXIST.

  9. Charge transport optimization in CZT ring-drift detectors

    Science.gov (United States)

    Boothman, V.; Alruhaili, A.; Perumal, V.; Sellin, P.; Lohstroh, A.; Sawhney, K.; Kachanov, S.

    2015-12-01

    Ring-drift design has been applied to large (7.5~\\text{mm}× 7.5~\\text{mm}× 2.3 mm) cadmium zinc telluride (CZT) devices. This low-noise, single-carrier-sensing configuration is the gold standard for spectroscopic silicon x-ray detectors. By combining the advantages of ring-drift with the high quantum efficiency and room-temperature operating capabilities of CZT, a simple and compact device for high-resolution spectroscopy of x-rays in the range 50-500 keV can be created. Quality of CZT crystals has improved greatly in recent years and electron-only sensing overcomes the problem of inherently poor hole transport in II-VI semiconductors. The spatial response of our 3-ring CZT device was studied by microbeam scanning while the voltages applied to all electrodes were systematically varied. Maximum active radius extended to 2.3 mm, beyond the second ring. Resolution was limited by electronic noise. Our results show that the lateral field and its ratio to the bulk field exert a crucial influence on active area, peak position and sensitivity. CZT and the device geometry were modelled in 3D with Sentaurus TCAD. Line scans were simulated and trends in performance with bias conditions matched experimental data, validating the model. We aimed to optimize the resolution, sensitivity and active radius of the device. Fields and charge drift were visualized and the active volume was mapped in 3D to improve understanding of the factors governing performance including number of rings, their widths, positions and bias.

  10. Pixelated gamma detector

    Energy Technology Data Exchange (ETDEWEB)

    Dolinsky, Sergei Ivanovich; Yanoff, Brian David; Guida, Renato; Ivan, Adrian

    2016-12-27

    A pixelated gamma detector includes a scintillator column assembly having scintillator crystals and optical transparent elements alternating along a longitudinal axis, a collimator assembly having longitudinal walls separated by collimator septum, the collimator septum spaced apart to form collimator channels, the scintillator column assembly positioned adjacent to the collimator assembly so that the respective ones of the scintillator crystal are positioned adjacent to respective ones of the collimator channels, the respective ones of the optical transparent element are positioned adjacent to respective ones of the collimator septum, and a first photosensor and a second photosensor, the first and the second photosensor each connected to an opposing end of the scintillator column assembly. A system and a method for inspecting and/or detecting defects in an interior of an object are also disclosed.

  11. Hybrid Contacts for CZT Virtual Frisch-grid Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Camarda G.; Bolotnikov, A.E.; Chan, W.; Cui, Y.; Gul R.; Hossain, A.; Kim, K.; Yang, G.; James, R.B.

    2011-08-22

    In our previous design of virtual Frisch-grid CdZnTe (CZT) detectors, the charge drift-lines can be terminated at the side surfaces before the carriers reach the collecting anode; this results in a loss of signal from the interacting events near the detector's edges. Here, we describe our new design for the anode contact that reduces these edge effects by focusing the electric field towards the detectors' central axes. Four detectors were fabricated with the new hybrid anode contact, and their performances were evaluated and compared to those from the previous design for our virtual Frisch-grid detectors. The results obtained for all four showed similar improvement: therefore, we illustrate them with the findings from one detector.

  12. Recent advances in CZT strip detectors and coded mask imagers

    Science.gov (United States)

    Matteson, J. L.; Gruber, D. E.; Heindl, W. A.; Pelling, M. R.; Peterson, L. E.; Rothschild, R. E.; Skelton, R. T.; Hink, P. L.; Slavis, K. R.; Binns, W. R.; Tumer, T.; Visser, G.

    1999-09-01

    The UCSD, WU, UCR and Nova collaboration has made significant progress on the necessary techniques for coded mask imaging of gamma-ray bursts: position sensitive CZT detectors with good energy resolution, ASIC readout, coded mask imaging, and background properties at balloon altitudes. Results on coded mask imaging techniques appropriate for wide field imaging and localization of gamma-ray bursts are presented, including a shadowgram and deconvolved image taken with a prototype detector/ASIC and MURA mask. This research was supported by NASA Grants NAG5-5111, NAG5-5114, and NGT5-50170.

  13. ProtoEXIST: The Development of Advanced Tiled CZT Detector Planes for Wide Field Hard X-Ray Survey Telescope

    Science.gov (United States)

    Allen, Branden; Hong, J.; Grindlay, J.; Barthelmy, S.; Baker, R.

    2011-05-01

    ProtoEXIST is a technology development program for a coded aperture hard X-ray telescope with a large area (1-5 m^2) CZT detector plane for use in a future hard X-ray wide field sky monitor and survey telescope. The successful flight of the ProtoEXIST1 (P1) coded-aperture telescope concluded the first phase of the program on October 9, 2009. The black hole binary Cyg X-1 was imaged and its spectrum measured at the end of the (6h) flight. The P1 detector plane is comprised of a 8x8 array of detector crystal units (DCUs); each made up of a single 20 mm x 20 mm, 5 mm thick Redlen CZT crystal with a 8x8 pixilated anode (pixel pitch of 2.5 mm) bonded to an interposer board connecting each of the individual 64 anode pixels to a single input channel on a RadNET ASIC, forming a 256 cm^2 contiguous CZT imaging array with 4096 individual pixels. P1 was successfully recovered and has undergone further characterization in the interim. The program continues with the ongoing development ProtoEXIST2 (P2) utilizing a closely tiled 8x8 array of DCUs now with a reduced anode pixel pitch of 0.6 mm. Each DCU in P2 will consist of a CZT crystal, identical to that utilized in P1 now with a 32x32 pixelated anode, directly bonded to a single NuSTAR ASIC (Nu-ASIC). The fully assembled P2 imaging detector will be comprised of a semi-contiguous 256x256 array of pixels on 256 cm^2 of CZT. With its finer pixelation the P2 detector plane will enable 5' (FWHM) imaging with a 70 cm focal length and will be flown side-by-side with P1 from Ft. Sumner in the Spring of 2012. Results from the characterization of the P1 detector are discussed as well as current progress in the development of the P2 detector plane.

  14. Performance evaluation of a small CZT pixelated semiconductor gamma camera system with a newly designed stack-up parallel-hole collimator

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youngjin [Department of Radiological Science, College of Health Science, Eulji University, 553 Sanseong-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do 461-713 (Korea, Republic of); Kim, Hee-Joung, E-mail: hjk1@yonsei.ac.kr [Department of Radiological Science, College of Health Science, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 220-710 (Korea, Republic of)

    2015-09-11

    Gamma ray imaging techniques that use a cadmium zinc telluride (CZT) or cadmium telluride (CdTe) pixelated semiconductor detectors have rapidly gained popularity as a key tool for nuclear medicine research. By using a pinhole collimator with a pixelated semiconductor gamma camera system, better spatial resolution can be achieved. However, this improvement in spatial resolution is accomplished with a decrease in the sensitivity due to the small collimator hole diameter. Furthermore, few studies have been conducted for novel parallel-hole collimator geometric designs with pixelated semiconductor gamma camera systems. A gamma camera system which combines a CZT pixelated semiconductor detector with a newly designed stack-up parallel-hole collimator was developed and evaluated. The eValuator-2500 CZT pixelated semiconductor detector (eV product, Saxonburg, PA) was selected for the gamma camera system. This detector consisted of a row of four CZT crystals of 12.8 mm in length with 3 mm in thickness. The proposed parallel-hole collimator consists of two layers. The upper layer results in a fourfold increase in hole size compared to a matched square hole parallel-hole collimator with an equal hole and pixel size, while the lower layer also consisted of fourfold holes size and pretty acts as a matched square hole parallel-hole collimator. The overlap ratios of these collimators were 1:1, 1:2, 2:1, 1:5, and 5:1. These collimators were mounted on the eValuator-2500 CZT pixelated semiconductor detector. The basic performance of the imaging system was measured for a {sup 57}Co gamma source (122 keV). The measured averages of sensitivity and spatial resolution varied depending on the overlap ratios of the proposed parallel-hole collimator and source-to-collimator distances. One advantage of our system is the use of stacked collimators that can select the best combination of system sensitivity and spatial resolution. With low counts, we can select a high sensitivity collimator

  15. ProtoEXIST2: Advanced Wide-field Imaging CZT Detector Development For The HET On The Proposed EXIST Mission

    Science.gov (United States)

    Hong, JaeSub; Allen, B.; Grindlay, J.; Barthelmy, S.; Baker, R.; Gehrels, N.; Cook, W.; Kaye, S.; Harrison, F.

    2010-03-01

    We describe our development of ProtoEXIST2, the advanced CZT imaging detector and wide field telescope prototype for the High Energy Telescope (HET) on the proposed Energetic X-ray Imaging Survey Telescope (EXIST) mission. EXIST is a multi-wavelength Medium class mission which would explore the early Universe using high redshift Gamma-ray Bursts and survey black holes on all scales. ProtoEXIST2 will demonstrate the feasibility of a large scale imaging module (256 cm2) with a close-tiled array of fine pixel (0.6 mm) CZT with a balloon flight test in 2010 or 2011. This second generation close-tiled CZT imager follows ProtoEXIST1, which had a recent successful balloon flight (see Allen et al in this meeting) using the same area CZT detector module (256 cm2) but with larger pixel size (2.5mm). For signal readout and event processing, we use the Direct-Bond (DB) ASIC, developed for the NuSTAR mission to be used in a close-tiled 2 x 2 array of 2x2 cm2 CZT detectors, each with 32x32 pixels. The DB-ASIC is attractive for a large scale implementation of tiled imaging CZT detectors given its low noise and power consumption (70uW/pixel). We are developing readout for the DB-ASIC that incorporates our back-end FPGA readout architecture developed for ProtoEXIST1 in order to accomplish the 256 cm2 detector module area with totally vertical integration (i.e. no auxialliary boards to the sides of the module. This is required to tile large numbers of modules into the very large total area (4.5m^2) proposed for the HET on EXIST. We review the design of the EXIST/HET and its optimum shielding in light of our ProtoEXIST1 balloon flight and our plan for future development of ProtoEXIST3, a final EXIST/HET detector module that would incorporate a still lower power version of the DB ASIC.

  16. Characterization of CZT detectors for the ASIM mission

    DEFF Research Database (Denmark)

    Budtz-Jørgensen, Carl; Kuvvetli, Irfan; Skogseide, Y

    2008-01-01

    ) shall, situated on the International Space Station, detect Terrestrial Gamma ray Flashes (TGF) generated in the Earth atmosphere. TGFs are believed to be produced in connection with thunderstorms and ASIM will therefore also be equipped with optical instruments which trigger on lightening.......The National Space Institute, Technical University of Denmark is responsible for the selection and characterization of the CZT detector crystals for the X and gamma -ray instrument MXGS onboard ESA’s Atmospheric Space Interaction Monitor (ASIM) mission. The Modular X- and Gamma ray Sensor (MXGS...

  17. Charge collection and depth sensing investigation on CZT drift strip detectors

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Caroli, E.

    2010-01-01

    CZT drift strip detectors with Planar Transverse Field (PTF) configuration are suitable for high energy astrophysics instrumentation, where high efficiency, high energy and position resolution are required from the sensors. We report on experimental investigations on the DTU Space developed CZT...... drift detector operated in PTF configuration with the purpose of demonstrating that the good energy resolution of the CZT drift detector can be combined with the high efficiency of the PTF configuration. A CZT drift strip detector (10 mm x 10 mm x 2.5 mm) was characterized in PTF configuration....... With these measurements, we demonstrated to achieve high efficiency due to large effective thickness, high energy resolution due to small electron drift lengths and sub mm position resolution using depth information using CZT drift strip detectors with N+1 readout channels in PTF configuration....

  18. Characterization and selection of CZT detector modules for HEX experiment onboard Chandrayaan-1

    Energy Technology Data Exchange (ETDEWEB)

    Vadawale, S.V. [Physical Research Laboratory, Navarangpura, Ahmedabad 380 009 (India)], E-mail: santoshv@prl.res.in; Purohit, S.; Shanmugam, M.; Acharya, Y.B.; Goswami, J.N. [Physical Research Laboratory, Navarangpura, Ahmedabad 380 009 (India); Sudhakar, M.; Sreekumar, P. [Space Astronomy and Instrumentation Division, ISRO Satellite Center, Bangalore 560 017 (India)

    2009-01-11

    We present the results of characterization of a large sample of Cadmium Zinc Telluride (CZT) detector modules planned to be used for the HEX (High Energy X-ray spectrometer) experiment onboard India's first mission to the Moon, Chandrayaan-1. We procured forty modules from Orbotech Medical Solutions Ltd. and carried out a detailed characterization of each module at various temperatures and selected final nine detector modules for the flight model of HEX. Here we present the results of the characterization of all modules and the selection procedure for the HEX flight detector modules. These modules show 5-6% energy resolution (at 122 keV, for best 90% of pixels) at room temperature which is improved to {approx}4% when these modules are cooled to sub-0 deg. C temperature. The gain and energy resolution were stable during the long duration tests.

  19. Large dynamic range 64-channel ASIC for CZT or CdTe detectors

    Energy Technology Data Exchange (ETDEWEB)

    Glasser, F. E-mail: francis.glasser@cea.fr; Villard, P.; Rostaing, J.P.; Accensi, M.; Baffert, N.; Girard, J.L

    2003-08-21

    We present a customized 64-channel ASIC, named ALIX, developed in a 0.8 {mu}m CMOS technology. This circuit is dedicated to measure charges from semi-conductor X-ray detectors like Cadmium Zinc Telluride (CZT) or Cadmium Telluride CdTe. The specificity of ALIX is to be able to measure charges over a very large dynamic range (from 10 fC to 3 nC), and to store eight measurements in a very short time (from every 250 ns to a few ms). Up to eight images are stored inside the ASIC and each image can be read out in 64 {mu}s. A new acquisition sequence can then be started. Two analog readouts are available, one for the X-ray signal and one for the offset and afterglow measurement in case of pulsed X-rays. The outputs are converted into digital values by two off-chip 14 bits Analog-to-Digital Converters (ADC). A first version of ALIX has been tested with CZT and CdTe detectors under high-energy pulsed X-ray photons (20 MeV, 60 ns pulses every 250 ns). We will present the different results of linearity and signal-to-noise ratio. A second version of ALIX has been designed with some corrections. Electrical tests performed on 85 ASICS showed that the corrections were successful. We are now able to integrate them behind a 64x32 pixels 1 mm pitch CZT detector. Such an ASIC could also be used for strip detectors where a large dynamic range and a fast response are necessary.

  20. Large dynamic range 64-channel ASIC for CZT or CdTe detectors

    Science.gov (United States)

    Glasser, F.; Villard, P.; Rostaing, J. P.; Accensi, M.; Baffert, N.; Girard, J. L.

    2003-08-01

    We present a customized 64-channel ASIC, named ALIX, developed in a 0.8 μm CMOS technology. This circuit is dedicated to measure charges from semi-conductor X-ray detectors like Cadmium Zinc Telluride (CZT) or Cadmium Telluride CdTe. The specificity of ALIX is to be able to measure charges over a very large dynamic range (from 10 fC to 3 nC), and to store eight measurements in a very short time (from every 250 ns to a few ms). Up to eight images are stored inside the ASIC and each image can be read out in 64 μs. A new acquisition sequence can then be started. Two analog readouts are available, one for the X-ray signal and one for the offset and afterglow measurement in case of pulsed X-rays. The outputs are converted into digital values by two off-chip 14 bits Analog-to-Digital Converters (ADC). A first version of ALIX has been tested with CZT and CdTe detectors under high-energy pulsed X-ray photons (20 MeV, 60 ns pulses every 250 ns). We will present the different results of linearity and signal-to-noise ratio. A second version of ALIX has been designed with some corrections. Electrical tests performed on 85 ASICS showed that the corrections were successful. We are now able to integrate them behind a 64×32 pixels 1 mm pitch CZT detector. Such an ASIC could also be used for strip detectors where a large dynamic range and a fast response are necessary.

  1. Improving the spatial resolution in CZT detectors using charge sharing effect and transient signal analysis: Simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Xiaoqing; Cheng, Zeng [Department of Electrical and Computer Engineering, McMaster University (Canada); Deen, M. Jamal, E-mail: jamal@mcmaster.ca [Department of Electrical and Computer Engineering, McMaster University (Canada); School of Biomedical Engineering, McMaster University (Canada); Peng, Hao, E-mail: penghao@mcmaster.ca [Department of Electrical and Computer Engineering, McMaster University (Canada); School of Biomedical Engineering, McMaster University (Canada); Department of Medical Physics, McMaster University, Ontario L8S 4K1, Hamilton (Canada)

    2016-02-01

    Cadmium Zinc Telluride (CZT) semiconductor detectors are capable of providing superior energy resolution and three-dimensional position information of gamma ray interactions in a large variety of fields, including nuclear physics, gamma-ray imaging and nuclear medicine. Some dedicated Positron Emission Tomography (PET) systems, for example, for breast cancer detection, require higher contrast recovery and more accurate event location compared with a whole-body PET system. The spatial resolution is currently limited by electrode pitch in CZT detectors. A straightforward approach to increase the spatial resolution is by decreasing the detector electrode pitch, but this leads to higher fabrication cost and a larger number of readout channels. In addition, inter-electrode charge spreading can negate any improvement in spatial resolution. In this work, we studied the feasibility of achieving sub-pitch spatial resolution in CZT detectors using two methods: charge sharing effect and transient signal analysis. We noted that their valid ranges of usage were complementary. The dependences of their corresponding valid ranges on electrode design, depth-of-interaction (DOI), voltage bias and signal triggering threshold were investigated. The implementation of these two methods in both pixelated and cross-strip configuration of CZT detectors were discussed. Our results show that the valid range of charge sharing effect increases as a function of DOI, but decreases with increasing gap width and bias voltage. For a CZT detector of 5 mm thickness, 100 µm gap and biased at 400 V, the valid range of charge sharing effect was found to be about 112.3 µm around the gap center. This result complements the valid range of the transient signal analysis within one electrode pitch. For a signal-to-noise ratio (SNR) of ~17 and preliminary measurements, the sub-pitch spatial resolution is expected to be ~30 µm and ~250 µm for the charge sharing and transient signal analysis methods

  2. Improving the spatial resolution in CZT detectors using charge sharing effect and transient signal analysis: Simulation study

    Science.gov (United States)

    Zheng, Xiaoqing; Cheng, Zeng; Deen, M. Jamal; Peng, Hao

    2016-02-01

    Cadmium Zinc Telluride (CZT) semiconductor detectors are capable of providing superior energy resolution and three-dimensional position information of gamma ray interactions in a large variety of fields, including nuclear physics, gamma-ray imaging and nuclear medicine. Some dedicated Positron Emission Tomography (PET) systems, for example, for breast cancer detection, require higher contrast recovery and more accurate event location compared with a whole-body PET system. The spatial resolution is currently limited by electrode pitch in CZT detectors. A straightforward approach to increase the spatial resolution is by decreasing the detector electrode pitch, but this leads to higher fabrication cost and a larger number of readout channels. In addition, inter-electrode charge spreading can negate any improvement in spatial resolution. In this work, we studied the feasibility of achieving sub-pitch spatial resolution in CZT detectors using two methods: charge sharing effect and transient signal analysis. We noted that their valid ranges of usage were complementary. The dependences of their corresponding valid ranges on electrode design, depth-of-interaction (DOI), voltage bias and signal triggering threshold were investigated. The implementation of these two methods in both pixelated and cross-strip configuration of CZT detectors were discussed. Our results show that the valid range of charge sharing effect increases as a function of DOI, but decreases with increasing gap width and bias voltage. For a CZT detector of 5 mm thickness, 100 μm gap and biased at 400 V, the valid range of charge sharing effect was found to be about 112.3 μm around the gap center. This result complements the valid range of the transient signal analysis within one electrode pitch. For a signal-to-noise ratio (SNR) of ~17 and preliminary measurements, the sub-pitch spatial resolution is expected to be ~30 μm and ~250 μm for the charge sharing and transient signal analysis methods

  3. Performance evaluation of high-resolution square parallel-hole collimators with a CZT room temperature pixelated semiconductor SPECT system: a Monte Carlo simulation study

    Science.gov (United States)

    Lee, Y.; Kang, W.

    2015-07-01

    The pixelated semiconductor based on cadmium zinc telluride (CZT) is a promising imaging device that provides many benefits compared with conventional scintillation detectors. By using a high-resolution square parallel-hole collimator with a pixelated semiconductor detector, we were able to improve both sensitivity and spatial resolution. Here, we present a simulation of a CZT pixleated semiconductor single-photon emission computed tomography (SPECT) system with a high-resolution square parallel-hole collimator using various geometric designs of 0.5, 1.0, 1.5, and 2.0 mm X-axis hole size. We performed a simulation study of the eValuator-2500 (eV Microelectronics Inc., Saxonburg, PA, U.S.A.) CZT pixelated semiconductor detector using a Geant4 Application for Tomographic Emission (GATE). To evaluate the performances of these systems, the sensitivity and spatial resolution was evaluated. Moreover, to evaluate the overall performance of the imaging system, a hot-rod phantom was designed. Our results showed that the average sensitivity of the 2.0 mm collimator X-axis hole size was 1.34, 1.95, and 3.92 times higher than that of the 1.5, 1.0, and 0.5 mm collimator X-axis hole size, respectively. Also, the average spatial resolution of the 0.5 mm collimator X-axis hole size was 28.69, 44.65, and 55.73% better than that of the 1.0, 1.5, and 2.0 mm collimator X-axis hole size, respectively. We discuss the high-resolution square parallel-hole collimator of various collimator geometric designs and our evaluations. In conclusion, we have successfully designed a high-resolution square parallel-hole collimator with a CZT pixelated semiconductor SPECT system.

  4. A 3D CZT high resolution detector for x- and gamma-ray astronomy

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Zappettini, A.

    2014-01-01

    At DTU Space we have developed a high resolution three dimensional (3D) position sensitive CZT detector for high energy astronomy. The design of the 3D CZT detector is based on the CZT Drift Strip detector principle. The position determination perpendicular to the anode strips is performed using...... a novel interpolating technique based on the drift strip signals. The position determination in the detector depth direction, is made using the DOI technique based the detector cathode and anode signals. The position determination along the anode strips is made with the help of 10 cathode strips...... layer between the drift strip electrodes and CZT detector material. This method was applied to all the proto type detectors and was a very effective method to reduce the surface leakage current between the strips. The proto type detector was recently investigated at the European Synchrotron Radiation...

  5. Radiation damage measurements on CZT drift strip detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kuvvetli, I. E-mail: irfan@dsri.dk; Budtz-Joergensen, C. E-mail: carl@dsri.dk; Korsbech, U.; Jensen, H.J

    2003-10-11

    At DSRI, in collaboration with the cyclotron facility at Copenhagen University Hospital, we have performed a study of radiation effects exposing a 2.7 mm thick CZT drift strip detector to 30 MeV protons. The detector characteristics were evaluated after exposure to a number of fluences in the range from 2x10{sup 8} to 60x10{sup 8} p{sup +}/cm{sup 2}. Even for the highest fluences, which had a dramatic effect on the spectroscopic performance, we were able to recover the detectors after an appropriate annealing procedure. The radiation damage was studied as a function of depth inside the detector material. A numerical model that emulates the physical processes of the charge transport in the CZT detector was used to derive the charge trapping parameter, {mu}{tau}{sub e} (the product of charge mobility and trapping time) as a function of fluence. The analysis showed that the electron trapping increased proportionately with the proton dose. The radiation contribution to the electron trapping was found to obey the following relation: ({mu}{tau}{sub e}{sup -1}){sub rad}=(2.5{+-}0.2)x10{sup -7}xPHI (V/cm){sup 2} with the proton fluence, PHI in p{sup +}/cm{sup 2}. The trapping depth dependence, however, did not agree well with the damage profile calculated using the standard Monte Carlo simulations, TRIM , for the proton-induced radiation effects. The present results suggest that proton-induced nuclear reactions contribute significantly to the radiation damage. Further work will elaborate on these effects.

  6. Radiation damage measurements on CZT drift strip detectors

    Science.gov (United States)

    Kuvvetli, I.; Budtz-Jørgensen, C.; Korsbech, U.; Jensen, H. J.

    2003-10-01

    At DSRI, in collaboration with the cyclotron facility at Copenhagen University Hospital, we have performed a study of radiation effects exposing a 2.7 mm thick CZT drift strip detector to 30 MeV protons. The detector characteristics were evaluated after exposure to a number of fluences in the range from 2×10 8 to 60×10 8 p +/cm 2. Even for the highest fluences, which had a dramatic effect on the spectroscopic performance, we were able to recover the detectors after an appropriate annealing procedure. The radiation damage was studied as a function of depth inside the detector material. A numerical model that emulates the physical processes of the charge transport in the CZT detector was used to derive the charge trapping parameter, μτe (the product of charge mobility and trapping time) as a function of fluence. The analysis showed that the electron trapping increased proportionately with the proton dose. The radiation contribution to the electron trapping was found to obey the following relation: (μτ e- 1) rad=(2.5±0.2)×10 -7×Φ ( V/cm)2 with the proton fluence, Φ in p +/cm 2. The trapping depth dependence, however, did not agree well with the damage profile calculated using the standard Monte Carlo simulations, TRIM [1], for the proton-induced radiation effects. The present results suggest that proton-induced nuclear reactions contribute significantly to the radiation damage. Further work will elaborate on these effects.

  7. VNR CMS Pixel detector replacement

    CERN Document Server

    2017-01-01

    Joel Butler, spokesperson of the CMS collaboration explains how a team from many different partner institutes installed a new detector in CMS. This detector is the silicon pixel detector and they’ve been working on it for about five years, to replace one of our existing detectors. This detectors measures particles closer to the beam than any of the other components of this huge detector behind me. It gives us the most precise picture of tracks as they come out of the collisions and expand and travel through the detector. This particular device has twice as many pixels, 120 million, as opposed to about 68 million in the old detector and it can take data faster and pump it out to the analysis more quickly. 00’53’’ Images of the descent, insertion and installation of first piece of the Pixel detector on Tue Feb 28. Images of the descent, insertion and installation of second piece of the Pixel and the two cylinders being joined.

  8. CMS Barrel Pixel Detector Overview

    CERN Document Server

    Kästli, H C; Erdmann, W; Gabathuler, K; Hörmann, C; Horisberger, Roland Paul; König, S; Kotlinski, D; Meier, B; Robmann, P; Rohe, T; Streuli, S

    2007-01-01

    The pixel detector is the innermost tracking device of the CMS experiment at the LHC. It is built from two independent sub devices, the pixel barrel and the end disks. The barrel consists of three concentric layers around the beam pipe with mean radii of 4.4, 7.3 and 10.2 cm. There are two end disks on each side of the interaction point at 34.5 cm and 46.5 cm. This article gives an overview of the pixel barrel detector, its mechanical support structure, electronics components, services and its expected performance.

  9. Development of a low noise readout ASIC for CZT detectors for gamma-ray spectroscopy applications

    Science.gov (United States)

    Luo, J.; Deng, Z.; Wang, G.; Li, H.; Liu, Y.

    2012-08-01

    A multi-channel readout ASIC for pixelated CZT detectors has been developed for gamma-ray spectroscopy applications. Each channel consists of a low noise dual-stage charge sensitive amplifier (CSA), a CR-(RC)4 semi-Gaussian shaper and a class-AB output buffer. The equivalent noise charge (ENC) of input PMOS transistor is optimized for 5 pF input capacitance and 1 μs peaking time using gm/ID design methodology. The gain can be adjusted from 100 mV/fC to 400 mV/fC and the peaking time can be adjusted from 1 μs to 4 μs. A 16-channel chip has been designed and fabricated in 0.35 μm 2P4M CMOS technology. The test results show that the chip works well and fully satisfies the design specifications. The ENC was measured to be 72 e + 26 e/pF at 1 μs peaking time and 86 e + 20 e/pF at 4 μs peaking time. The non-uniformity of the channel gain and ENC was less than ±12% and ±11% respectively for 16 channels in one chip. The chip was also tested with a pixelated CZT detector at room temperature. The measured energy resolution at 59.5 keV photopeak of 241Am and 122 keV photopeak of 57Co were 4.5% FWHM and 2.8% FWHM for the central area pixels, respectively.

  10. Preliminary test results of a new high-energy-resolution silicon and CdZnTe pixel detectors for application to x-ray astronomy

    Science.gov (United States)

    Sushkov, V. V.; Hamilton, William J.; Hurley, Kevin; Maeding, Dale G.; Ogelman, Hakki; Paulos, Robert J.; Puetter, Richard C.; Tumer, Tumay O.; Zweerink, Jeffrey

    1999-10-01

    New, high spatial resolution CdZnTe (CZT) and silicon (Si) pixel detectors are highly suitable for x-ray astronomy. These detectors are planned for use in wide field of view, imaging x-ray, and low energy gamma-ray all-sky monitor (AXGAM) in a future space mission. The high stopping power of CZT detectors combined with low-noise front-end readout makes possible an order of magnitude improvement in spatial and energy resolution in x-ray detection. The AXGAM instrument will be built in the form of a fine coded aperture placed over two-dimensional, high spatial resolution and low energy threshold CZT pixel detector array. The preliminary result of CZT and silicon pixel detector test with low-noise readout electronics system are presented. These detectors may also be used with or without modification for medical and industrial imaging.

  11. Radiation damage measurements on CZT drift strip detectors

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Korsbech, Uffe C C

    2003-01-01

    At DSRI, in collaboration with the cyclotron facility at Copenhagen University Hospital, we have performed a study of radiation effects exposing a 2.7 mm thick CZT drift strip detector to 30 MeV protons. The detector characteristics were evaluated after exposure to a number of fluences in the range...... from 2 x 10(8) to 60 x 10(8) p(+)/cm(2). Even for the highest fluences, which had a dramatic effect on the spectroscopic performance, we were able to recover the detectors after an appropriate annealing procedure. The radiation damage was studied as a function of depth inside the detector material...... with the proton dose. The radiation contribution to the electron trapping was found to obey the following relation: (mutau(e)(-1))(rad) = (2.5+/-0.2) x 10(-7) x Phi (V/cm)(2) with the proton fluence, Phi in p(+)/cm(2). The trapping depth dependence, however, did not agree well with the damage profile calculated...

  12. The ALICE pixel detector

    CERN Document Server

    Mercado Perez, J

    2002-01-01

    The present document is a brief summary of the performed activities during the 2001 Summer Student Programme at CERN under the Scientific Summer at Foreign Laboratories Program organized by the Particles and Fields Division of the Mexican Physical Society (Sociedad Mexicana de Fisica). In this case, the activities were related with the ALICE Pixel Group of the EP-AIT Division, under the supervision of Jeroen van Hunen, research fellow in this group. First, I give an introduction and overview to the ALICE experiment; followed by a description of wafer probing. A brief summary of the test beam that we had from July 13th to July 25th is given as well. (3 refs).

  13. Evaluation of a photon counting Medipix3RX CZT spectral x-ray detector

    Science.gov (United States)

    Jorgensen, Steven M.; Vercnocke, Andrew J.; Rundle, David S.; Butler, Philip H.; McCollough, Cynthia H.; Ritman, Erik L.

    2016-10-01

    We assessed the performance of a cadmium zinc telluride (CZT)-based Medipix3RX x-ray detector as a candidate for micro-computed tomography (micro-CT) imaging. This technology was developed at CERN for the Large Hadron Collider. It features an array of 128 by 128, 110 micrometer square pixels, each with eight simultaneous threshold counters, five of which utilize real-time charge summing, significantly reducing the charge sharing between contiguous pixels. Pixel response curves were created by imaging a range of x-ray intensities by varying x-ray tube current and by varying the exposure time with fixed x-ray current. Photon energy-related assessments were made by flooding the detector with the tin foil filtered emission of an I-125 radioisotope brachytherapy seed and sweeping the energy threshold of each of the four charge-summed counters of each pixel in 1 keV steps. Long term stability assessments were made by repeating exposures over the course of one hour. The high properly-functioning pixel yield (99%), long term stability (linear regression of whole-chip response over one hour of acquisitions: y = -0.0038x + 2284; standard deviation: 3.7 counts) and energy resolution (2.5 keV FWHM (single pixel), 3.7 keV FWHM across the full image) make this device suitable for spectral micro-CT. The charge summing performance effectively reduced the measurement corruption caused by charge sharing which, when unaccounted for, shifts the photon energy assignment to lower energies, degrading both count and energy accuracy. Effective charge summing greatly improves the potential for calibrated, energy-specific material decomposition and K edge difference imaging approaches.

  14. Evaluation of a photon counting Medipix3RX CZT spectral x-ray detector

    Science.gov (United States)

    Jorgensen, Steven M.; Vercnocke, Andrew J.; Rundle, David S.; Butler, Philip H.; McCollough, Cynthia H.; Ritman, Erik L.

    2016-01-01

    We assessed the performance of a cadmium zinc telluride (CZT)-based Medipix3RX x-ray detector as a candidate for micro-computed tomography (micro-CT) imaging. This technology was developed at CERN for the Large Hadron Collider. It features an array of 128 by 128, 110 micrometer square pixels, each with eight simultaneous threshold counters, five of which utilize real-time charge summing, significantly reducing the charge sharing between contiguous pixels. Pixel response curves were created by imaging a range of x-ray intensities by varying x-ray tube current and by varying the exposure time with fixed x-ray current. Photon energy-related assessments were made by flooding the detector with the tin foil filtered emission of an I-125 radioisotope brachytherapy seed and sweeping the energy threshold of each of the four charge-summed counters of each pixel in 1 keV steps. Long term stability assessments were made by repeating exposures over the course of one hour. The high properly-functioning pixel yield (99%), long term stability (linear regression of whole-chip response over one hour of acquisitions: y = −0.0038x + 2284; standard deviation: 3.7 counts) and energy resolution (2.5 keV FWHM (single pixel), 3.7 keV FWHM across the full image) make this device suitable for spectral micro-CT. The charge summing performance effectively reduced the measurement corruption caused by charge sharing which, when unaccounted for, shifts the photon energy assignment to lower energies, degrading both count and energy accuracy. Effective charge summing greatly improves the potential for calibrated, energy-specific material decomposition and K edge difference imaging approaches.

  15. Signal modeling of charge sharing effect in simple pixelated CdZnTe detector

    Science.gov (United States)

    Kim, Jae Cheon; Kaye, William R.; He, Zhong

    2014-05-01

    In order to study the energy resolution degradation in 3D position-sensitive pixelated CdZnTe (CZT) detectors, a detailed detector system modeling package has been developed and used to analyze the detector performance. A 20 × 20 × 15 mm3 CZT crystal with an 11 × 11 simple-pixel anode array and a 1.72 mm pixel pitch was modeled. The VAS UM/TAT4 Application Specific Integrated Circuitry (ASIC) was used for signal read-out. Components of the simulation package include gamma-ray interactions with the CZT crystal, charge induction, electronic noise, pulse shaping, and ASIC triggering procedures. The charge induction model considers charge drift, trapping, diffusion, and sharing between pixels. This system model is used to determine the effects of electron cloud sharing, weighting potential non-uniformity, and weighting potential cross-talk which produce non-uniform signal responses for different gamma-ray interaction positions and ultimately degrade energy resolution. The effect of the decreased weighting potential underneath the gap between pixels on the total pulse amplitude of events has been studied. The transient signals induced by electron clouds collected near the gap between pixels may generate false signals, and the measured amplitude can be even greater than the photopeak. As the number of pixels that collect charge increases, the probability of side-neighbor events due to charge sharing significantly increases. If side-neighbor events are not corrected appropriately, the energy resolution of pixelated CZT detectors in multiple-pixel events degrades rapidly.

  16. Signal modeling of charge sharing effect in simple pixelated CdZnTe detector

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae C.; Kaye, William R.; He, Zhong [University of Michigan, Ann Arbor, MI (United States)

    2014-05-15

    In order to study the energy resolution degradation in 3D position-sensitive pixelated CdZnTe (CZT) detectors, a detailed detector system modeling package has been developed and used to analyze the detector performance. A 20 x 20 x 15 mm{sup 3} CZT crystal with an 11 x 11 simple-pixel anode array and a 1.72 mm pixel pitch was modeled. The VAS UM/TAT4 Application Specific Integrated Circuitry (ASIC) was used for signal read-out. Components of the simulation package include gamma-ray interactions with the CZT crystal, charge induction, electronic noise, pulse shaping, and ASIC triggering procedures. The charge induction model considers charge drift, trapping, diffusion, and sharing between pixels. This system model is used to determine the effects of electron cloud sharing, weighting potential non-uniformity, and weighting potential cross-talk which produce non-uniform signal responses for different gamma-ray interaction positions and ultimately degrade energy resolution. The effect of the decreased weighting potential underneath the gap between pixels on the total pulse amplitude of events has been studied. The transient signals induced by electron clouds collected near the gap between pixels may generate false signals, and the measured amplitude can be even greater than the photopeak. As the number of pixels that collect charge increases, the probability of side-neighbor events due to charge sharing significantly increases. If side-neighbor events are not corrected appropriately, the energy resolution of pixelated CZT detectors in multiple-pixel events degrades rapidly.

  17. Charge sharing in common-grid pixelated CdZnTe detectors

    Science.gov (United States)

    Kim, Jae Cheon; Anderson, Stephen E.; Kaye, Willy; Zhang, Feng; Zhu, Yuefeng; Kaye, Sonal Joshi; He, Zhong

    2011-10-01

    The charge sharing effect in pixelated CdZnTe (CZT) detectors with a common anode steering grid has been studied. The impact on energy resolution of weighting potential cross-talk and ballistic deficit due to cathode signal shaping has been investigated. A detailed system modeling package considering charge induction, electronic noise, pulse shaping, and ASIC triggering procedures has been developed to study the characteristics of common-grid CZT detectors coupled to the VAS_UM/TAT4 ASIC. Besides an actual common-grid CZT detector coupled to VAS_UM/TAT4 ASIC, a prototype digital read-out system has been developed to better understand the nature of the charge sharing effect.

  18. Charge sharing in common-grid pixelated CdZnTe detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Cheon, E-mail: jaecheon@umich.edu [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Anderson, Stephen E.; Kaye, Willy; Zhang Feng; Zhu Yuefeng; Kaye, Sonal Joshi; He Zhong [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States)

    2011-10-21

    The charge sharing effect in pixelated CdZnTe (CZT) detectors with a common anode steering grid has been studied. The impact on energy resolution of weighting potential cross-talk and ballistic deficit due to cathode signal shaping has been investigated. A detailed system modeling package considering charge induction, electronic noise, pulse shaping, and ASIC triggering procedures has been developed to study the characteristics of common-grid CZT detectors coupled to the VAS{sub U}M/TAT4 ASIC. Besides an actual common-grid CZT detector coupled to VAS{sub U}M/TAT4 ASIC, a prototype digital read-out system has been developed to better understand the nature of the charge sharing effect.

  19. Status of the ATLAS pixel detector

    CERN Document Server

    Saavedra Aldo, F

    2005-01-01

    The ATLAS pixel detector is currently being constructed and will be installed in 2006 to be ready for commissioning at the Large Hadron Collider. The complete pixel detector is composed of three concentric barrels and six disks that are populated by 1744 ATLAS Pixel modules. The main components of the pixel module are the readout electronics and the silicon sensor whose active region is instrumented with rectangular pixels. The module has been designed to be able to survive 10 years of operation within the ATLAS detector. A brief description of the pixel detector will be presented with results and problems encountered during the production stage.

  20. Development of Tiled Imaging CZT Detectors for Sensitive Wide-Field Hard X-Ray Surveys to EXIST

    Science.gov (United States)

    Grindlay, J.; Hong, J.; Allen, B.; Barthelmy, S.; Baker, R.

    2011-01-01

    Motivated by the proposed EXIST mission, a "medium-class" space observatory to survey black holes and the Early Universe proposed to the 2010 NAS/NRC Astronomy and Astrophysics Decadal Survey, we have developed the first "large" area 256 sq cm close-tiled (0.6 mm gaps) hard X-ray (20-600 keV) imaging detector employing pixelated (2.5 mm) CdZnTe (CZT) detectors, each 2 x 2 x 0.5 cubic cm. We summarize the design, development and operation of this detector array (8 x 8 CZTs) and its performance as the imager for a coded aperture telescope on a high altitude (40 km) balloon flight in October. 2009, as the ProtoEX1STl payload. We then outline our current development of a second-generation imager, ProtcEXIST2. with 0.6 mm pixels on a 32 x 32 array on each CZT, and how it will lead to the ultimate imaging system needed for EXIST. Other applications of this technology will also be mentioned.

  1. The ALICE pixel detector upgrade

    Science.gov (United States)

    Reidt, F.

    2016-12-01

    The ALICE experiment at the CERN LHC is designed to study the physics of strongly interacting matter, and in particular the properties of the Quark-Gluon Plasma, using proton-proton, proton-nucleus and nucleus-nucleus collisions. The ALICE collaboration is preparing a major upgrade of the experimental apparatus to be installed during the second long LHC shutdown in the years 2019-2020. A key element of the ALICE upgrade is the new, ultra-light, high-resolution Inner Tracking System. With respect to the current detector, the new Inner Tracking System will significantly enhance the pointing resolution, the tracking efficiency at low transverse momenta, and the read-out rate capabilities. This will be obtained by seven concentric detector layers based on a Monolithic Active Pixel Sensor with a pixel pitch of about 30×30 μm2. A key feature of the new Inner Tracking System, which is optimised for high tracking accuracy at low transverse momenta, is the very low mass of the three innermost layers, which feature a material budget of 0.3% X0 per layer. This contribution presents the design goals and layout of the upgraded ALICE Inner Tracking System, summarises the R&D activities focussing on the technical implementation of the main detector components, and the projected detector performance.

  2. Measuring the mutual effects between a CZT detector and MRI for the development of a simultaneous MBI/MRI insert

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Ashley [McMaster University (Canada); Farncombe, Troy [Hamilton Health Sciences (Canada); Noseworthy, Michael [McMaster University (Canada)

    2015-05-18

    While mammography is the gold standard for breast cancer screening, it suffers from poor sensitivity in women with dense breast tissue. Both breast MRI and molecular breast imaging (MBI) have been used as secondary imaging techniques. However, breast MRI suffers from low specificity and low sensitivity in MBI. A CZT based detector system has been developed with the goal of simultaneous MBI/MRI imaging to address the shortcomings of each modality. The performance of each modality needs to be addressed separately and together. The CZT system is comprised of four Redlen CZT modules tiled in a 2x2 array. Each module consists of 256 pixels and feature a builtin on-board ASIC and FPGA. A custom digital readout circuit board was designed to interface the four modules with a microcontroller to a PC. MR images were acquired with a 3T GE Discovery MR750 and Hologic breast coils. A gradient echo imaging sequence was used for all image acquisitions. A tissue mimicking phantom with a plastic grid insert (1 cm spacing) was used to evaluate geometric accuracy with the CZT detectors in the MRI bore. The average distance between the grid markers was 1Å 0.2cm indicating negligible geometric distortion. Field maps were generated with a uniform phantom to quantify the effect on magnetic field homogeneity. Early results indicate a significant distortion (~10ppm) in the magnetic field closest to the coil. Further analysis of the MR images will determine the extent of image quality degradation. A flood map of Tc-99m was acquired to evaluate and implement an energy correction map and a uniformity map. In the absence of a magnetic field, the mean energy resolution at 140keV was 6.3%. After fully characterizing the uniformity, geometric accuracy and sensitivity, the same metrics will be evaluated in the MRI bore.

  3. Flight Performance of an advanced CZT Imaging Detector in a Balloon-borne Wide-Field Hard X-ray Telescope - ProtoEXIST1

    CERN Document Server

    Hong, J; Grindlay, J; Barthelemy, S; Baker, R; Garson, A; Krawczynski, H; Apple, J; Cleveland, W H

    2011-01-01

    We successfully carried out the first high-altitude balloon flight of a wide-field hard X-ray coded-aperture telescope ProtoEXIST1, which was launched from the Columbia Scientific Balloon Facility at Ft. Sumner, New Mexico on October 9, 2009. ProtoEXIST1 is the first implementation of an advanced CdZnTe (CZT) imaging detector in our ongoing program to establish the technology required for next generation wide-field hard X-ray telescopes. The CZT detector plane in ProtoEXIST1 consists of an 8 x 8 array of closely tiled 2 cm x 2 cm x 0.5 cm thick pixellated CZT crystals, each with 8 x 8 pixels, covering a 256 cm^2 active area with 2.5 mm pixels. A tungsten mask, mounted at 90 cm above the detector provides shadowgrams of X-ray sources in the 30 - 600 keV band for imaging, allowing a fully coded field of view of 9 Deg x 9 Deg with an angular resolution of 20 arcmin. To reduce the background radiation, the detector is surrounded by semi-graded (Pb/Sn/Cu) passive shields on the four sides all the way to the mask. ...

  4. Response of CZT drift-strip detector to X- and gamma rays

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl; Gerward, Leif

    2001-01-01

    The drift-strip method for improving the energy response of a CdZnTe (CZT) detector to hard X- and gamma rays is discussed. Results for a 10 x 10 x 3 mm(3) detector crystal demonstrate a remarkable improvement of the energy resolution. The full width at half maximum (FWHM) is 2.18 keV (3.6%), 2...

  5. Development of a CZT drift ring detector for X and γ ray spectroscopy

    Science.gov (United States)

    Alruhaili, A.; Sellin, P. J.; Lohstroh, A.; Boothman, V.; Veeramani, P.; Veale, M. C.; Sawhney, K. J. S.; Kachkanov, V.

    2015-04-01

    CdTe and CZT detectors are considered better choices for high energy γ and X-ray spectroscopy in comparison to Si and HPGe detectors due to their good quantum efficiency and room temperature operation. The performance limitations in CdTe and CZT detectors are mainly associated with poor hole transport and trapping phenomena. Among many techniques that can be used to eliminate the effect of the poor charge transport properties of holes in CdTe and CZT material, the drift ring technique shows promising results. In this work, the performance of a 2.3 mm thick CZT drift ring detector is investigated. Spatially resolved measurements were carried out with an X-ray microbeam (25 and 75 keV) at the Diamond Light Source synchrotron to study the response uniformity and extent of the active area. Higher energy photon irradiation was also carried out at up to 662 keV using different radioisotopes to complement the microbeam data. Different biasing schemes were investigated in terms of biasing the cathode rear electrode (bulk field) and the ring electrodes (lateral fields). The results show that increasing the bulk field with fixed-ratio ring biases and lateral fields with fixed bulk fields increase the active area of the device significantly, which contrasts with previous studies in CdTe, where only an increasing lateral field resulted in an improvement of device performance. This difference is attributed to the larger thickness of the CZT device reported here.

  6. Material properties limiting the performance of CZT gamma-ray detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov,A.E.; Babalola, S.; Camarda, G. S.; Cui, Y.; Egarievwe, S. U.; Hossain, A.; Yang, G.; James, R. B.

    2009-03-16

    CdZnTe (CZT) nuclear radiation detectors are advanced sensors that utilize innovative technologies developed for wide band-gap semiconductor industry and microelectronics. They open opportunities for new types of room-temperature operating, field deployable instruments that provide accurate identification of potential radiological threats and timely awareness for both the civilian and military communities. Room-temperature radiation detectors are an emerging technology that relies on the use of high-quality CZT crystals whose availability is currently limited by material non-uniformities and the presence of extended defects. To address these issues, which are most critical to CZT sensor developments, we developed X-ray mapping and IR transmission microscopy systems to characterize both CZT crystals and devices. Since a customized system is required for such X-ray measurements, we use synchrotron radiation beams available at BNL's National Synchrotron Light Source. A highly-collimated and high-intensity X-ray beam supports measurements of areas as small as 10 x 10 {micro}m{sup 2}, and allowed us to see fluctuations in collected charge over the entire area of the detector in a reasonable time. The IR microscopy system allows for 3D visualization of Te inclusions and other extended defects. In this paper, we describe the experimental techniques used in our measurements and typical results obtained from CZT samples produced by different suppliers.

  7. Development of the ProtoEXIST2 advanced CZT detector plane

    OpenAIRE

    Allen, Branden; Hong, JaeSub; Grindlay, Jonathan; Burke, Michael; Barthelmy, Scott; Baker, Robert; Harrison, Fiona; Mao, Peter; Cook, William

    2011-01-01

    The ProtoEXIST program was conceived for the development of a highly scalable detector plane architecture utilizing pixilated CdZnTe (CZT) detectors for eventual deployment in a large scale (1-4 m2 active area) coded aperture X-ray telescope. Development is now underway for ProtoEXIST2, which ultimately will be comprised of a closely tiled 8×8 array of 19.9 mm × 19.9 mm, 5 mm thick Redlen CZT crystals, analogous to ProtoEXIST1, but will now utilize the NuASIC which accommodates the direct bon...

  8. Development of a 3D CZT detector prototype for Laue Lens telescope

    Science.gov (United States)

    Caroli, Ezio; Auricchio, Natalia; Del Sordo, Stefano; Abbene, Leonardo; Budtz-Jørgensen, Carl; Casini, Fabio; Curado da Silva, Rui M.; Kuvvetlli, Irfan; Milano, Luciano; Natalucci, Lorenzo; Quadrini, Egidio M.; Stephen, John B.; Ubertini, Pietro; Zanichelli, Massimiliano; Zappettini, Andrea

    2010-07-01

    We report on the development of a 3D position sensitive prototype suitable as focal plane detector for Laue lens telescope. The basic sensitive unit is a drift strip detector based on a CZT crystal, (~19×8 mm2 area, 2.4 mm thick), irradiated transversally to the electric field direction. The anode side is segmented in 64 strips, that divide the crystal in 8 independent sensor (pixel), each composed by one collecting strip and 7 (one in common) adjacent drift strips. The drift strips are biased by a voltage divider, whereas the anode strips are held at ground. Furthermore, the cathode is divided in 4 horizontal strips for the reconstruction of the third interaction position coordinate. The 3D prototype will be made by packing 8 linear modules, each composed by one basic sensitive unit, bonded on a ceramic layer. The linear modules readout is provided by a custom front end electronics implementing a set of three RENA-3 for a total of 128 channels. The front-end electronics and the operating logics (in particular coincidence logics for polarisation measurements) are handled by a versatile and modular multi-parametric back end electronics developed using FPGA technology.

  9. CZT strip detectors for imaging and spectroscopy: Collimated beam and ASIC readout experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kurczynski, P. [Univ. of Maryland, College Park, MD (United States); Krizmanic, J.F.; Parsons, A. [Goddard Space Flight Center, Greenbelt, MD (United States)

    1996-12-31

    We report the status of ongoing investigations into Cadmium Zinc Telluride (CZT) strip detectors for application in hard x-ray astronomy. We have instrumented a nine strip by nine strip region of a two sided strip detector made in our detector fabrication facility. In order to measure the position resolution of our detectors, we have implemented a collimated beam that concentrates radiation to a spot size less than the strip width of our detector. We have also performed charge collection studies as a function of incident photon energy and bias voltage with a single sided, 100{mu}m pitch CZT strip detector wire bonded to an SVX ASIC charge amplifier. The detectors exhibited excellent strip uniformity in terms of photon count rate and spectroscopic information.

  10. Coded Mask Imaging of High Energy X-rays with CZT Detectors

    Science.gov (United States)

    Matteson, J. L.; Dowkontt, P. F.; Duttweiler, F.; Heindl, W. A.; Hink, P. L.; Huszar, G. L.; Kalemci, E.; Leblanc, P. C.; Rothschild, R. E.; Skelton, R. T.; Slavis, K. R.; Stephan, E. A.

    1998-12-01

    Coded mask imagers are appropriate for important objectives of high energy X-ray astronomy, e.g., gamma- ray burst localization, all-sky monitors and surveys, and deep surveys of limited regions. We report results from a coded mask imager developed to establish the proof-of-concept for this technique with CZT detectors. The detector is 2 mm thick with orthogonal crossed strip readout and an advanced electrode design to improve the energy resolution. Each detector face has 22 strip electrodes, and the strip pitch and pixel size are 500 microns. ASIC readout is used and the energy resolution varies from 3 to 6 keV FWHM over the 14 to 184 keV keV range. A coded mask with 2 x 2 cycles of a 23 x 23 MURA pattern (860 micron unit cell) was built from 600 micron thick tantalum to provide good X-ray modulation up to 200 keV. The detector, mask, and a tiny Gd-153 source of 41 keV X-rays were positioned with a spacing that caused the mask cells in the shadowgram to have a projected size of 1300 microns at the detector. Multiple detector positions were used to measure the shadowgram of a full mask cycle and this was recorded with 100 percent modulation transfer by the detector, due to its factor of 2.6 oversampling of the mask unit cell, and very high strip-to-strip selectivity and spatial accuracy. Deconvolution of the shadowgram produced a correlation image in which the source was detected as a 76-sigma peak with the correct FWHM and base diameter. Off-source image pixels had gaussian fluctuations that agree closely with the measurement statistics. Off-source image defects such as might be produced by systematic effects were too small to be seen and limited to <0.5 percent of the source peak. These results were obtained with the "raw" shadowgram and image; no "flat fielding" corrections were used.

  11. SemiSPECT: a small-animal single-photon emission computed tomography (SPECT) imager based on eight cadmium zinc telluride (CZT) detector arrays.

    Science.gov (United States)

    Kim, Hyunki; Furenlid, Lars R; Crawford, Michael J; Wilson, Donald W; Barber, H Bradford; Peterson, Todd E; Hunter, William C J; Liu, Zhonglin; Woolfenden, James M; Barrett, Harrison H

    2006-02-01

    The first full single-photon emission computed tomography (SPECT) imager to exploit eight compact high-intrinsic-resolution cadmium zinc telluride (CZT) detectors, called SemiSPECT, has been completed. Each detector consists of a CZT crystal and a customized application-specific integrated circuit (ASIC). The CZT crystal is a 2.7 cm x 2.7 cm x -0.2 cm slab with a continuous top electrode and a bottom electrode patterned into a 64 x 64 pixel array by photolithography. The ASIC is attached to the bottom of the CZT crystal by indium-bump bonding. A bias voltage of -180 V is applied to the continuous electrode. The eight detectors are arranged in an octagonal lead-shielded ring. Each pinhole in the eight-pinhole aperture placed at the center of the ring is matched to each individual detector array. An object is imaged onto each detector through a pinhole, and each detector is operated independently with list-mode acquisition. The imaging subject can be rotated about a vertical axis to obtain additional angular projections. The performance of SemiSPECT was characterized using 99mTc. When a 0.5 mm diameter pinhole is used, the spatial resolution on each axis is about 1.4 mm as estimated by the Fourier crosstalk matrix, which provides an algorithm-independent average resolution over the field of view. The energy resolution achieved by summing neighboring pixel signals in a 3 x 3 window is about 10% full-width-at-half-maximum of the photopeak. The overall system sensitivity is about 0.5 x 10(-4) with the energy window of +/-10% from the photopeak. Line-phantom images are presented to visualize the spatial resolution provided by SemiSPECT, and images of bone, myocardium, and human tumor xenografts in mice demonstrate the feasibility of preclinical small-animal studies with SemiSPECT.

  12. CVD diamond pixel detectors for LHC experiments

    Energy Technology Data Exchange (ETDEWEB)

    Wedenig, R.; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knoepfle, K.T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L.S.; Palmieri, V.G.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Procario, M.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Runolfsson, O.; Russ, J.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W.; Vittone, E.; Wagner, A.; Walsh, A.M.; Weilhammer, P.; White, C.; Zeuner, W.; Ziock, H.; Zoeller, M.; Blanquart, L.; Breugnion, P.; Charles, E.; Ciocio, A.; Clemens, J.C.; Dao, K.; Einsweiler, K.; Fasching, D.; Fischer, P.; Joshi, A.; Keil, M.; Klasen, V.; Kleinfelder, S.; Laugier, D.; Meuser, S.; Milgrome, O.; Mouthuy, T.; Richardson, J.; Sinervo, P.; Treis, J.; Wermes, N

    1999-08-01

    This paper reviews the development of CVD diamond pixel detectors. The preparation of the diamond pixel sensors for bump-bonding to the pixel readout electronics for the LHC and the results from beam tests carried out at CERN are described.

  13. Operational Experience with the ATLAS Pixel Detector

    CERN Document Server

    Lantzsch, Kerstin; The ATLAS collaboration

    2016-01-01

    Run 2 of the LHC is providing new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). In addition the Pixel detector was refurbished with new service quarter panels to recover about 3% of defective modules lost during run 1 and a new optical readout system to readout the data at higher speed while reducing the occupancy when running with increased luminosity. The commissioning, operation and performance of the 4-layer Pixel Detector will be presented.

  14. Defects in CZT crystals and their relationship to gamma-ray detector performance

    CERN Document Server

    Bürger, A; Chen, H; Ma, X; Ndap, J O; Schieber, M; Schlesinger, T E; Yao, H W; Erickson, J; James, R B

    2000-01-01

    This paper reviews some of the progress obtained in the understanding of defects in detector grade cadmium zinc telluride material (CZT). Several techniques have been utilized to elucidate some of the issues related to compositional uniformity, effects of precipitates, grain boundaries, and surface defects related to mechanical and chemical treatments. In few cases, special mapping capabilities had to be developed to allow correlations with detector performance.

  15. Interconnect and bonding techniques for pixelated X-ray and gamma-ray detectors

    Science.gov (United States)

    Schneider, A.; Veale, M. C.; Duarte, D. D.; Bell, S. J.; Wilson, M. D.; Lipp, J. D.; Seller, P.

    2015-02-01

    In the last decade, the Detector Development Group at the Technology Department of the Science and Technology Facilities Council (STFC), U.K., established a variety of fabrication and bonding techniques to build pixelated X-ray and γ-ray detector systems such as the spectroscopic X-ray imaging detector HEXITEC [1]. The fabrication and bonding of such devices comprises a range of processes including material surface preparation, photolithography, stencil printing, flip-chip and wire bonding of detectors to application-specific integrated circuits (ASIC). This paper presents interconnect and bonding techniques used in the fabrication chain for pixelated detectors assembled at STFC. For this purpose, detector dies (~ 20× 20 mm2) of high quality, single crystal semiconductors, such as cadmium zinc telluride (CZT) are cut to the required thickness (up to 5mm). The die surfaces are lapped and polished to a mirror-finish and then individually processed by electroless gold deposition combined with photolithography to form 74× 74 arrays of 200 μ m × 200 μ m pixels with 250 μ m pitch. Owing to a lack of availability of CZT wafers, lithography is commonly carried out on individual detector dies which represents a significant technical challenge as the edge of the pixel array and the surrounding guard band lies close to the physical edge of the crystal. Further, such detector dies are flip-chip bonded to readout ASIC using low-temperature curing silver-loaded epoxy so that the stress between the bonded detector die and the ASIC is minimized. In addition, this reduces crystalline modifications of the detector die that occur at temperature greater than 150\\r{ }C and have adverse effects on the detector performance. To allow smaller pitch detectors to be bonded, STFC has also developed a compression cold-weld indium bump bonding technique utilising bumps formed by a photolithographic lift-off technique.

  16. Upgrades of the ATLAS Pixel Detector

    CERN Document Server

    Hügging, F; The ATLAS collaboration

    2013-01-01

    The upgrade for the ATLAS detector will undergo different phases towards HL-LHC. The first upgrade for the Pixel Detector (Phase 1) consists in the construction of a new pixel layer, which will be installed during the 1st long shutdown of the LHC machine (LS1) in 2013/14. The new detector, called Insertable B-Layer (IBL), will be inserted between the existing pixel detector and a new (smaller radius) beam-pipe at a radius of about 3.2 cm. The IBL requires the development of several new technologies to cope with the increase of radiation and pixel occupancy as well as to improve the physics performance of the existing pixel detector. The pixel size is reduced and the material budget is minimized by using new lightweight mechanical support materials and a CO2 based cooling system. For Phase 2 upgrade of LHC a complete new 4-layer pixel system is planned as part of a new all silicon Inner Detector. The increase in luminosity to about $5\\cdot 10^{34}$cm$^{-2}$s$^{-1}$ together with a total expected lifetime of ab...

  17. Te Inclusions in CZT Detectors: New Method for Correcting Their Adverse Effects

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov, A.E.; Babalola, S.; Camarda, G.S.; Cui, Y.; Egarievwe, S.U.; Hawrami, R.; Hossain, A.; Yang, G.; James, R.B.

    2009-10-25

    Both Te inclusions and point defects can trap the charge carriers generated by ionizing particles in CdZnTe (CZT) detectors. The amount of charge trapped by point defects is proportional to the carriers’ drift time and can be corrected electronically. In the case of Te inclusions, the charge loss depends upon their random locations with respect to the electron cloud. Consequently, inclusions introduce fluctuations in the charge signals, which cannot be easily corrected. In this paper, we describe direct measurements of the cumulative effect of Te inclusions and its influence on the response of CZT detectors of different thicknesses and different sizes and concentrations of Te inclusions. We also discuss a means of partially correcting their adverse effects.

  18. Physics performance of the ATLAS pixel detector

    Science.gov (United States)

    Tsuno, S.

    2017-01-01

    In preparation for LHC Run-2 the ATLAS detector introduced a new pixel detector, the Insertable B-Layer (IBL). This detector is located between the beampipe and what was the innermost pixel layer. The tracking and vertex reconstruction are significantly improved and good performance is expected in high level objects such a b-quark jet tagging. This in turn, leads to better physics results. This note summarizes the impact of the IBL detector on physics results, especially focusing on the analyses using b-quark jets throughout 2016 summer physics program.

  19. Development of SOI pixel detector in Cracow

    CERN Document Server

    Bugiel, Szymon; Glab, Sebastian; Idzik, Marek; Moron, Jakub; Kapusta, Piotr Julian; Kucewicz, Wojciech; Turala, Michal

    2015-01-01

    This paper presents the design of a new monolithic Silicon-On-Insulator pixel sensor in $200~nm$ SOI CMOS technology. The main application of the proposed pixel detector is the spectroscopy, but it can also be used for the minimum ionizing particle (MIP) tracking in particle physics experiments. For this reason few different versions of pixel cells are developed: a source-follower based pixel for tracking, a low noise pixel with preamplifier for spectroscopy, and a self-triggering pixel for time and amplitude measurements. In addition the design of a Successive Approximation Register Analog-to-Digital Converter (SAR ADC) is also presented. A 10-bit SAR ADC is developed for spectroscopic measurements and a lower resolution 6-bit SAR ADC is integrated in the pixel matrix as a column ADC, for tracking applications.

  20. Synchrotron study of charge transport in a CZT ring-drift detector

    Energy Technology Data Exchange (ETDEWEB)

    Hartog, Roland den, E-mail: r.h.den.hartog@sron.nl [High-Energy Astrophysics division of SRON, The Netherlands Institute of Space Research, Sorbonnelaan 2, 3584 CA, Utrecht (Netherlands); Owens, A., E-mail: aowens@rssd.esa.int [Science Projects Department of the European Space Agency, at ESTEC, P.O. Box 299, 2200 AG, Noordwijk (Netherlands); Kozorezov, A.G., E-mail: a.kozorezov@lancaster.ac.uk [Department of Physics of the University of Lancaster (United Kingdom); Wigmore, J.K. [Department of Physics of the University of Lancaster (United Kingdom); Gostilo, V., E-mail: office@bruker-baltic.lv [Bruker Baltic SAI, Ganibudambis 26, P.O. Box 33, Riga, LV-1005 (Latvia); Webb, M.A. [Hamburger Synchrotronstrahlungslabor HASYLAB at the Deutsches Elektronen-Synchrotron DESY, Notke-Strasse 85, D-22603, Hamburg (Germany)

    2011-08-21

    We report on experimental and theoretical results obtained with a CdZnTe (CZT) detector with a versatile read-out scheme: the ring detector. This detector has been tested extensively both in our laboratories and at the HASYLAB synchrotron facility and has demonstrated excellent energy resolution of up to 0.73%, over a wide dynamic range covering 6-662 keV. The key feature in this design is carefully managed charge transport, which eliminates the hole contribution, and optimizes the electron collection. We have developed a theoretical model of this detector, to enable the optimization of the read-out structure as a function of detector dimensions. A comparison between X-ray scans across the detector and model calculations shows that the model already captures all the major detector features, but still leaves a few challenging questions related to CZT surface conductivity. A defect in the detector, which breaks the expected cylindrical symmetry of the charge transport, is examined in detail by differential spectrometry, a powerful technique, which exploits differences in X-ray absorption between bulk and defect.

  1. LISe pixel detector for neutron imaging

    Science.gov (United States)

    Herrera, Elan; Hamm, Daniel; Wiggins, Brenden; Milburn, Rob; Burger, Arnold; Bilheux, Hassina; Santodonato, Louis; Chvala, Ondrej; Stowe, Ashley; Lukosi, Eric

    2016-10-01

    Semiconducting lithium indium diselenide, 6LiInSe2 or LISe, has promising characteristics for neutron detection applications. The 95% isotopic enrichment of 6Li results in a highly efficient thermal neutron-sensitive material. In this study, we report on a proof-of-principle investigation of a semiconducting LISe pixel detector to demonstrate its potential as an efficient neutron imager. The LISe pixel detector had a 4×4 of pixels with a 550 μm pitch on a 5×5×0.56 mm3 LISe substrate. An experimentally verified spatial resolution of 300 μm was observed utilizing a super-sampling technique.

  2. Pixel detectors from fundamentals to applications

    CERN Document Server

    Rossi, Leonardo; Rohe, Tilman; Wermes, Norbert

    2006-01-01

    Pixel detectors are a particularly important class of particle and radiation detection devices. They have an extremely broad spectrum of applications, ranging from high-energy physics to the photo cameras of everyday life. This book is a general purpose introduction into the fundamental principles of pixel detector technology and semiconductor-based hybrid pixel devices. Although these devices were developed for high-energy ionizing particles and radiation beyond visible light, they are finding new applications in many other areas. This book will therefore benefit all scientists and engineers working in any laboratory involved in developing or using particle detection.

  3. Physics performance of the ATLAS Pixel Detector

    CERN Document Server

    Tsuno, Soshi; The ATLAS collaboration

    2016-01-01

    One noticeable upgrade from Run-1 to Run-2 with ATLAS detector in proton-proton collisions at LHC is the introduction of the new pixel detector, IBL, located on the beam pipe as the extra innermost pixel layer. The tracking and vertex reconstruction are significantly improved and good performance is expected in high level object such a $b$-quark jet tagging, in turn, it leads the better physics results. This note summarizes what is the impact on the IBL detector to the physics results especially focusing on the analyses using the $b$-quark jets throughout 2016 summer physics program.

  4. The pin pixel detector--neutron imaging

    CERN Document Server

    Bateman, J E; Derbyshire, G E; Duxbury, D M; Marsh, A S; Rhodes, N J; Schooneveld, E M; Simmons, J E; Stephenson, R

    2002-01-01

    The development and testing of a neutron gas pixel detector intended for application in neutron diffraction studies is reported. Using standard electrical connector pins as point anodes, the detector is based on a commercial 100 pin connector block. A prototype detector of aperture 25.4 mmx25.4 mm has been fabricated, giving a pixel size of 2.54 mm which matches well to the spatial resolution typically required in a neutron diffractometer. A 2-Dimensional resistive divide readout system has been adapted to permit the imaging properties of the detector to be explored in advance of true pixel readout electronics. The timing properties of the device match well to the requirements of the ISIS-pulsed neutron source.

  5. ATLAS Inner Detector (Pixel Detector and Silicon Tracker)

    CERN Multimedia

    ATLAS Outreach

    2006-01-01

    To raise awareness of the basic functions of the Pixel Detector and Silicon Tracker in the ATLAS detector on the LHC at CERN. This colorful 3D animation is an excerpt from the film "ATLAS-Episode II, The Particles Strike Back." Shot with a bug's eye view of the inside of the detector. The viewer is taken on a tour of the inner workings of the detector, seeing critical pieces of the detector and hearing short explanations of how each works.

  6. Development and performance of a hand-held CZT detector for in-situ measurements at the emergency response

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Young Yong; Chung, Kun Ho; Kim, Chang Jong; Lee, Wan No; Choi, Geun Sik; Kang, Mun Ja [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Yoon, Jin [SI Detection Co. Ltd, Daejeon (Korea, Republic of)

    2016-06-15

    A hand-held detector for an emergency response was developed for nuclide identification and to estimate the information of the ambient dose rate in the scene of an accident as well as the radioactivity of the contaminants. To achieve this, the most suitable sensor was first selected as a cadmium zinc telluride (CZT) semiconductor and the signal processing unit from a sensor and the signal discrimination and storage unit were successfully manufactured on a printed circuit board. The performance of the developed signal processing unit was then evaluated to have an energy resolution of about 14 keV at 662 keV. The system control unit was also designed to operate the CZT detector, monitor the detector, battery, and interface status, and check and transmit the measured results of the ambient dose rate and radioactivity. In addition, a collimator, which can control the inner radius, and the airborne dust sampler, which consists of an air filter and charcoal filter, were developed and mounted to the developed CZT detector for the quick and efficient response of a nuclear accident. The hand-held CZT detector was developed to make the in-situ gamma-ray spectrometry and its performance was checked to have a good energy resolution. In addition, the collimator and the airborne dust sampler were developed and mounted to the developed CZT detector for a quick and efficient response to a nuclear accident.

  7. Upgrade of ATLAS ITk Pixel Detector

    CERN Document Server

    Huegging, Fabian; The ATLAS collaboration

    2017-01-01

    The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenges to the ATLAS tracker. The current inner detector will be replaced with an entirely-silicon inner tracker (ITk) which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation levels are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors and low mass global and local support structures. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the ITk ATLAS Pixel detector developments as well as different layout options will be reviewed.

  8. Radiation hardness studies of silicon pixel detectors

    CERN Document Server

    Lari, T

    2006-01-01

    At the LHC silicon vertex detectors will be exposed to hadron fluences of the order of . In order to study the effects of radiation damage on the performances of the ATLAS Pixel Vertex Detector, several full-size detector modules were irradiated to a fluence of and tested in a beam at CERN. After irradiation only a modest degradation of the detector performances is observed. At the operating ATLAS bias voltage of 600 V the average signal is still 80% of the pre-irradiation value, the spatial resolution is and the detection efficiency is 98.2%. The LHC luminosity upgrade will increase the radiation hardness requirements by a factor of 10 and will require the development of new ultra-radiation hard vertex detectors. A detailed simulation of silicon pixel detectors irradiated to very high fluence is presented and used to study the possibility to use silicon pixel detectors at the LHC after the luminosity upgrade. The charge collection properties and the detector response were computed for different silicon mater...

  9. Towards spark-proof gaseous pixel detectors

    Science.gov (United States)

    Tsigaridas, S.; Beuzekom, M. v.; Chan, H. W.; Graaf, H. v. d.; Hartjes, F.; Heijhoff, K.; Hessey, N. P.; Prodanovic, V.

    2016-11-01

    The micro-pattern gaseous pixel detector, is a promising technology for imaging and particle tracking applications. It is a combination of a gas layer acting as detection medium and a CMOS pixelated readout-chip. As a prevention against discharges we deposit a protection layer on the chip and then integrate on top a micromegas-like amplification structure. With this technology we are able to reconstruct 3D track segments of particles passing through the gas thanks to the functionality of the chip. We have turned a Timepix3 chip into a gaseous pixel detector and tested it at the SPS at Cern. The preliminary results are promising and within the expectations. However, the spark protection layer needs further improvement to make reliable detectors. For this reason, we have created a setup for spark-testing. We present the first results obtained from the lab-measurements along with preliminary results from the testbeam.

  10. Simulation study of pixel detector charge digitization

    Science.gov (United States)

    Wang, Fuyue; Nachman, Benjamin; Sciveres, Maurice; Lawrence Berkeley National Laboratory Team

    2017-01-01

    Reconstruction of tracks from nearly overlapping particles, called Tracking in Dense Environments (TIDE), is an increasingly important component of many physics analyses at the Large Hadron Collider as signatures involving highly boosted jets are investigated. TIDE makes use of the charge distribution inside a pixel cluster to resolve tracks that share one of more of their pixel detector hits. In practice, the pixel charge is discretized using the Time-over-Threshold (ToT) technique. More charge information is better for discrimination, but more challenging for designing and operating the detector. A model of the silicon pixels has been developed in order to study the impact of the precision of the digitized charge distribution on distinguishing multi-particle clusters. The output of the GEANT4-based simulation is used to train neutral networks that predict the multiplicity and location of particles depositing energy inside one cluster of pixels. By studying the multi-particle cluster identification efficiency and position resolution, we quantify the trade-off between the number of ToT bits and low-level tracking inputs. As both ATLAS and CMS are designing upgraded detectors, this work provides guidance for the pixel module designs to meet TIDE needs. Work funded by the China Scholarship Council and the Office of High Energy Physics of the U.S. Department of Energy under contract DE-AC02-05CH11231.

  11. Commissioning of the ATLAS pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    ATLAS Collaboration; Golling, Tobias

    2008-09-01

    The ATLAS pixel detector is a high precision silicon tracking device located closest to the LHC interaction point. It belongs to the first generation of its kind in a hadron collider experiment. It will provide crucial pattern recognition information and will largely determine the ability of ATLAS to precisely track particle trajectories and find secondary vertices. It was the last detector to be installed in ATLAS in June 2007, has been fully connected and tested in-situ during spring and summer 2008, and is ready for the imminent LHC turn-on. The highlights of the past and future commissioning activities of the ATLAS pixel system are presented.

  12. Proceedings of PIXEL98 -- International pixel detector workshop

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D.F.; Kwan, S. [eds.

    1998-08-01

    Experiments around the globe face new challenges of more precision in the face of higher interaction rates, greater track densities, and higher radiation doses, as they look for rarer and rarer processes, leading many to incorporate pixelated solid-state detectors into their plans. The highest-readout rate devices require new technologies for implementation. This workshop reviewed recent, significant progress in meeting these technical challenges. Participants presented many new results; many of them from the weeks--even days--just before the workshop. Brand new at this workshop were results on cryogenic operation of radiation-damaged silicon detectors (dubbed the Lazarus effect). Other new work included a diamond sensor with 280-micron collection distance; new results on breakdown in p-type silicon detectors; testing of the latest versions of read-out chip and interconnection designs; and the radiation hardness of deep-submicron processes.

  13. Affordable CZT SPECT with dose-time minimization (Conference Presentation)

    Science.gov (United States)

    Hugg, James W.; Harris, Brian W.; Radley, Ian

    2017-03-01

    PURPOSE Pixelated CdZnTe (CZT) detector arrays are used in molecular imaging applications that can enable precision medicine, including small-animal SPECT, cardiac SPECT, molecular breast imaging (MBI), and general purpose SPECT. The interplay of gamma camera, collimator, gantry motion, and image reconstruction determines image quality and dose-time-FOV tradeoffs. Both dose and exam time can be minimized without compromising diagnostic content. METHODS Integration of pixelated CZT detectors with advanced ASICs and readout electronics improves system performance. Because historically CZT was expensive, the first clinical applications were limited to small FOV. Radiation doses were initially high and exam times long. Advances have significantly improved efficiency of CZT-based molecular imaging systems and the cost has steadily declined. We have built a general purpose SPECT system using our 40 cm x 53 cm CZT gamma camera with 2 mm pixel pitch and characterized system performance. RESULTS Compared to NaI scintillator gamma cameras: intrinsic spatial resolution improved from 3.8 mm to 2.0 mm; energy resolution improved from 9.8% to molecular imaging, coupled with optimal collimator and image reconstruction, result in minimized dose and exam time. With CZT cost improving, affordable whole-body CZT general purpose SPECT is expected to enable precision medicine applications.

  14. CZT Detector and HXI Development at CASS/UCSD

    Science.gov (United States)

    Rothschild, Richard E.; Tomsick, John A.; Matteson, James L.; Pelling, Michael R.; Suchy, Slawomir

    2006-06-01

    The scientific goals and concept design of the Hard X-ray Imager (HXI) for MIRAX are presented to set the context for a discussion of the status of the HXI development. Emphasis is placed upon the RENA ASIC performance, the detector module upgrades, and a planned high altitude balloon flight to validate the HXI design and performance in a near-space environment.

  15. Application of a CZT detector to in situ environmental radioactivity measurement in the Fukushima area.

    Science.gov (United States)

    Kowatari, M; Kubota, T; Shibahara, Y; Fujii, T; Fukutani, S; Takamiya, K; Mizuno, S; Yamana, H

    2015-11-01

    Instead of conventional Ge semiconductor detectors and NaI(Tl) scintillation spectrometers, an application of a CdZnTe semiconductor (CZT) whose crystal has the dimension of 1 cm cubic to the in situ environmental radioactivity measurement was attempted in deeply affected areas in Fukushima region. Results of deposition density on soil for (134)Cs/(137)Cs obtained seemed consistent, comparing obtained results with those measured by the Japanese government. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Multipixel characterization of imaging CZT detectors for hard X-ray imaging and spectroscopy

    CERN Document Server

    Vadawale, S V; Grindlay, J; Williams, P; Zhang, M; Bellm, E C; Narita, T; Craig, W; Parker, B; Stahle, C; Yan, F; Yan, Feng

    2004-01-01

    We report our in-depth study of Cd-Zn-Te (CZT) crystals to determine an optimum pixel and guard band configuration for Hard X-ray imaging and spectroscopy. We tested 20x20x5mm crystals with 8x8 pixels on a 2.46mm pitch. We have studied different types of cathode / anode contacts and different pixel pad sizes. We present the measurements of leakage current as well as spectral response for each pixel. Our I-V measurement setup is custom designed to allow automated measurements of the I-V curves sequentially for all 64 pixels, whereas the radiation properties measurement setup allows for interchangeable crystals with the same XAIM3.2 ASIC readout from IDEAS. We have tested multiple crystals of each type, and each crystal in different positions to measure the variation between individual crystals and variation among the ASIC channels. We also compare the same crystals with and without a grounded guard band deposited on the crystal side walls vs. a floating guard band and compare results to simulations. This study...

  17. Analysis of CZT crystals and detectors grown in Russia and the Ukraine by high-pressure Bridgman methods

    Energy Technology Data Exchange (ETDEWEB)

    H. Hermon; M. Schieber; R. B. James; E. Y. Lee; N. Yang; A. J. Antolak; D. H. Morse; C. Hackett; E. Tarver; N. N. P. Kolesnikov; Yu N. Ivanov; V. Komar; M. S. Goorsky; H. Yoon

    2000-01-10

    Sandia National Laboratories (SNL) is leading an effort to evaluate vertical high pressure Bridgman (VHPB) Cd{sub 1-x}Zn{sub x}Te (CZT) crystals grown in the former Soviet Union (FSU) (Ukraine and Russia), in order to study the parameters limiting the crystal quality and the radiation detector performance. The stoichiometry of the CZT crystals, with 0.04 < x < 0.25, has been determined by methods such as proton-induced X-ray emission (PIXE), X-ray diffraction (XRD), microprobe analysis and laser ablation ICP mass spectroscopy (LA-ICP/MS). Other methods such as triaxial double crystal x-ray diffraction (TADXRD), infrared transmission spectroscopy (IR), atomic force microscopy (AFM), thermoelectric emission spectroscopy (TEES) and laser induced transient charge technique (TCT) were also used to evaluate the material properties. The authors have measured the zinc distribution in a CZT ingot along the axial direction and also its homogeneity. The (Cd+Zn)/Te average ratio measured on the Ukraine crystals was 1.2, compared to the ratio of 0.9-1.06 on the Russian ingots. The IR transmission showed highly decorated grain boundaries with precipitates and hollow bubbles. Microprobe elemental analysis and LA-ICP/MS showed carbon precipitates in the CZT bulk and carbon deposits along grain boundaries. The higher concentration of impurities and the imperfect crystallinity lead to shorter electron and hole lifetimes in the range of 0.5--2 {micro}s and 0.1 {micro}s respectively, compared to 3--20 {micro}s and 1--7 {micro}s measured on US spectrometer grade CZT detectors. These results are consistent with the lower resistivity and worse crystalline perfection of these crystals, compared to US grown CZT. However, recently grown CZT from FSU exhibited better detector performance and good response to alpha particles.

  18. Use of high-granularity CdZnTe pixelated detectors to correct response non-uniformities caused by defects in crystals

    Science.gov (United States)

    Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; De Geronimo, G.; Eger, J.; Emerick, A.; Fried, J.; Hossain, A.; Roy, U.; Salwen, C.; Soldner, S.; Vernon, E.; Yang, G.; James, R. B.

    2016-01-01

    Following our successful demonstration of the position-sensitive virtual Frisch-grid detectors, we investigated the feasibility of using high-granularity position sensing to correct response non-uniformities caused by the crystal defects in CdZnTe (CZT) pixelated detectors. The development of high-granularity detectors able to correct response non-uniformities on a scale comparable to the size of electron clouds opens the opportunity of using unselected off-the-shelf CZT material, whilst still assuring high spectral resolution for the majority of the detectors fabricated from an ingot. Here, we present the results from testing 3D position-sensitive 15×15×10 mm3 pixelated detectors, fabricated with conventional pixel patterns with progressively smaller pixel sizes: 1.4, 0.8, and 0.5 mm. We employed the readout system based on the H3D front-end multi-channel ASIC developed by BNL's Instrumentation Division in collaboration with the University of Michigan. We use the sharing of electron clouds among several adjacent pixels to measure locations of interaction points with sub-pixel resolution. By using the detectors with small-pixel sizes and a high probability of the charge-sharing events, we were able to improve their spectral resolutions in comparison to the baseline levels, measured for the 1.4-mm pixel size detectors with small fractions of charge-sharing events. These results demonstrate that further enhancement of the performance of CZT pixelated detectors and reduction of costs are possible by using high spatial-resolution position information of interaction points to correct the small-scale response non-uniformities caused by crystal defects present in most devices.

  19. Sensor development for the CMS pixel detector

    CERN Document Server

    Bölla, G; Horisberger, R P; Kaufmann, R; Rohe, T; Roy, A

    2002-01-01

    The CMS experiment which is currently under construction at the Large Hadron Collider (LHC) at CERN (Geneva, Switzerland) will contain a pixel detector which provides in its final configuration three space points per track close to the interaction point of the colliding beams. Because of the harsh radiation environment of the LHC, the technical realization of the pixel detector is extremely challenging. The readout chip as the most damageable part of the system is believed to survive a particle fluence of 6x10 sup 1 sup 4 n sub e sub q /cm sup 2 (All fluences are normalized to 1 MeV neutrons and therefore all components of the hybrid pixel detector have to perform well up to at least this fluence. As this requires a partially depleted operation of the silicon sensors after irradiation-induced type inversion of the substrate, an ''n in n'' concept has been chosen. In order to perform IV-tests on wafer level and to hold accidentally unconnected pixels close to ground potential, a resistive path between the pixe...

  20. Characterization of the CMS Pixel Detectors

    CERN Document Server

    Gu, Weihua

    2002-01-01

    In 2005 the Large Hadron Collider (LHC) will start the pp collisions at a high luminosity and at a center of mass energy of 14 TeV. The primary goal of the experimental programme is the search of the Higgs boson(s) and the supersymmetric particles. The programme is also proposed to detect a range of diverse signatures in order to provide guidance for future physics. The pixel detector system makes up the innermost part of the CMS experiment, which is one of the two general purpose detectors at the LHC. The main tasks of the system are vertex detection and flavor tagging. The high luminosity and the high particle multiplicity as well as the small bunch spacing at the LHC impose great challenges on the pixel detectors: radiation hardness of sensors and electronics, fast signal processing and a high granularity are the essential requirements. This thesis concentrates on the study of the suitability of two test stands, which are implemented to characterize the CMS pixel detectors: one is con-cerned with test puls...

  1. Long-Term Stability of Underground Operated CZT Detectors Based on the Analysis of Intrinsic $^{113}$Cd \\beta$^{-}$-Decay

    CERN Document Server

    Ebert, J; Gehre, D; Hagner, C; Heidrich, N; Klingenberg, R; Kroeninger, K; Nitsch, C; Oldorf, C; Quante, T; Rajek, S; Rebber, H; Rohatsch, K; Tebruegge, J; Temminghoff, R; Theinert, R; Timm, J; Wonsak, B; Zatschler, S; Zuber, K

    2015-01-01

    The COBRA collaboration operates a demonstrator setup at the underground facility LNGS (Laboratori Nazionali del Gran Sasso, located in Italy) to prove the technological capabilities of this concept for the search for neutrinoless double beta-decay. The setup consists of 64 $(1\\times\\!1\\times\\!1)$ cm$^{3}$ CZT detectors in CPG configuration. One purpose of this demonstrator is to test if reliable long-term operation of CZT-CPG detectors in such a setup is possible. The demonstrator has been operated under ultra low-background conditions since more than three years and collected data corresponding to an exposure of 218 kg$\\cdot$days. The presented study focuses on the long-term stability of CZT detectors by analyzing the intrinsic, fourfold forbidden non-unique $^{113}$Cd single beta-decay. It can be shown that CZT detectors can be operated stably for long periods of time and that the $^{113}$Cd single beta-decay can be used as an internal monitor of the detector performance during the runtime of the experimen...

  2. Monolithic pixel detectors for high energy physics

    CERN Document Server

    Snoeys, W

    2013-01-01

    Monolithic pixel detectors integrating sensor matrix and readout in one piece of silicon have revolutionized imaging for consumer applications, but despite years of research they have not yet been widely adopted for high energy physics. Two major requirements for this application, radiation tolerance and low power consumption, require charge collection by drift for the most extreme radiation levels and an optimization of the collected signal charge over input capacitance ratio ( Q / C ). It is shown that monolithic detectors can achieve Q / C for low analog power consumption and even carryout the promise to practically eliminate analog power consumption, but combining suf fi cient Q / C , collection by drift, and integration of readout circuitry within the pixel remains a challenge. An overview is given of different approaches to address this challenge, with possible advantages and disadvantages.

  3. Operational Experience with the ALICE Pixel detector

    CERN Document Server

    Mastroserio, A.

    2017-01-01

    The Silicon Pixel Detector (SPD) constitutes the two innermost layers of the Inner Tracking System of the ALICE experiment and it is the closest detector to the interaction point. As a vertex detector, it has the unique feature of generating a trigger signal that contributes to the L0 trigger of the ALICE experiment. The SPD started collecting data since the very first pp collisions at LHC in 2009 and since then it has taken part in all pp, Pb-Pb and p-Pb data taking campaigns. This contribution will present the main features of the SPD, the detector performance and the operational experience, including calibration and optimization activities from Run 1 to Run 2.

  4. optical links for the atlas pixel detector

    CERN Document Server

    Stucci, Stefania Antonia; The ATLAS collaboration

    2015-01-01

    Optical links are necessary to satisfy the high speed readout over long distances for advanced silicon detector systems. We report on the optical readout used in the newly installed central pixel layer (IBL) in the ATLAS experiment. The off detector readout employs commercial optical to analog converters, which were extensively tested for this application. Performance measurements during installation and commissioning will be shown. With the increasing instantaneous luminosity in the next years, the next layers outwards of IBL of the ATLAS Pixel detector (Layer 1 and Layer 2) will reach their bandwidth limits. A plan to increase the bandwidth by upgrading the off detector readout chain is put in place. The plan also involves new optical readout components, in particular the optical receivers, for which commercial units cannot be used and a new design has been made. The latter allows for a wider operational range in term of data frequency and light input power to match the on-detector sending units on the pres...

  5. Optical links for the ATLAS Pixel detector

    CERN Document Server

    Stucci, Stefania Antonia; The ATLAS collaboration

    2015-01-01

    Optical links are necessary to satisfy the high speed readout over long distances for advanced silicon detector systems. We report on the optical readout used in the newly installed central pixel layer (IBL) in the ATLAS experiment. The off detector readout employs commercial optical to analog converters, which were extensively tested for this application. Performance measurements during installation and commissioning will be shown. With the increasing instantaneous luminosity in the next years, the next layers outwards of IBL of the ATLAS Pixel detector (Layer 1 and Layer 2) will reach their bandwidth limits. A plan to increase the bandwidth by upgrading the off detector readout chain is put in place. The plan also involves new optical readout components, in particular the optical receivers, for which commercial units cannot be used and a new design has been made. The latter allows for a wider operational range in term of data frequency and light input power to match the on-detector sending units on the pres...

  6. Modelling and 3D optimisation of CdTe pixels detector array geometry - Extension to small pixels

    CERN Document Server

    Zumbiehl, A; Fougeres, P; Koebel, J M; Regal, R; Rit, C; Ayoub, M; Siffert, P

    2001-01-01

    CdTe and CdZnTe pixel detectors offer great interest for many applications, especially for medical and industrial imaging. Up to now, the material, generally, used and investigated for pixel arrays was CZT (Hamel et al., IEEE Trans. Nucl. Sci. 43 (3) (1996) 1422; Barrett et al., Phys. Rev. Lett. 75 (1) (1995) 156; Bennett et al., Nucl. Instr. and Meth. A 392 (1997) 260; Eskin et al., J. Appl. Phys. 85 (2) (1999) 647; Brunett et al., J. Appl. Phys. 86 (7) (1999) 3926; Luke, Nucl. Instr. and Meth. A 380 (1996) 232), but cadmium telluride can also be an appropriate choice, as shown here. However, we clearly demonstrate here that the optimal pixel configuration is highly dependent on the electrical transport properties of the material. Depending on the field of primary interest, either energy resolution or counting rate efficiency in the photopeak, the geometry for each case has to be optimised. For that purpose, we have developed a calculation of the signal induced onto the pixel. Two distinct parts are used: af...

  7. The Belle II DEPFET pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Hans-Günther, E-mail: moser@mpp.mpg.de

    2016-09-21

    The Belle II experiment at KEK (Tsukuba, Japan) will explore heavy flavour physics (B, charm and tau) at the starting of 2018 with unprecedented precision. Charged particles are tracked by a two-layer DEPFET pixel device (PXD), a four-layer silicon strip detector (SVD) and the central drift chamber (CDC). The PXD will consist of two layers at radii of 14 mm and 22 mm with 8 and 12 ladders, respectively. The pixel sizes will vary, between 50 μm×(55–60) μm in the first layer and between 50 μm×(70–85) μm in the second layer, to optimize the charge sharing efficiency. These innermost layers have to cope with high background occupancy, high radiation and must have minimal material to reduce multiple scattering. These challenges are met using the DEPFET technology. Each pixel is a FET integrated on a fully depleted silicon bulk. The signal charge collected in the ‘internal gate’ modulates the FET current resulting in a first stage amplification and therefore very low noise. This allows very thin sensors (75 μm) reducing the overall material budget of the detector (0.21% X{sub 0}). Four fold multiplexing of the column parallel readout allows read out a full frame of the pixel matrix in only 20 μs while keeping the power consumption low enough for air cooling. Only the active electronics outside the detector acceptance has to be cooled actively with a two phase CO{sub 2} system. Furthermore the DEPFET technology offers the unique feature of an electronic shutter which allows the detector to operate efficiently in the continuous injection mode of superKEKB.

  8. The Belle II DEPFET pixel detector

    Science.gov (United States)

    Moser, Hans-Günther

    2016-09-01

    The Belle II experiment at KEK (Tsukuba, Japan) will explore heavy flavour physics (B, charm and tau) at the starting of 2018 with unprecedented precision. Charged particles are tracked by a two-layer DEPFET pixel device (PXD), a four-layer silicon strip detector (SVD) and the central drift chamber (CDC). The PXD will consist of two layers at radii of 14 mm and 22 mm with 8 and 12 ladders, respectively. The pixel sizes will vary, between 50 μm×(55-60) μm in the first layer and between 50 μm×(70-85) μm in the second layer, to optimize the charge sharing efficiency. These innermost layers have to cope with high background occupancy, high radiation and must have minimal material to reduce multiple scattering. These challenges are met using the DEPFET technology. Each pixel is a FET integrated on a fully depleted silicon bulk. The signal charge collected in the 'internal gate' modulates the FET current resulting in a first stage amplification and therefore very low noise. This allows very thin sensors (75 μm) reducing the overall material budget of the detector (0.21% X0). Four fold multiplexing of the column parallel readout allows read out a full frame of the pixel matrix in only 20 μs while keeping the power consumption low enough for air cooling. Only the active electronics outside the detector acceptance has to be cooled actively with a two phase CO2 system. Furthermore the DEPFET technology offers the unique feature of an electronic shutter which allows the detector to operate efficiently in the continuous injection mode of superKEKB.

  9. Towards a high sensitivity small animal PET system based on CZT detectors (Conference Presentation)

    Science.gov (United States)

    Abbaszadeh, Shiva; Levin, Craig

    2017-03-01

    Small animal positron emission tomography (PET) is a biological imaging technology that allows non-invasive interrogation of internal molecular and cellular processes and mechanisms of disease. New PET molecular probes with high specificity are under development to target, detect, visualize, and quantify subtle molecular and cellular processes associated with cancer, heart disease, and neurological disorders. However, the limited uptake of these targeted probes leads to significant reduction in signal. There is a need to advance the performance of small animal PET system technology to reach its full potential for molecular imaging. Our goal is to assemble a small animal PET system based on CZT detectors and to explore methods to enhance its photon sensitivity. In this work, we reconstruct an image from a phantom using a two-panel subsystem consisting of six CZT crystals in each panel. For image reconstruction, coincidence events with energy between 450 and 570 keV were included. We are developing an algorithm to improve sensitivity of the system by including multiple interaction events.

  10. The Phase1 CMS Pixel detector upgrade

    CERN Document Server

    Tavolaro, Vittorio Raoul

    2016-01-01

    The pixel detector of the CMS experiment will be replaced in an extended end-of-year shutdown during winter 2016/2017 with an upgraded one able to cope with peak instantaneous luminosities beyond the nominal LHC instantaneous luminosity of $1 \\times 10^{34}$ cm$^{-2}$ s$^{-1}$. Under the conditions expected in the coming years, which will see an increase of a factor two in instantaneous luminosity, the present system would experience a dynamic inefficiency caused mainly by data losses due to buffer overflows. The Phase I upgrade of the CMS pixel detector, described in this paper, will operate at full efficiency at an instantaneous luminosity of $2 \\times 10^{34}$ cm$^{-2}$ s$^{-1}$, thanks to a new readout chip. The new detector will feature one additional tracking point both in the barrel and in the forward regions, while reducing the material budget as a result of a new CO$_{2}$ cooling system and optimised layout of the services. In this paper, the design and the technological choices of the Phase I detect...

  11. Spectroscopic CZT detectors development for x- and gamma-ray imaging instruments

    Science.gov (United States)

    Quadrini, Egidio M.; Uslenghi, Michela; Alderighi, Monica; Casini, Fabio; D'Angelo, Sergio; Fiorini, Mauro; La Palombara, Nicola; Mancini, Marcello; Monti, Serena; Bazzano, Angela; Di Cosimo, Sergio; Frutti, Massimo; Natalucci, Lorenzo; Ubertini, Pietro; Guadalupi, Giuseppe M.; Sassi, Matteo; Negri, Barbara

    2007-09-01

    In the context of R&D studies financed by the Italian Space Agency (ASI), a feasibility study to evaluate the Italian Industry interest in medium-large scale production of enhanced CZT detectors has been performed by an Italian Consortium. The R&D investment aims at providing in-house source of high quality solid state spectrometers for Space Astrophysics applications. As a possible spin-off industrial applications to Gamma-ray devices for non-destructive inspections in medical, commercial and security fields have been considered by ASI. The short term programme mainly consists of developing proprietary procedures for 2-3" CZT crystals growth, including bonding and contact philosophy, and a newly designed low-power electronics readout chain. The prototype design and breadboarding is based on a fast signal AD conversion with the target in order to perform a new run for an already existing low-power (ASIC. The prototype also provides digital photon energy reconstruction with particular care for multiple events and polarimetry evaluations. Scientific requirement evaluations for Space Astrophysics Satellite applications have been carried out in parallel, targeted to contribute to the ESA Cosmic Vision 2015-2025 Announcement of Opportunity. Detailed accommodation studies are undergoing, as part of this programme, to size a "Large area arcsecond angular resolution Imager" for the Gamma Ray Imager satellite (Knödlseder et al., this conference).and a new Gamma-ray Wide Field Camera for the "EDGE" proposal (Piro et al., this conference). Finally, an extended market study for cost analysis evaluation in view of the foreseen massive detector production has been performed.

  12. The ALICE Silicon Pixel Detector System

    CERN Document Server

    Fadmar Osmic, FO

    2006-01-01

    The European Organization for Particle Physics (CERN) in Geneva is currently constructing the Large Hadron Collider (LHC), which will allow the study of the subnuclear ranges of physics with an accuracy never achieved before. Within the LHC project, ALICE is to the study of strongly interacting matter at extreme densities and high temperatures. ALICE as many other modern High Energy Physics (HEP) experiments uses silicon pixel detectors for tracking close to the interaction point (IP). The ALICE Silicon Pixel Detector (SPD) will constitute the two innermost layers of ALICE, and will due to its high granularity provide precise tracking information. In heavy ion collisions, the track density could be as high as 80 tracks/cm2 in the first SPD layer. The SPD will provide tracking information at radii of 3.9 and 7.6 cm from the IP. It is a fundamental element for the study of the weak decays of the particles carrying heavy flavour, whose typical signature will be a secondary vertex separated from the primary verte...

  13. ATLAS rewards two pixel detector suppliers

    CERN Multimedia

    2007-01-01

    Peter Jenni, ATLAS spokesperson, presented the ATLAS supplier award to Herbert Reichl, IZM director, and to Simonetta Di Gioia, from the SELEX company.Two of ATLAS’ suppliers were awarded prizes at a ceremony on Wednesday 13 June attended by representatives of the experiment’s management and of CERN. The prizes went to the Fraunhofer Institut für Zuverlässigkeit und Mikrointegration (IZM) in Berlin and the company SELEX Sistemi Integrati in Rome for the manufacture of modules for the ATLAS pixel detector. SELEX supplied 1500 of the modules for the tracker, while IZM produced a further 1300. The modules, each made up of 46080 channels, form the active part of the ATLAS pixel detector. IZM and SELEX received the awards for the excellent quality of their work: the average number of faulty channels per module was less than 2.10-3. They also stayed within budget and on schedule. The difficulty they faced was designing modules based on electronic components and sensor...

  14. Preliminary research of CZT based PET system development in KAERI

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Woo Jin; Jeong, Man Hee; Kim, Han Soo; Ha, Jang Ho [Advanced Radiation Detection Instrument and Sensor Lab., Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Kim, Sang Yeol [Notice Co., Ltd., Anyang (Korea, Republic of)

    2016-06-15

    For positron emission tomography (PET) application, cadmium zinc telluride (CZT) has been investigated by several institutes to replace detectors from a conventional system using photomultipliers or Silicon-photomultipliers (SiPMs). The spatial and energy resolution in using CZT can be superior to current scintillator-based state-of-the-art PET detectors. CZT has been under development for several years at the Korea Atomic Energy Research Institute (KAERI) to provide a high performance gamma ray detection, which needs a single crystallinity, a good uniformity, a high stopping power, and a wide band gap. Before applying our own grown CZT detectors in the prototype PET system, we investigated preliminary research with a developed discrete type data acquisition (DAQ) system for coincident events at 128 anode pixels and two common cathodes of two CZT detectors from Redlen. Each detector has a 19.4×19.4×6 mm{sup 3} volume size with a 2.2 mm anode pixel pitch. Discrete amplifiers consist of a preamplifier with a gain of 8 mV·fC-1 and noise of 55 equivalent noise charge (ENC), a CR-RC4 shaping amplifier with a 5 μs peak time, and an analog-to-digital converter (ADC) driver. The DAQ system has 65 mega-sample per second flash ADC, a self and external trigger, and a USB 3.0 interface.Characteristics such as the current-to-voltage curve, energy resolution, and electron mobility life-time products for CZT detectors are investigated. In addition, preliminary results of gamma ray imaging using 511 keV of a {sup 22}Na gamma ray source were obtained. In this study, the DAQ system with a CZT radiation sensor was successfully developed and a PET image was acquired by two sets of the developed DAQ system.

  15. Detector performance of the ALICE silicon pixel detector

    CERN Document Server

    Cavicchioli, C

    2011-01-01

    The ALICE Silicon Pixel Detector (SPD) forms the two innermost layers of the ALICE Inner Tracking System (ITS). It consists of two barrel layers of hybrid silicon pixel detectors at radii of 39 and 76 mm. The physics targets of the ALICE experiment require that the material budget of the SPD is kept within approximate to 1\\%X(0) per layer. This has set some stringent constraints on the design and construction of the SPD. A unique feature of the ALICE SPD is that it is capable of providing a prompt trigger signal, called Fast-OR, which contributes to the L0 trigger decision. The pixel trigger system allows to apply a set of algorithms for the trigger selection, and its output is sent to the Central Trigger Processor (CTP). The detector has been installed in the experiment in summer 2007. During the first injection tests in June 2008 the SPD was able to record the very first sign of life of the LHC by registering secondary particles from the beam dumped upstream the ALICE experiment. In the following months the...

  16. Use of high-granularity CdZnTe pixelated detectors to correct response non-uniformities caused by defects in crystals

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov, A.E., E-mail: bolotnik@bnl.gov [Brookhaven National Laboratory, Upton, NY 11793 (United States); Camarda, G.S.; Cui, Y.; De Geronimo, G. [Brookhaven National Laboratory, Upton, NY 11793 (United States); Eger, J.; Emerick, A. [eV Products Inc., Saxonburg, PA 16056 (United States); Fried, J.; Hossain, A.; Roy, U.; Salwen, C. [Brookhaven National Laboratory, Upton, NY 11793 (United States); Soldner, S. [eV Products Inc., Saxonburg, PA 16056 (United States); Vernon, E.; Yang, G.; James, R.B. [Brookhaven National Laboratory, Upton, NY 11793 (United States)

    2016-01-01

    Following our successful demonstration of the position-sensitive virtual Frisch-grid detectors, we investigated the feasibility of using high-granularity position sensing to correct response non-uniformities caused by the crystal defects in CdZnTe (CZT) pixelated detectors. The development of high-granularity detectors able to correct response non-uniformities on a scale comparable to the size of electron clouds opens the opportunity of using unselected off-the-shelf CZT material, whilst still assuring high spectral resolution for the majority of the detectors fabricated from an ingot. Here, we present the results from testing 3D position-sensitive 15×15×10 mm{sup 3} pixelated detectors, fabricated with conventional pixel patterns with progressively smaller pixel sizes: 1.4, 0.8, and 0.5 mm. We employed the readout system based on the H3D front-end multi-channel ASIC developed by BNL's Instrumentation Division in collaboration with the University of Michigan. We use the sharing of electron clouds among several adjacent pixels to measure locations of interaction points with sub-pixel resolution. By using the detectors with small-pixel sizes and a high probability of the charge-sharing events, we were able to improve their spectral resolutions in comparison to the baseline levels, measured for the 1.4-mm pixel size detectors with small fractions of charge-sharing events. These results demonstrate that further enhancement of the performance of CZT pixelated detectors and reduction of costs are possible by using high spatial-resolution position information of interaction points to correct the small-scale response non-uniformities caused by crystal defects present in most devices. - Highlights: • We investigated performances of 3D position sensitive CdZnTe pixelated detectors. • We employed the readout electronics based on H3D ASIC and data processing. • We demonstrated the feasibility of correcting response nonuniformities in CdZnTe pixelated detectors.

  17. Pixel detector modules performance for ATLAS IBL and future pixel detectors

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00355104; Pernegger, Heinz

    2015-11-06

    The ATLAS Detector is one of the four big particle physics experiments at CERN’s LHC. Its innermost tracking system consisted of the 3-Layer silicon Pixel Detector (~80M readout channels) in the first run (2010-2012). Over the past two years it was refurbished and equipped with new services as well as a new beam monitor. The major upgrade, however, was the Insertable B-Layer (IBL). It adds ~12M readout channels for improved vertexing, tracking robustness and b-tagging performance for the upcoming runs, before the high luminosity upgrade of the LHC will take place. This thesis covers two main aspects of Pixel detector performance studies: The main work was the planning, commissioning and operation of a test bench that meets the requirements of current pixel detector components. Each newly built ATLAS IBL stave was thoroughly tested, following a specifically developed procedure, and initially calibrated in that setup. A variety of production accompanying measurements as well as preliminary results after integ...

  18. Silicon buried channels for pixel detector cooling

    Energy Technology Data Exchange (ETDEWEB)

    Boscardin, M., E-mail: boscardi@fbk.eu [Fondazione Bruno Kessler Trento, Via Sommarive 18, I-38123 Trento (Italy); Conci, P.; Crivellari, M.; Ronchin, S. [Fondazione Bruno Kessler Trento, Via Sommarive 18, I-38123 Trento (Italy); Bettarini, S. [Universitá di Pisa, L.go B. Pontecorvo 3, I-56127 Pisa (Italy); Istituto Nazionale di Fisica Nucleare, Sez. di Pisa, L.go B. Pontecorvo 3, I-56127 Pisa (Italy); Bosi, F. [Istituto Nazionale di Fisica Nucleare, Sez. di Pisa, L.go B. Pontecorvo 3, I-56127 Pisa (Italy)

    2013-08-01

    The support and cooling structures add important contributions to the thickness, in radiation length, of vertex detectors. In order to minimize the material budget of pixel sensors, we developed a new approach to integrate the cooling into the silicon devices. The microchannels are formed in silicon using isotropic SF{sub 6} plasma etching in a DRIE (deep reactive ion etcher) equipment. Due to their peculiar profiles, the channels can be sealed by a layer of a PECVD silicon oxide. We have realized on a silicon wafer microchannels with different geometries and hydraulic diameters. We describe the main fabrication steps of microchannels with focus on the channel definition. The experimental results are reported on the thermal characterization of several prototypes, using a mixture of glycol and water as a liquid coolant. The prototypes have shown high cooling efficiency and high-pressure breaking strength.

  19. Hit efficiency study of CMS prototype forward pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dongwook; /Johns Hopkins U.

    2006-01-01

    In this paper the author describes the measurement of the hit efficiency of a prototype pixel device for the CMS forward pixel detector. These pixel detectors were FM type sensors with PSI46V1 chip readout. The data were taken with the 120 GeV proton beam at Fermilab during the period of December 2004 to February 2005. The detectors proved to be highly efficient (99.27 {+-} 0.02%). The inefficiency was primarily located near the corners of the individual pixels.

  20. Near Future Upgrades for the CMS Pixel Detector

    CERN Document Server

    Kumar, Ashish

    2015-01-01

    The silicon pixel detector is the innermost component of the CMS tracking system, providing high precision space point measurements of charged particle trajectories. The current pixel detector is designed to operate at a maximum luminosity of $1\\times10^{34}cm^{-2}s^{-1}$. Before 2018 the instantaneous luminosity of the LHC is expected to reach $2\\times10^{34}cm^{-2}s^{-1}$, which will significantly increase the number of interactions per bunch crossing. The performance of the current pixel detector in such high occupancy environment will be degraded due to substantial data-loss and effects of radiation damage of sensors, built up over the operational period. In order to maintain or exceed its current performance, the CMS pixel detector will be replaced by a new lightweight system with additional detection layers, better acceptance and improved readout electronics. The upgraded pixel detector will provide improved track and vertex reconstruction, standalone tracking capabilities, as well as identification of ...

  1. Crystal growth of CZT and its properties for the application in X-ray and γ-ray detectors

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The paper reports the recent achievement of the research on CZT for the application of X-ray andγ-ray detectors in Northwestern Polytechnical University.The crystals of both un-doped and In doped were grown with a self-designed Bridgman furnace.The microstructure analyses show that the crystals possess high crystallinity.Through In doping,the electronic properties were greatly improved and as high as 5×10~(10)Ωcm resistivity was obtained.The detectors produced with our crystal exhibits high resolutions o...

  2. Status of the CMS Phase I pixel detector upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Spannagel, S., E-mail: simon.spannagel@desy.de

    2016-09-21

    A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a significantly reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These improvements allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. This contribution gives an overview of the design of the upgraded pixel detector and the status of the upgrade project, and presents test beam performance measurements of the production read-out chip.

  3. Status of the CMS Phase I Pixel Detector Upgrade

    CERN Document Server

    AUTHOR|(CDS)2083994

    2016-01-01

    A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase~I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a significantly reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These improvements allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. This contribution gives an overview of the design of the upgraded pixel detector and the status of the upgrade project, and presents test beam performance measurements of the production read-out chip.

  4. Improved CZT for Gamma Detection

    Energy Technology Data Exchange (ETDEWEB)

    JAMES, R.

    2015-03-16

    The goal of the project is to advance the state of the art for spectroscopic and imaging detectors for nonproliferation uses by developing a fundamental understanding of defects limiting the performance of large-volume CZT detectors and fixing them, and increasing the detector size and electron mobility-lifetime product while reducing the cost of detector-grade crystals. Interaction points can be precisely determined in 3D for CZT detectors.

  5. A low mass pixel detector upgrade for CMS

    CERN Document Server

    Kaestli, Hans-Christian

    2010-01-01

    and commissioning of the present pixel detector, we intend to upgrade the whole pixel detector in 2015. The main focus is on lowering the material budget and adding more tracking points. We will present the design of a new low mass pixel system consisting of 4 barrel layers and 3 end cap disks on each side. The design comprises of thin detector modules and a lightweight mechanical support structure using CO2 cooling. In addition, large efforts have been made to move material from the services out of the tracking regi...

  6. Laboratory coded aperture imaging experiments: radial hole coded masks and depth-sensitive CZT detectors

    CERN Document Server

    Hong, J; Zhang, M; Bellm, E C; Yousef, A; Noss, J; Grindlay, J E; Narita, T

    2004-01-01

    The proposed black-hole finder mission EXIST will consist of multiple wide-field hard X-ray coded-aperture telescopes. The high science goals set for the mission require innovations in telescope design. In particular, wide energy band coverage and fine angular resolution require relatively thick coded masks and thick detectors compared to their pixel size, which may introduce mask self-collimation and depth-induced image blurring with conventional design approaches. Previously we proposed relatively simple solutions to these potential problems: radial hole for mask selfcollimation and cathode depth sensing detector for image blurring. We have now performed laboratory experiments to explore the potential of these two techniques. The experimental results show that the radial hole mask greatly alleviates mask self-collimation and a ~1 mm resolution depth-sensitive detector scheme can be relatively easily achieved for the large scale required for EXIST.

  7. Diamond and silicon pixel detectors in high radiation environments

    Energy Technology Data Exchange (ETDEWEB)

    Tsung, Jieh-Wen

    2012-10-15

    Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10{sup 16} particles per cm{sup 2}, which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10{sup 15} particles per cm{sup 2}.

  8. Online calibrations and performance of the ATLAS Pixel Detector

    CERN Document Server

    Keil, M; The ATLAS collaboration

    2010-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. It consists of 1744 silicon sensors equipped with approximately 80 M electronic channels, providing typically three measurement points with high resolution for particles emerging from the beam-interaction region, thus allowing measuring particle tracks and secondary vertices with very high precision. The readout system of the Pixel Detector is based on a bi-directional optical data transmission system between the detector and the data acquisition system with an individual link for each of the 1744 modules. Signal conversion components are located on both ends, approximately 80 m apart. The talk will give an overview of the calibration and performance of both the detector and its optical readout. The most basic parameter to be tuned and calibrated for the detector electronics is the readout threshold of the individual pixel channels. These need to be carefully tuned to optimise position resolution a...

  9. DAQ Hardware and software development for the ATLAS Pixel Detector

    CERN Document Server

    Stramaglia, Maria Elena; The ATLAS collaboration

    2015-01-01

    In 2014, the Pixel Detector of the ATLAS experiment was extended by about 12 million pixels with the installation of the Insertable B-Layer (IBL). Data-taking and tuning procedures have been implemented by employing newly designed read-out hardware, which supports the full detector bandwidth even for calibration. The hardware is supported by an embedded software stack running on the read-out boards. The same boards will be used to upgrade the read-out bandwidth for the two outermost layers of the ATLAS Pixel Barrel (54 million pixels). We present the IBL read-out hardware and the supporting software architecture used to calibrate and operate the 4-layer ATLAS Pixel detector. We discuss the technical implementations and status for data taking, validation of the DAQ system in recent cosmic ray data taking, in-situ calibrations, and results from additional tests in preparation for Run 2 at the LHC.

  10. Detector apparatus having a hybrid pixel-waveform readout system

    Science.gov (United States)

    Meng, Ling-Jian

    2014-10-21

    A gamma ray detector apparatus comprises a solid state detector that includes a plurality of anode pixels and at least one cathode. The solid state detector is configured for receiving gamma rays during an interaction and inducing a signal in an anode pixel and in a cathode. An anode pixel readout circuit is coupled to the plurality of anode pixels and is configured to read out and process the induced signal in the anode pixel and provide triggering and addressing information. A waveform sampling circuit is coupled to the at least one cathode and configured to read out and process the induced signal in the cathode and determine energy of the interaction, timing of the interaction, and depth of interaction.

  11. The Protoexist2 Advanced CZT Coded Aperture Telescope

    Science.gov (United States)

    Allen, Branden; Hong, J.; Grindlay, J.; Barthelmy, S.; Baker, R.

    2011-09-01

    The ProtoEXIST program was conceived for the development of a scalable detector plane architecture utilizing pixilated CdZnTe (CZT) detectors for eventual deployment in a large scale (1-4 m2 active area) coded aperture X-ray telescope for use as a wide field ( 90° × 70° FOV) all sky monitor and survey instrument for the 5 up to 600 keV energy band. The first phase of the program recently concluded with the successful 6 hour high altitude (39 km) flight of ProtoEXIST1, which utilized a closely tiled 8 × 8 array of 20 mm × 20 mm, 5 mm thick Redlen CZT crystals each bonded to a RadNET asic via an interposer board. Each individual CZT crystal utilized a 8 × 8 pixilated anode for the creation of a position sensitive detector with 2.5 mm spatial resolution. Development of ProtoEXIST2, the second advanced CZT detector plane in this series, is currently under way. ProtoEXIST2 will be composed of a closely tiled 8 × 8 array of 20 mm × 20 mm, 5 mm thick Redlen CZT crystals, similar to ProtoEXIST1, but will now utilize the Nu-ASIC which accommodates the direct bonding of CZT detectors with a 32 × 32 pixilated anode with a 604.8 μm pixel pitch. Characterization and performance of the ProtoEXIST2 detectors is discussed as well as current progress in the integration of the ProtoEXIST2 detector plane.

  12. Data encoding efficiency in pixel detector readout with charge information

    CERN Document Server

    Garcia-Sciveres, Maurice

    2016-01-01

    The minimum number of bits needed for lossless readout of a pixel detector is calculated, in the regime of interest for particle physics where only a small fraction of pixels have a non-zero value per frame. This permits a systematic comparison of the readout efficiency of different encoding implementations. The calculation is compared to the bits used for by the FE-I4 pixel readout chip of the ATLAS experiment.

  13. Data encoding efficiency in pixel detector readout with charge information

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Sciveres, Maurice, E-mail: mgs@lbl.gov [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Wang, Xinkang [University of Chicago, Chicago, IL (United States)

    2016-04-11

    The average minimum number of bits needed for lossless readout of a pixel detector is calculated, in the regime of interest for particle physics where only a small fraction of pixels have a non-zero value per frame. This permits a systematic comparison of the readout efficiency of different encoding implementations. The calculation is compared to the number of bits used by the FE-I4 pixel readout chip of the ATLAS experiment.

  14. Monolithic CMOS pixel detector for international linear collider vertex detection

    Indian Academy of Sciences (India)

    J E Brau; O Igonkina; N Sinew; D Strom; C Baltay; W Emmet; H Neal; D Rabinowitz

    2007-12-01

    A monolithic CMS pixel detector is under development for an ILC experiment. This chronopixel array provides a time stamp resolution of one bunch crossing, a critical feature for background suppression. The status of this effort is summarized.

  15. The pin pixel detector--X-ray imaging

    CERN Document Server

    Bateman, J E; Derbyshire, G E; Duxbury, D M; Marsh, A S; Simmons, J E; Stephenson, R

    2002-01-01

    The development and testing of a soft X-ray gas pixel detector, which uses connector pins for the anodes is reported. Based on a commercial 100 pin connector block, a prototype detector of aperture 25.4 mm centre dot 25.4 mm can be economically fabricated. The individual pin anodes all show the expected characteristics of small gas detectors capable of counting rates reaching 1 MHz per pin. A 2-dimensional resistive divide readout system has been developed to permit the imaging properties of the detector to be explored in advance of true pixel readout electronics.

  16. Silicon Pixel Detectors for Synchrotron Applications

    CERN Document Server

    Stewart, Graeme Douglas

    Recent advances in particle accelerators have increased the demands being placed on detectors. Novel detector designs are being implemented in many different areas including, for example, high luminosity experiments at the LHC or at next generation synchrotrons. The purpose of this thesis was to characterise some of these novel detectors. The first of the new detector types is called a 3D detector. This design was first proposed by Parker, Kenney and Segal (1997). In this design, doped electrodes are created that extend through the silicon substrate. When compared to a traditional photodiode with electrodes on the opposing surfaces, the 3D design can combine a reasonable detector thickness with a small electrode spacing resulting in fast charge collection and limited charge sharing. The small electrode spacing leads to the detectors having lower depletion voltages. This, combined with the fast collection time, makes 3D detectors a candidate for radiation hard applications. These applications include the upgra...

  17. The Phase-1 Upgrade of the CMS Pixel Detector

    CERN Document Server

    Klein, Katja

    2016-01-01

    The CMS experiment features a pixel detector with three barrel layers and two disks per side, corresponding to an active silicon area of 1\\,m$^2$. The detector delivered high-quality data during LHC Run~1. However, the CMS pixel detector was designed for the nominal instantaneous LHC luminosity of $1\\cdot 10^{34}\\,$cm$^{-2}$s$^{-1}$. It is expected that the instantaneous luminosity will increase and reach twice the design value before Long Shutdown 3, scheduled for 2023. Under such conditions, the present readout chip would suffer from data loss due to buffer overflow, leading to significant inefficiencies of up to~16\\,\\%. The CMS collaboration is presently constructing a new pixel detector to replace the present device during the winter shutdown 2016/2017. The design of this new detector will be outlined, the construction status summarized and the performance described.

  18. The Phase-1 upgrade of the CMS silicon pixel detector

    CERN Document Server

    Menichelli, Mauro

    2015-01-01

    The present CMS pixel detector will be replaced in the shutdown period 2016/17 by an upgraded version due to the following reasons: increased luminosity at reduced bunch spacing ( from 7 x 10 33 cm - 2 s - 1 at 50 ns bunch spacing to 2 x 10 34 cm - 2 s - 1 at 25 ns bunch spacing) in the LHC , and radiation damage effects that will significantly degrade the present detector. The new upgraded detector will have higher tracking efficiency and lower mass with four barrel layer and three forward/backward disks to provide higher hit pixel coverage out to pseudorapidities of ±2.5. In this paper we will describe the new pixel detector focus ing mostly on the barrel detector design, construction and expected performances

  19. The Phase-1 upgrade of the CMS pixel detector

    Science.gov (United States)

    Klein, Katja

    2017-02-01

    The CMS experiment features a pixel detector with three barrel layers and two discs per side, corresponding to an active silicon area of 1 m2. The detector delivered high-quality data during LHC Run 1. However, the CMS pixel detector was designed for the nominal instantaneous LHC luminosity of 1 ·1034cm-2s-1 . It is expected that the instantaneous luminosity will increase and reach twice the design value before Long Shutdown 3, scheduled for 2023. Under such conditions, the present readout chip would suffer from data loss due to buffer overflow, leading to significant inefficiencies of up to 16%. The CMS collaboration is presently constructing a new pixel detector to replace the present device during the winter shutdown 2016/2017. The design of this new detector will be outlined, the construction status summarized and the performance described.

  20. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Nachman, Benjamin Philip; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of $10^{15}$ 1 MeV $n_\\mathrm{eq}/\\mathrm{cm}^2$ and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This talk presents a digitization model that includes radiation damage effects to the ATLAS Pixel sensors for the first time. After a thorough description of the setup, predictions for basic Pixel cluster properties are presented alongside first validation studies with Run 2 collision data.

  1. Operational Experience with the ATLAS Pixel Detector at LHC

    CERN Document Server

    Keil, M

    2013-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus crucial for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via front-end chips bump-bonded to 1744 n-on-n silicon substrates. In this paper results from the successful operation of the Pixel Detector at the LHC will be presented, including calibration procedures, detector performance and measurements of radiation damage. The detector performance is excellent: more than 95% of the pixels are operational, noise occupancy and hit efficiency exceed the des...

  2. Pixel-level Analog-To-Digital Converters for Hybrid Pixel Detectors with energy sensitivity

    NARCIS (Netherlands)

    San Segundo Bello, David; Nauta, Bram; Visschers, Jan

    2000-01-01

    Single-photon counting hybrid pixel detectors have shown to be a valid alternative to other types of X-ray imaging devices due to their high sensitivity, low noise, linear behavior and wide dynamic range. One important advantage of these devices is the fact that detector and readout electronics are

  3. Design of pixel-level ADCs for energy-sensitive hybrid pixel detectors

    NARCIS (Netherlands)

    San Segundo Bello, David; Nauta, Bram; Visschers, Jan

    2000-01-01

    Single-photon counting hybrid pixel detectors have shown to be a valid alternative to other types of X-ray imaging devices due to their high sensitivity, low noise, linear behavior and wide dynamic range. One important advantage of these devices is the fact that detector and readout electronics are

  4. Characterization of coplanar grid CZT detectors with highly collimated x-ray beam

    Science.gov (United States)

    Carini, Gabriella A.; Bolotnikov, Aleksey E.; Camarda, Giuseppe S.; Wright, Gomez W.; De Geronimo, Gianluigi; Siddons, D. P.; James, Ralph B.

    2004-10-01

    CdZnTe detectors demonstrated great potentials for detection of gamma radiation. However, energy resolution of CdZnTe detectors is significantly affected by uncollected holes which have low mobility and short lifetime. To overcome this deleterious effects upon energy resolution special detector designs have to be implemented. The most practical of them are the small pixel effect device, the co-planar grid device, and the virtual Frisch-grid device. We routinely use a highly collimated high-intensity X-ray beams provided by National Synchrotron Light Source (NSLS) facility at Brookhaven National Laboratory to study of CdZnTe material and performances of the different types of devices on the micron-scale. This powerful tool allows us to evaluate electronic properties of the material, device performance, uniformity of the detector responses, effects related to the device's contact pattern and electric field distribution, etc. In particular, in this paper we present new results obtained from the performance studies of 15 x 15 x 7.5 mm3 coplanar-grid devices coupled to readout ASIC. We observed the effect of the strip contacts comprising the grids on the energy resolution of the coplanar-grid device.

  5. Characterization of active CMOS sensors for capacitively coupled pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Hirono, Toko; Gonella, Laura; Janssen, Jens; Hemperek, Tomasz; Huegging, Fabian; Krueger, Hans; Wermes, Norbert [Institute of Physics, University of Bonn (Germany); Peric, Ivan [Institut fuer Prozessdatenverarbeitung und Elektronik, Karlsruher Institut fuer Technologie, Karlsruhe (Germany)

    2015-07-01

    Active CMOS pixel sensor is one of the most attractive candidates for detectors of upcoming particle physics experiments. In contrast to conventional sensors of hybrid detectors, signal processing circuit can be integrated in the active CMOS sensor. The characterization and optimization of the pixel circuit are indispensable to obtain a good performance from the sensors. The prototype chips of the active CMOS sensor were fabricated in the AMS 180nm and L-Foundry 150 nm CMOS processes, respectively a high voltage and high resistivity technology. Both chips have a charge sensitive amplifier and a comparator in each pixel. The chips are designed to be glued to the FEI4 pixel readout chip. The signals from 3 pixels of the prototype chips are capacitively coupled to the FEI4 input pads. We have performed lab tests and test beams to characterize the prototypes. In this presentation, the measurement results of the active CMOS prototype sensors are shown.

  6. Neural network based cluster creation in the ATLAS Pixel Detector

    CERN Document Server

    Andreazza, A; The ATLAS collaboration

    2012-01-01

    The read-out from individual pixels on planar semi-conductor sensors are grouped into clusters to reconstruct the location where a charged particle passed through the sensor. The resolution given by individual pixel sizes is significantly improved by using the information from the charge sharing be- tween pixels. Such analog cluster creation techniques have been used by the ATLAS experiment for many years to obtain an excellent performance. How- ever, in dense environments, such as those inside high-energy jets, clusters have an increased probability of merging the charge deposited by multiple particles. Recently, a neural network based algorithm which estimates both the cluster position and whether a cluster should be split has been developed for the ATLAS Pixel Detector. The algorithm significantly reduces ambigui- ties in the assignment of pixel detector measurement to tracks and improves the position accuracy with respect to standard techniques by taking into account the 2-dimensional charge distribution.

  7. DAQ hardware and software development for the ATLAS Pixel Detector

    CERN Document Server

    Stramaglia, Maria Elena; The ATLAS collaboration

    2015-01-01

    In 2014, the Pixel Detector of the ATLAS experiment has been extended by about 12 million pixels thanks to the installation of the Insertable B-Layer (IBL). Data-taking and tuning procedures have been implemented along with newly designed read-out hardware to support high bandwidth for data readout and calibration. The hardware is supported by an embedded software stack running on the read-out boards. The same boards will be used to upgrade the read-out bandwidth for the two outermost layers of the ATLAS Pixel Barrel (54 million pixels). We present the IBL read-out hardware and the supporting software architecture used to calibrate and operate the 4-layer ATLAS Pixel detector. We discuss the technical implementations and status for data taking, validation of the DAQ system in recent cosmic ray data taking, in-situ calibrations, and results from additional tests in preparation for Run 2 at the LHC.

  8. Challenges of small-pixel infrared detectors: a review

    Science.gov (United States)

    Rogalski, A.; Martyniuk, P.; Kopytko, M.

    2016-04-01

    In the last two decades, several new concepts for improving the performance of infrared detectors have been proposed. These new concepts particularly address the drive towards the so-called high operating temperature focal plane arrays (FPAs), aiming to increase detector operating temperatures, and as a consequence reduce the cost of infrared systems. In imaging systems with the above megapixel formats, pixel dimension plays a crucial role in determining critical system attributes such as system size, weight and power consumption (SWaP). The advent of smaller pixels has also resulted in the superior spatial and temperature resolution of these systems. Optimum pixel dimensions are limited by diffraction effects from the aperture, and are in turn wavelength-dependent. In this paper, the key challenges in realizing optimum pixel dimensions in FPA design including dark current, pixel hybridization, pixel delineation, and unit cell readout capacity are outlined to achieve a sufficiently adequate modulation transfer function for the ultra-small pitches involved. Both photon and thermal detectors have been considered. Concerning infrared photon detectors, the trade-offs between two types of competing technology—HgCdTe material systems and III-V materials (mainly barrier detectors)—have been investigated.

  9. The phase 1 upgrade of the CMS pixel detector

    CERN Document Server

    Verzocchi, Marco

    2016-01-01

    The CMS collaboration is building a replacement for the pixel detector that will be installed in the extended end of year shutdown 2016-2017. This contribution reviews the motivations for the upgrade, the technological choices made, the status of the construction of this new detector and the plans for installation and commissioning.

  10. Fabrication of ATLAS pixel detector prototypes at IRST

    CERN Document Server

    Boscardin, M; Gregori, P; Zen, M; Zori, N

    2001-01-01

    We report on the development of a fabrication technology for n-on-n silicon pixel detectors oriented to the ATLAS experiment at LHC. The main processing issues and some selected results from the electrical characterization of detector prototypes and related test structures are presented and discussed. (5 refs).

  11. Charge induction in semiconductor detectors with pixellated structure

    NARCIS (Netherlands)

    Samedov, Victor V.

    2007-01-01

    Considerable interest is now being attracted to the next generation of compound semiconductor detectors with pixellated structure in application to x-ray and gamma-astronomy, nuclear spectroscopy and nuclear medicine. The spatial resolution of this type of detectors is mainly determined by the proce

  12. Long-term stability of underground operated CZT detectors based on the analysis of intrinsic {sup 113}Cd β{sup −}-decay

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, J. [Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Gößling, C. [Technische Universität Dortmund, Lehrstuhl für Experimentelle Physik IV, Otto-Hahn-Str 4, 44221 Dortmund (Germany); Gehre, D., E-mail: daniel.gehre@tu-dresden.de [Technische Universität Dresden, Institut für Kern- und Teilchenphysik, Zellescher Weg 19, 01069 Dresden (Germany); Hagner, C.; Heidrich, N. [Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Klingenberg, R.; Kröninger, K.; Nitsch, C. [Technische Universität Dortmund, Lehrstuhl für Experimentelle Physik IV, Otto-Hahn-Str 4, 44221 Dortmund (Germany); Oldorf, C. [Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Quante, T.; Rajek, S. [Technische Universität Dortmund, Lehrstuhl für Experimentelle Physik IV, Otto-Hahn-Str 4, 44221 Dortmund (Germany); Rebber, H.; Rohatsch, K. [Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Tebrügge, J.; Temminghoff, R.; Theinert, R. [Technische Universität Dortmund, Lehrstuhl für Experimentelle Physik IV, Otto-Hahn-Str 4, 44221 Dortmund (Germany); and others

    2016-06-11

    The COBRA collaboration operates a demonstrator setup at the underground facility Laboratori Nazionali del Gran Sasso (LNGS, located in Italy) to prove the technological capabilities of this concept for the search for neutrinoless double beta-decay. The setup consists of 64 (1×1×1) cm{sup 3} Cadmium-Zinc-Telluride (CZT) detectors in Coplanar-Grid (CPG) configuration. One purpose of this demonstrator is to test if reliable long-term operation of CZT-CPG detectors in such a setup is possible. The demonstrator has been operated under ultra low-background conditions for more than three years and collected data corresponding to a total exposure of 218 kg days. The presented study focuses on the long-term stability of CZT detectors by analyzing the intrinsic, fourfold forbidden non-unique {sup 113}Cd single beta-decay. It can be shown that CZT detectors can be operated stably for long periods of time and that the {sup 113}Cd single beta-decay can be used as an internal monitor of the detector performance during the runtime of the experiment.

  13. A low mass pixel detector upgrade for CMS

    CERN Document Server

    Kästli, H C

    2010-01-01

    The CMS pixel detector has been designed for a peak luminosity of 10^34cm-2s-1 and a total dose corresponding to 2 years of LHC operation at a radius of 4 cm from the interaction region. Parts of the pixel detector will have to be replaced until 2015. The detector performance will be degraded for two reasons: radiation damage of the innermost layers and the planned increase of the LHC peak luminosity by a factor of 2-3. Based on the experience in planning, constructing and commissioning of the present pixel detector, we intend to upgrade the whole pixel detector in 2015. The main focus is on lowering the material budget and adding more tracking points. We will present the design of a new low mass pixel system consisting of 4 barrel layers and 3 end cap disks on each side. The design comprises of thin detector modules and a lightweight mechanical support structure using CO2 cooling. In addition, large efforts have been made to move material from the services out of the tracking region.

  14. Pixels simultaneous detection probabilities and spatial resolution determination of pixelized detectors by means of correlation measurements

    CERN Document Server

    Grabskii, V

    2007-01-01

    A novel method to estimate the pixels simultaneous detection probability and the spatial resolution of pixelized detectors is proposed, which is based on the determination of the statistical correlations between detector neighbor pixels. The correlations are determined by means of noise variance measurement for a isolated pixels and the difference between neighbor pixels. The method is validated using images from the two different GE Senographe 2000D mammographic units. The pixelized detector has been irradiated using x-rays along its entire surface. It is shown that the pixel simultaneous detection probabilities can be estimated within accuracy 0.001 - 0.003, where the systematic error is estimated to be smaller than 0.005. The presampled two-dimensional point-spread function (PSF0) is determined using a single Gaussian and a sum of two Gaussian approximations. The obtained results for the presampled PSF0 show that the single Gaussian approximation is not appropriate, and the sum of two Gaussian approximatio...

  15. Array of virtual Frisch-grid CZT detectors with common cathode readout and pulse-height correction

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov, A.E.; Camarda, G.S.; Cui, Y.; Egarievwe, E.U.; Fochuk, P.M.; Fuerstnau, M.; Gul, R.; Hossain, A.; Jones, F.; Kim, K.; Kopach, O.V.; Taggart, R.; Yang, G.; Ye, Z.; Xu, L.; and James, R.B.

    2010-08-01

    We present our new results from testing 15-mm-long virtual Frisch-grid CdZnTe detectors with a common-cathode readout for correcting pulse-height distortions. The array employs parallelepiped-shaped CdZnTe (CZT) detectors of a large geometrical aspect ratio, with two planar contacts on the top and bottom surfaces (anode and cathode) and an additional shielding electrode on the crystal's sides to create the virtual Frisch-grid effect. We optimized the geometry of the device and improved its spectral response. We found that reducing to 5 mm the length of the shielding electrode placed next to the anode had no adverse effects on the device's performance. At the same time, this allowed corrections for electron loss by reading the cathode signals to obtain depth information.

  16. Operational experience of ATLAS SCT and Pixel Detector

    CERN Document Server

    Kocian, Martin; The ATLAS collaboration

    2017-01-01

    The ATLAS Inner Detector based on silicon sensors is consisting of a strip detector (SCT) and a pixel detector. It is the crucial component for vertexing and tracking in the ATLAS experiment. With the excellent performance of the LHC well beyond the original specification the silicon tracking detectors are facing substantial challenges in terms of data acquisition, radiation damage to the sensors, and SEUs in the readout ASICs. The approaches on how the detector systems cope with the demands of high luminosity operation while maintaining excellent performance through hardware upgrades, software and firmware algorithms, and operational settings, are presented.

  17. Hybrid Pixel Detectors for gamma/X-ray imaging

    Science.gov (United States)

    Hatzistratis, D.; Theodoratos, G.; Zografos, V.; Kazas, I.; Loukas, D.; Lambropoulos, C. P.

    2015-09-01

    Hybrid pixel detectors are made by direct converting high-Z semi-insulating single crystalline material coupled to complementary-metal-oxide semiconductor (CMOS) readout electronics. They are attractive because direct conversion exterminates all the problems of spatial localization related to light diffusion, energy resolution, is far superior from the combination of scintillation crystals and photomultipliers and lithography can be used to pattern electrodes with very fine pitch. We are developing 2-D pixel CMOS ASICs, connect them to pixilated CdTe crystals with the flip chip and bump bonding method and characterize the hybrids. We have designed a series of circuits, whose latest member consists of a 50×25 pixel array with 400um pitch and an embedded controller. In every pixel a full spectroscopic channel with time tagging information has been implemented. The detectors are targeting Compton scatter imaging and they can be used for coded aperture imaging too. Hybridization using CMOS can overcome the limit put on pixel circuit complexity by the use of thin film transistors (TFT) in large flat panels. Hybrid active pixel sensors are used in dental imaging and other applications (e.g. industrial CT etc.). Thus X-ray imaging can benefit from the work done on dynamic range enhancement methods developed initially for visible and infrared CMOS pixel sensors. A 2-D CMOS ASIC with 100um pixel pitch to demonstrate the feasibility of such methods in the context of X-ray imaging has been designed.

  18. Performance of silicon pixel detectors at small track incidence angles

    CERN Document Server

    Viel, Simon; The ATLAS collaboration

    2015-01-01

    In order to enable the ATLAS experiment to successfully track charged particles produced in high-energy collisions at the High-Luminosity Large Hadron Collider, the current ATLAS Inner Detector will be replaced by the Inner Tracker (ITk), entirely composed of silicon pixel and strip detectors. An extension of the tracking coverage of ITk to very forward pseudorapidity values is proposed, using pixel modules placed in a long cylindrical layer around the beam pipe. The measurement of long pixel clusters, detected when charged particles cross the silicon sensor at small incidence angles, has potential to significantly improve the tracking efficiency, fake track rejection, and resolution of ITk in the very forward region. The performance of state-of-the-art pixel modules at small track incidence angles is studied using test beam data collected at SLAC and CERN, as well as simulated data.

  19. The ATLAS tracker Pixel detector for HL-LHC

    CERN Document Server

    Gemme, Claudia; The ATLAS collaboration

    2017-01-01

    The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenges to the ATLAS tracker. The current Inner Detector will be replaced with a whole silicon tracker which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation levels are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the HL-LHC ATLAS Pixel detector developments as well as the various layout options are reviewed.

  20. Online Calibration and Performance of the ATLAS Pixel Detector

    CERN Document Server

    Keil, M

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. It consists of 1744 silicon sensors equipped with approximately 80 million electronic channels, providing typically three measurement points with high resolution for particles emerging from the beam-interaction region, thus allowing measuring particle tracks and secondary vertices with very high precision. The readout system of the Pixel Detector is based on a bi-directional optical data transmission system between the detector and the data acquisition system with an individual link for each of the 1744 modules. Signal conversion components are located on both ends, approximately 80 m apart. This paper describes the tuning and calibration of the optical links and the detector modules, including measurements of threshold, noise, charge measurement, timing performance and the sensor leakage current.

  1. Alignment of the VELO pixel detector

    CERN Document Server

    Petersson Sjogren, Anna

    2017-01-01

    The LHCb experiment is designed to perform high precision measurements to study CP-violation and rare decays of beauty and charm hadrons. During LS2, prior to Run 3 of the LHC, the LHCb detector will go through a major upgrade. One of the sub-detectors that will be upgraded is the Vertex Locator (VELO) which after the upgrade will be capable of readout at 40 MHz at a luminosity of 2· 1033 cm−2s−1. VELO is a high precision detector designed to reconstruct and discriminate between primary and secondary vertices close to the interaction point. Due to safety of the detector, the VELO is divided into two retractable halves which prior to each fill into LHC are retracted from the beam-line, and closed once stable beam is declared. Best possible performance of the VELO requires the halves of the VELO, and the individual detector elements of it, to be aligned for correct reconstruction of tracks and vertices.

  2. Leakage current measurements on pixelated CdZnTe detectors

    NARCIS (Netherlands)

    Dirks, B.P.F.; Blondel, C.; Daly, F.; Gevin, O.; Limousin, O.; Lugiez, F.

    2006-01-01

    In the field of the R&D of a new generation hard X-ray cameras for space applications we focus on the use of pixelated CdTe or CdZnTe semiconductor detectors. They are covered with 64 (0.9×0.9 mm2) or 256 (0.5×0.5 mm2) pixels, surrounded by a guard ring and operate in the energy ranging from several

  3. Silicon pixel detector prototyping in SOI CMOS technology

    Science.gov (United States)

    Dasgupta, Roma; Bugiel, Szymon; Idzik, Marek; Kapusta, Piotr; Kucewicz, Wojciech; Turala, Michal

    2016-12-01

    The Silicon-On-Insulator (SOI) CMOS is one of the most advanced and promising technology for monolithic pixel detectors design. The insulator layer that is implemented inside the silicon crystal allows to integrate sensors matrix and readout electronic on a single wafer. Moreover, the separation of electronic and substrate increases also the SOI circuits performance. The parasitic capacitances to substrate are significantly reduced, so the electronic systems are faster and consume much less power. The authors of this presentation are the members of international SOIPIX collaboration, that is developing SOI pixel detectors in 200 nm Lapis Fully-Depleted, Low-Leakage SOI CMOS. This work shows a set of advantages of SOI technology and presents possibilities for pixel detector design SOI CMOS. In particular, the preliminary results of a Cracow chip are presented.

  4. Calibration Analysis Software for the ATLAS Pixel Detector

    CERN Document Server

    Stramaglia, Maria Elena; The ATLAS collaboration

    2015-01-01

    The calibration of the ATLAS Pixel detector at LHC fulfils two main purposes: to tune the front-end configuration parameters for establishing the best operational settings and to measure the tuning performance through a subset of scans. An analysis framework has been set up in order to take actions on the detector given the outcome of a calibration scan (e.g. to create a mask for disabling noisy pixels). The software framework to control all aspects of the Pixel detector scans and analyses is called Calibration Console. The introduction of a new layer, equipped with new Front End-I4 Chips, required an update the Console architecture. It now handles scans and scans analyses applied together to chips with different characteristics. An overview of the newly developed Calibration Analysis Software will be presented, together with some preliminary result.

  5. Calibration Analysis Software for the ATLAS Pixel Detector

    CERN Document Server

    Stramaglia, Maria Elena; The ATLAS collaboration

    2015-01-01

    The calibration of the Pixel detector fulfills two main purposes: to tune front-end registers for establishing the best operational settings and to measure the tuning performance through a subset of scans. An analysis framework has been set up in order to take actions on the detector given the outcome of a calibration scan (e.g. to create a mask for disabling noisy pixels). The software framework to control all aspects of the Pixel detector scans and analyses is called Calibration Console. The introduction of a new layer, equipped with new Front End-I4 Chips, required an update the Console architecture. It now handles scans and scans analyses applied toghether to chips with dierent characteristics. An overview of the newly developed Calibration Analysis Software will be presented, together with some preliminary result.

  6. Detector Modules for the CMS Pixel Phase 1 Upgrade

    CERN Document Server

    Zhu, De Hua; Berger, Pirmin; Meinhard, Maren Tabea; Starodumov, Andrey; Tavolaro, Vittorio Raoul

    2017-01-01

    The CMS Pixel phase 1 upgrade detector consists of 1184 modules with new design. An important part of the production is the module qualification and calibration, ensuring their proper functionality within the detector. This paper summarizes the qualification and calibration results of modules used in the innermost two detector layers with focus on methods using module-internal calibration signals. Extended characterizations on pixel level such as electronic noise and bump bond connectivity, optimization of operational parameters, sensor quality and thermal stress resistance were performed using a customized setup with controlled environment. It could be shown that the selected modules have on average $0.55 \\mathrm{ {}^{0\\!}\\!/\\!_{00} }\\, \\pm \\, 0.01 \\mathrm{ {}^{0\\!}\\!/\\!_{00} }\\,$ defective pixels and that all performance parameters stay within their specifications.

  7. Calibration analysis software for the ATLAS Pixel Detector

    Science.gov (United States)

    Stramaglia, Maria Elena

    2016-07-01

    The calibration of the ATLAS Pixel Detector at LHC fulfils two main purposes: to tune the front-end configuration parameters for establishing the best operational settings and to measure the tuning performance through a subset of scans. An analysis framework has been set up in order to take actions on the detector given the outcome of a calibration scan (e.g. to create a mask for disabling noisy pixels). The software framework to control all aspects of the Pixel Detector scans and analyses is called calibration console. The introduction of a new layer, equipped with new FE-I4 chips, required an update of the console architecture. It now handles scans and scan analyses applied together to chips with different characteristics. An overview of the newly developed calibration analysis software will be presented, together with some preliminary results.

  8. Design methodology: edgeless 3D ASICs with complex in-pixel processing for pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Fahim Farah, Fahim Farah [Northwestern U. (main); Deptuch, Grzegorz W. [Fermilab; Hoff, James R. [Fermilab; Mohseni, Hooman [Northwestern U. (main)

    2015-08-28

    The design methodology for the development of 3D integrated edgeless pixel detectors with in-pixel processing using Electronic Design Automation (EDA) tools is presented. A large area 3 tier 3D detector with one sensor layer and two ASIC layers containing one analog and one digital tier, is built for x-ray photon time of arrival measurement and imaging. A full custom analog pixel is 65μm x 65μm. It is connected to a sensor pixel of the same size on one side, and on the other side it has approximately 40 connections to the digital pixel. A 32 x 32 edgeless array without any peripheral functional blocks constitutes a sub-chip. The sub-chip is an indivisible unit, which is further arranged in a 6 x 6 array to create the entire 1.248cm x 1.248cm ASIC. Each chip has 720 bump-bond I/O connections, on the back of the digital tier to the ceramic PCB. All the analog tier power and biasing is conveyed through the digital tier from the PCB. The assembly has no peripheral functional blocks, and hence the active area extends to the edge of the detector. This was achieved by using a few flavors of almost identical analog pixels (minimal variation in layout) to allow for peripheral biasing blocks to be placed within pixels. The 1024 pixels within a digital sub-chip array have a variety of full custom, semi-custom and automated timing driven functional blocks placed together. The methodology uses a modified mixed-mode on-top digital implementation flow to not only harness the tool efficiency for timing and floor-planning but also to maintain designer control over compact parasitically aware layout. The methodology uses the Cadence design platform, however it is not limited to this tool.

  9. A prototype hybrid pixel detector ASIC for the CLIC experiment

    CERN Document Server

    Valerio, P; Arfaoui, S; Ballabriga, R; Benoit, M; Bonacini, S; Campbell, M; Dannheim, D; De Gaspari, M; Felici, D; Kulis, S; Llopart, X; Nascetti, A; Poikela, T; Wong, W S

    2014-01-01

    A prototype hybrid pixel detector ASIC specifically designed to the requirements of the vertex detector for CLIC is described and first electrical measurements are presented. The chip has been designed using a commercial 65 nm CMOS technology and comprises a matrix of 64x64 square pixels with 25 μm pitch. The main features include simultaneous 4-bit measure- ment of Time-over-Threshold (ToT) and Time-of-Arrival (ToA) with 10 ns accuracy, on-chip data compression and power pulsing capability.

  10. The phase-1 upgrade of the CMS pixel detector

    CERN Document Server

    Weber, Hannsjorg Artur

    2016-01-01

    The pixel detector of the CMS experiment will be upgraded during the extended end of year shutdown during winter 2016/2017. The upgraded detector will operate at full efficiency at an instantaneous luminosity of ${2\\times10^{34}}$\\,cm$^{{-2}}$s$^{{-1}}$ with increased detector acceptance and additional redundancy for the tracking, while at the same time reducing the material budget. The design and technological choices will be reviewed, and the status of the construction of the detector and the performance of its components as measured in system tests are discussed.

  11. Construction of the Phase I Forward Pixel Detector

    Science.gov (United States)

    Neylon, Ashton; Bartek, Rachel

    2017-01-01

    The silicon pixel detector is the innermost component of the CMS tracking system, providing high precision space point measurements of charged particle trajectories. The original CMS detector was designed for the nominal instantaneous LHC luminosity of 1 x 1034 cm-2s-1 . The LHC has already started to exceed this luminosity causing the CMS pixel detector to see a dynamic inefficiency caused by data losses due to buffer overflows. For this reason the CMS Collaboration has been building an upgraded pixel detector which is scheduled for installation during an extended year end technical stop during winter 2016/2017. The phase 1 upgrade includes four barrel layers and three forward disks, providing robust tracking and vertexing for LHC luminosities up to 2 x 1034 cm-2s-1 . The upgrade incorporates new readout chips, front-end electronics, DC-DC powering, and dual-phase CO2 cooling to achieve performance exceeding that of the present detector with a lower material budget. This contribution will review the design and technology choices of the Phase I detector and discuss the status of the detector. The challenges and difficulties encountered during the construction will also be presented, as well as the lessons learned for future upgrades. National Science Foundation.

  12. Study of electrode pattern design for a CZT-based PET detector.

    Science.gov (United States)

    Gu, Y; Levin, C S

    2014-06-07

    We are developing a 1 mm resolution small animal positron emission tomography (PET) system using 3D positioning cadmium zinc telluride photon detectors comprising 40 mm × 40 mm × 5 mm crystals metalized with a cross-strip electrode pattern with a 1 mm anode strip pitch. We optimized the electrode pattern design for intrinsic sensitivity and spatial, energy and time resolution performance using a test detector comprising cathode and steering electrode strips of varying dimensions. The study found 3 and 5 mm width cathode strips locate charge-shared photon interactions near cathode strip boundaries with equal precision. 3 mm width cathode strips exhibited large time resolution variability as a function of photon interaction location between the anode and cathode planes (~26 to ~127.5 ns full width at half maximum (FWHM) for 0.5 mm and 4.2 mm depths, respectively). 5 mm width cathode strips by contrast exhibited more stable time resolution for the same interaction locations (~34 to ~83 ns FWHM), provided more linear spatial positioning in the direction orthogonal to the electrode planes, and as much as 68.4% improvement in photon sensitivity over the 3 mm wide cathode strips. The results were understood by analyzing the cathode strips' weighting functions, which indicated a stronger 'small pixel' effect in the 3 mm wide cathode strips. Photon sensitivity and anode energy resolution were seen to improve with decreasing steering electrode bias from 0 to -80 V w.r.t. the anode potential. A slight improvement in energy resolution was seen for wider steering electrode strips (400 versus 100 µm) for charge-shared photon interactions. Although this study successfully focused on electrode pattern features for PET performance, the results are generally applicable to semiconductor photon detectors employing cross-trip electrode patterns.

  13. Phase 1 upgrade of the CMS pixel detector

    Science.gov (United States)

    Saha, Anirban

    2017-02-01

    The pixel tracker of the Compact Muon Solenoid (CMS) experiment is the innermost sub-detector, located close to the collision point, and is used for reconstruction of the tracks and vertices of charged particles. The present pixel detector was designed to work efficiently with the maximum instantaneous luminosity of 1 × 1034 cm‑2 s‑1. In 2017 the Large Hadron Collider (LHC) is expected to deliver a peak luminosity reaching up to 2 × 1034 cm‑2 s‑1, increasing the mean number of primary vertices to 50. Due to the radiation damage and significant data losses due to high occupancy in the readout chip of the pixel detector, the present system must be replaced by a new one in an extended end-of-year shutdown during winter 2016/2017 in order to maintain the excellent tracking and other physics performances. The main new features of the upgraded pixel detector are a ultra-light mechanical design with four barrel layers and three end-cap disks, digital readout chip with higher rate capability and a new cooling system. In this document, we discuss the motivations for the upgrade, the design, and technological choices made, the status of the construction of the new detector and the future plans for the installation and commissioning.

  14. CZT DTRA final report

    Energy Technology Data Exchange (ETDEWEB)

    Voss, L. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-02-01

    The objective of the project is to understand the physical origin of electronic noise injected by the electrical contacts in CZT and CdTe, and moreover to understand how it impacts the current- voltage (IV) relationships of these materials. This understanding is critical to enabling the next crucial enhancement in the performance of CZT radiation detectors, as there have recently been impressive advancements in the growth of CZT crystals, particularly at our commercial partner Redlen Technologies. Redlen scientists have successfully reduced the size of the transport-inhibiting tellurium precipitates to be <3 micrometers, such that, with sufficiently high fields, it is possible to achieve resolution of <1% at 662 keV using suitable electrode geometries. In contrast to the excellent progress in crystal growth, practitioners in the field of radiation detection have been fabricating rather routine contacts on CZT for nearly two decades; there is no basic understanding of the semiconductor physics of the contacts, and consequently no breakthrough progress in this area. Our objective is to resolve this inadequacy in CZT diode fabrication on the basis of a science-based study, such that CZT detectors can achieve their full promise in performance as superior contacts will enable use of higher fields with lower leakage current – thereby enhancing the resolution that is possible while eliminating the well-known “tailing” effect suffered by the photopeak. Our approach is to develop methods that reduce or eliminate leakage currents in CZT devices through “engineering” the surfaces with novel treatments and structures. This includes using high density plasma etching, doping via ion implantation and metal diffusion, rapid thermal annealing, amorphous semiconductor and dielectric films, and controlled oxide growth. Using these methods, sources of injected and generated noise at the surface can be eliminated via plasma etching and film deposition or oxide growth, while

  15. Novel integrated CMOS pixel structures for vertex detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kleinfelder, Stuart; Bieser, Fred; Chen, Yandong; Gareus, Robin; Matis, Howard S.; Oldenburg, Markus; Retiere, Fabrice; Ritter, Hans Georg; Wieman, Howard H.; Yamamoto, Eugene

    2003-10-29

    Novel CMOS active pixel structures for vertex detector applications have been designed and tested. The overriding goal of this work is to increase the signal to noise ratio of the sensors and readout circuits. A large-area native epitaxial silicon photogate was designed with the aim of increasing the charge collected per struck pixel and to reduce charge diffusion to neighboring pixels. The photogate then transfers the charge to a low capacitance readout node to maintain a high charge to voltage conversion gain. Two techniques for noise reduction are also presented. The first is a per-pixel kT/C noise reduction circuit that produces results similar to traditional correlated double sampling (CDS). It has the advantage of requiring only one read, as compared to two for CDS, and no external storage or subtraction is needed. The technique reduced input-referred temporal noise by a factor of 2.5, to 12.8 e{sup -}. Finally, a column-level active reset technique is explored that suppresses kT/C noise during pixel reset. In tests, noise was reduced by a factor of 7.6 times, to an estimated 5.1 e{sup -} input-referred noise. The technique also dramatically reduces fixed pattern (pedestal) noise, by up to a factor of 21 in our tests. The latter feature may possibly reduce pixel-by-pixel pedestal differences to levels low enough to permit sparse data scan without per-pixel offset corrections.

  16. Readout chip for the CMS pixel detector upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Rossini, Marco, E-mail: marco.rossini@phys.ethz.ch

    2014-11-21

    For the CMS experiment a new pixel detector is planned for installation during the extended shutdown in winter 2016/2017. Among the changes of the detector modified front end electronics will be used for higher efficiency at peak luminosity of the LHC and faster readout. The first prototype versions of the new readout chip have been designed and produced. The results of qualification and calibration for the new chip are presented in this paper.

  17. A reference voltage in capacitor-resister hybrid SAR ADC for front-end readout system of CZT detector

    Science.gov (United States)

    Wei, Liu; Tingcun, Wei; Bo, Li; Lifeng, Yang; Yongcai, Hu

    2016-01-01

    An on-chip reference voltage has been designed in capacitor-resister hybrid SAR ADC for CZT detector with the TSMC 0.35 μm 2P4M CMOS process. The voltage reference has a dynamic load since using variable capacitors and resistances, which need a large driving ability to deal with the current related to the time and sampling rate. Most of the previous articles about the reference for ADC present only the bandgap part for a low temperature coefficient and high PSRR. However, it is not enough and overall, it needs to consider the output driving ability. The proposed voltage reference is realized by the band-gap reference, voltage generator and output buffer. Apart from a low temperature coefficient and high PSRR, it has the features of a large driving ability and low power consumption. What is more, for CZT detectors application in space, a radiation-hardened design has been considered. The measurement results show that the output reference voltage of the buffer is 4.096 V. When the temperature varied from 0 to 80 °C, the temperature coefficient is 12.2 ppm/°C. The PSRR was -70 dB @ 100 kHz. The drive current of the reference can reach up to 10 mA. The area of the voltage reference in the SAR ADC chip is only 449 × 614 μm2. The total power consumption is only 1.092 mW. Project supported by the National Key Scientific Instrument and Equipment Development Project (No. 2011YQ040082), the National Natural Science Foundation of China (No. 61376034), and the Shaanxi Province Science and Technology Innovation Project (No. 2015KTZDGY03-03).

  18. Design Methodology: ASICs with complex in-pixel processing for Pixel Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Fahim, Farah [Fermilab

    2014-10-31

    The development of Application Specific Integrated Circuits (ASIC) for pixel detectors with complex in-pixel processing using Computer Aided Design (CAD) tools that are, themselves, mainly developed for the design of conventional digital circuits requires a specialized approach. Mixed signal pixels often require parasitically aware detailed analog front-ends and extremely compact digital back-ends with more than 1000 transistors in small areas below 100μm x 100μm. These pixels are tiled to create large arrays, which have the same clock distribution and data readout speed constraints as in, for example, micro-processors. The methodology uses a modified mixed-mode on-top digital implementation flow to not only harness the tool efficiency for timing and floor-planning but also to maintain designer control over compact parasitically aware layout.

  19. Silicon Sensors for the Upgrades of the CMS Pixel Detector

    CERN Document Server

    Centis Vignali, Matteo; Schleper, Peter

    2015-01-01

    The Compact Muon Solenoid (CMS) is a general purpose detector at the Large Hadron Collider (LHC). The LHC luminosity is constantly increased through upgrades of the accel- erator and its injection chain. Two major upgrades will take place in the next years. The rst upgrade involves the LHC injector chain and allows the collider to achieve a luminosity of about 2 10 34 cm-2 s-1 A further upgrade of the LHC foreseen for 2025 will boost its luminosity to 5 10 34 cm-2 s1. As a consequence of the increased luminosity, the detectors need to be upgraded. In particular, the CMS pixel detector will undergo two upgrades in the next years. The rst upgrade (phase I) consists in the substitution of the current pixel detector in winter 2016/2017. The upgraded pixel detector will implement new readout elec- tronics that allow ecient data taking up to a luminosity of 2 10 34 cm-2s-1,twice as much as the LHC design luminosity. The modules that will constitute the upgraded detector are being produced at dierent institutes. Ham...

  20. Monitoring Radiation Damage in the ATLAS Pixel Detector

    CERN Document Server

    Schorlemmer, André Lukas; Große-Knetter, Jörn; Rembser, Christoph; Di Girolamo, Beniamino

    2014-11-05

    Radiation hardness is one of the most important features of the ATLAS pixel detector in order to ensure a good performance and a long lifetime. Monitoring of radiation damage is crucial in order to assess and predict the expected performance of the detector. Key values for the assessment of radiation damage in silicon, such as the depletion voltage and depletion depth in the sensors, are measured on a regular basis during operations. This thesis summarises the monitoring program that is conducted in order to assess the impact of radiation damage and compares it to model predictions. In addition, the physics performance of the ATLAS detector highly depends on the amount of disabled modules in the ATLAS pixel detector. A worrying amount of module failures was observed during run I. Thus it was decided to recover repairable modules during the long shutdown (LS1) by extracting the pixel detector. The impact of the module repairs and module failures on the detector performance is analysed in this thesis.

  1. Modeling radiation damage to pixel sensors in the ATLAS detector

    CERN Document Server

    Ducourthial, Audrey; The ATLAS collaboration

    2017-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of $10^{15}n_{eq}/cm^2$ and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside ...

  2. ATLAS Pixel Detector Design For HL-LHC

    CERN Document Server

    Smart, Ben; The ATLAS collaboration

    2016-01-01

    The ATLAS Inner Detector will be replaced for the High-Luminosity LHC (HL-LHC) running in 2026. The new Inner Detector will be called the Inner Tracker (ITk). The ITk will cover an extended eta-range: at least to |eta|<3.2, and likely up to |eta|<4.0. The ITk will be an all-Silicon based detector, consisting of a Silicon strip detector outside of a radius of 362mm, and a Silicon pixel detector inside of this radius. Several novel designs are being considered for the ITk pixel detector, to cope with high-eta charged particle tracks. These designs are grouped into 'extended' and 'inclined' design-types. Extended designs have long pixel staves with sensors parallel to the beamline. High-eta particles will therefore hit these sensors at shallow angles, leaving elongated charge clusters. The length of such a charge cluster can be used to estimate the angle of the passing particle. This information can then be used in track reconstruction to improve tracking efficiency and reduce fake rates. Inclined designs ...

  3. ATLAS Pixel Detector Design For HL-LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00237541; The ATLAS collaboration

    2016-01-01

    The ATLAS Inner Detector will be replaced for the High-Luminosity LHC (HL-LHC) running in 2026. The new Inner Detector will be called the Inner Tracker (ITk). The ITk will cover an extended eta-range: at least to |eta|<3.2, and likely up to |eta|<4.0. The ITk will be an all-Silicon based detector, consisting of a Silicon strip detector outside of a radius of 362 mm, and a Silicon pixel detector inside of this radius. Several novel designs are being considered for the ITk pixel detector, to cope with high-eta charged particle tracks. These designs are grouped into 'extended' and 'inclined' design-types. Extended designs have long pixel staves with sensors parallel to the beamline, while inclined designs have sensors angled such that they point towards the interaction point. The relative advantages and challenges of these two classes of designs will be examined in this paper, along with the mechanical solutions being considered. Thermal management, radiation-length mapping, and electrical services will al...

  4. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Ducourthial, Audrey; The ATLAS collaboration

    2017-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of $10^{15} n_{eq}/cm^2$ and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside...

  5. ATLAS pixel detector design for the HL-LHC

    Science.gov (United States)

    Smart, B.

    2017-02-01

    The ATLAS Inner Detector will be replaced for the High-Luminosity LHC (HL-LHC) running in 2026. The new Inner Detector is called the Inner Tracker (ITk). The ITk will cover an extended η-range: at least to |η|<3.2, and likely up to 0|η|<4.. The ITk will be an all-Silicon based detector, consisting of a Silicon strip detector outside of a radius of 362 mm, and a Silicon pixel detector inside of this radius. Several novel designs are being considered for the ITk pixel detector, to cope with high-eta charged particle tracks. These designs are grouped into `extended' and `inclined' design-types. Extended designs have long pixel staves with sensors parallel to the beamline, while inclined designs have sensors angled such that they point towards the interaction point. The relative advantages and challenges of these two classes of designs will be examined in this paper, along with the mechanical solutions being considered. Thermal management, radiation-length mapping, and electrical services will also be discussed.

  6. 3D electronics for hybrid pixel detectors – TWEPP-09

    CERN Document Server

    Godiot, S; Chantepie, B; Clémens, J C; Fei, R; Fleury, J; Fougeron, D; Garcia-Sciveres, M; Hemperek, T; Karagounis, M; Krueger, H; Mekkaoui, A; Pangaud, P; Rozanov, A; Wermes, N

    2009-01-01

    Future hybrid pixel detectors are asking for smaller pixels in order to improve spatial resolution and to deal with an increasing counting rate. Facing these requirements is foreseen to be done by microelectronics technology shrinking. However, this straightforward approach presents some disadvantages in term of performances and cost. New 3D technologies offer an alternative way with the advantage of technology mixing. For the upgrade of ATLAS pixel detector, a 3D conception of the read-out chip appeared as an interesting solution. Splitting the pixel functionalities into two separate levels will reduce pixel size and open the opportunity to take benefit of technology's mixing. Based on a previous prototype of the read-out chip FE-I4 (IBM 130nm), this paper presents the design of a hybrid pixel read-out chip using threedimensional Tezzaron-Chartered technology. In order to disentangle effects due to Chartered 130nm technology from effects involved by 3D architecture, a first translation of FEI4 prototype had ...

  7. KPIX a pixel detector imaging chip

    CERN Document Server

    Cadeddu, S; Caria, M

    2002-01-01

    We present a VLSI custom device, named KPIX, developed in a 0.6 mu m CMOS technology. The circuit is dedicated to readout solid-state detectors covering large areas (on the order of square centimetre) and featuring very small currents. KPIX integrates 1024 channels (current amplifiers) and 8 ADCs on a 15.5x4 mm sup 2 area. Both an analogue and digital readout are allowed, with a 10 bit amplitude resolution. Amplifiers are organized in 8 columns of 128 rows. When choosing the digital or the analogue readout, the complete set of channels can be read out in about 30 ms. The specific design of the amplification cells allows to measure very small input current levels, on the order of fractions of pico-ampere. Power consumption has also been kept at the level of 80 mu W per cell and 150 mW (peak value) in total. The specific chip architecture and geometry allow use of many KPIX circuits together in order to serve a large detector sensitive area. The KPIX structure is presented along with some measurements character...

  8. The effect of characteristic x-rays on the spatial and spectral resolution of a CZT-based detector for breast CT

    Science.gov (United States)

    Glick, Stephen J.; Didier, Clay S.

    2011-03-01

    In an effort to improve the early stage detection and diagnosis of breast cancer, a number of research groups have been investigating the use of x-ray computerized tomography (CT) systems dedicated for use in imaging the breast. Preliminary results suggest that dedicated breast CT systems can provide improved visualization of 3D breast tissue as compared to conventional mammography. However, current breast CT prototypes that are being investigated have limitations resulting in less than desirable spatial resolution, lesion contrast, and signal-to-noise (SNR) ratio. Another option is a CT breast imaging system that uses a cadmium zinc telluride (CZT) based detector operating in a photon counting mode. This paper uses a Monte Carlo simulation to evaluate the effect of characteristic x-rays on spatial and spectral resolution for a CZT detector used for breast CT. It is concluded that using CZT of 500-750 μm would not cause significant differences in spatial or spectral resolution, nor in stopping power as compared to using CZT with thickness 2-3 mm.

  9. The first bump-bonded pixel detectors on CVD diamond

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Palmieri, V.G.; Pan, L.S.; Peitz, A.; Pernicka, M.; Pirollo, S.; Polesello, P.; Pretzl, K.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Steuerer, J.; Stone, R.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W. E-mail: william@physics.utoronto.ca; Turchetta, R.; Vittone, E.; Wagner, A.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Zeuner, W.; Ziock, H.; Zoeller, M.; Charles, E.; Ciocio, A.; Dao, K.; Einsweiler, K.; Fasching, D.; Gilchriese, M.; Joshi, A.; Kleinfelder, S.; Milgrome, O.; Palaio, N.; Richardson, J.; Sinervo, P.; Zizka, G

    1999-11-01

    Diamond is a nearly ideal material for detecting ionising radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow it to be used in high radiation environments. These characteristics make diamond sensors particularly appealing for use in the next generation of pixel detectors. Over the last year, the RD42 collaboration has worked with several groups that have developed pixel readout electronics in order to optimise diamond sensors for bump-bonding. This effort resulted in an operational diamond pixel sensor that was tested in a pion beam. We demonstrate that greater than 98% of the channels were successfully bump-bonded and functioning. The device shows good overall hit efficiency as well as clear spatial hit correlation to tracks measured in a silicon reference telescope. A position resolution of 14.8 {mu}m was observed, consistent with expectations given the detector pitch.

  10. Performance of the INTPIX6 SOI pixel detector

    Science.gov (United States)

    Arai, Y.; Bugiel, Sz.; Dasgupta, R.; Idzik, M.; Kapusta, P.; Kucewicz, W.; Miyoshi, T.; Turala, M.

    2017-01-01

    Characterization of the monolithic pixel detector INPTIX6, designed at KEK and fabricated in Lapis 0.2 μ m Fully-Depleted, Low-Leakage Silicon-On-Insulator (SOI) CMOS technology, was performed. The INTPIX6 comprises a large area of 1408 × 896 integrating type squared pixels of 12 micron pitch. In this work the performance and measurement results of the prototypes produced on lower resistivity Czochralski type (CZ-n) and high resistivity floating zone (FZ-n) sensor wafers are presented. Using 241Am radioactive source the noise of INTPIX6 was measured, showing the ENC (Equivalent Noise Charge) of about 70 e-. The resolution calculated from the FWHM of the Iron-55 X-ray peak was about 100 e-. The radiation hardness of the SOI pixel detector was also investigated. The CZ-n type INTPIX6 received a dose of 60 krad and its performance has been continuously monitored during the irradiation.

  11. The ATLAS Insertable B-Layer Pixel Detector

    CERN Document Server

    Pernegger, H; The ATLAS collaboration

    2011-01-01

    ATLAS currently develops a new pixel detector for the first upgrade of its tracking system: The ATLAS Insertable B-Layer Pixel detector (IBL). The new layer will be inserted between the inner most layer of the current pixel detector and a new beam pipe. The sensors are placed at a radius of 3.4 cm. The expected high radiation levels and high hit occupancy require new developments for front-end chip and sensors which can stand radiation levels beyond 5$ imes$10$^{15}$ n$_{eq}$/cm$^{2}$ . ATLAS has developed the new FEI4 chip and new silicon sensors to be used as pixel modules. Furthermore a new lightweight support and cooling structure was developed, which minimizes the overall radiation length and allows detector cooling with CO$_{2}$ at -40 $^{circ}$C coolant temperature. Currently the overall integration and installation procedure is being developed and tested ready for installation in 2013. The paper summarizes the current state of development of IBL modules, first preliminary test results of the new chip ...

  12. Overview of the ATLAS Insertable B-Layer Pixel Detector

    CERN Document Server

    Pernegger, H; The ATLAS collaboration

    2011-01-01

    ATLAS currently develops a new pixel detector for the first upgrade of its tracking system: The ATLAS Insertable B-Layer Pixel detector (IBL). The new layer will be inserted between the inner most layer of the current pixel detector and a new beam pipe. The sensors are placed at a radius of 3.4cm. The expected high radiation levels and high hit occupancy require new developments for front-end chip and the sensor which can stand radiation levels beyond 5E15 neq/cm2. ATLAS has developed the new FEI4 and new silicon sensors to be used as pixel modules. Furthermore a new lightweight support and cooling structure was developed, which minimizes the overall radiation and allows detector cooling with CO2 at -40C coolant temperature. Currently the overall integration and installation procedure is being developed and test ready for installation in ATLAS in 2013. The presentation summarizes the current state of development of IBL modules, first preliminary test results of the new chip with new sensors, the construction ...

  13. Phase 1 upgrade of the CMS Pixel Detector

    CERN Document Server

    Saha, Anirban

    2016-01-01

    The pixel tracker of the Compact Muon Solenoid (CMS) experiment is the innermost sub-detector, located close to the collision point, and is used for reconstruction of the tracks and vertices of charged particles. The present pixel detector was designed to work efficiently with the maximum instantaneous luminosity of $\\rm 1 \\times 10^{34}$ cm$^{-2}$ s$^{-1}$. In 2017 the Large Hadron Collider (LHC) is expected to deliver a peak luminosity reaching up to $\\rm 2\\times10^{34} cm^{-2}s^{-1}$, increasing the mean number of primary vertices to 50. Due to the radiation damage and significant data losses due to high occupancy in the readout chip of the pixel detector, the present system must be replaced by a new one in an extended end-of-year shutdown during winter 2016/2017 in order to maintain the excellent tracking and other physics performances. The main new features of the upgraded pixel detector are the a ultra-light mechanical design with four barrel layers and three end-cap disks, digital readout chip with hi...

  14. Charge amplitude distribution of the Gossip gaseous pixel detector

    NARCIS (Netherlands)

    Blanco Carballo, V.M.; Chefdeville, M.A.; Colas, P.; Giomataris, Y.; van der Graaf, H.; Gromov, V.; Hartjes, F.; Kluit, R.; Koffeman, E.; Salm, Cora; Schmitz, Jurriaan; Smits, Sander M.; Timmermans, J.; Timmermans, J.; Visschers, J.L.

    2007-01-01

    The Gossip gaseous pixel detector is being developed for the detection of charged particles in extreme high radiation environments as foreseen close to the interaction point of the proposed super LHC. The detecting medium is a thin layer of gas. Because of the low density of this medium, only a few

  15. Electron imaging with Medipix2 hybrid pixel detector

    CERN Document Server

    McMullan, G; Chen, S; Henderson, R; Llopart, X; Summerfield, C; Tlustos, L; Faruqi, A R

    2007-01-01

    The electron imaging performance of Medipix2 is described. Medipix2 is a hybrid pixel detector composed of two layers. It has a sensor layer and a layer of readout electronics, in which each 55 μm×55 μm pixel has upper and lower energy discrimination and MHz rate counting. The sensor layer consists of a 300 μm slab of pixellated monolithic silicon and this is bonded to the readout chip. Experimental measurement of the detective quantum efficiency, DQE(0) at 120 keV shows that it can reach 85% independent of electron exposure, since the detector has zero noise, and the DQE(Nyquist) can reach 35% of that expected for a perfect detector (4/π2). Experimental measurement of the modulation transfer function (MTF) at Nyquist resolution for 120 keV electrons using a 60 keV lower energy threshold, yields a value that is 50% of that expected for a perfect detector (2/π). Finally, Monte Carlo simulations of electron tracks and energy deposited in adjacent pixels have been performed and used to calculate expected v...

  16. Pixel hybrid photon detectors for the ring imaging Cherenkov detectors of LHCb

    CERN Document Server

    Somerville, L

    2005-01-01

    A Pixel Hybrid Photon Detector (pixel HPD) has been developed for the LHCb Ring Imaging Cherenkov (RICH) detectors. The pixel HPD is a vacuum tube with a multi-alkali photocathode, high-voltage cross- focused electron optics and an anode consisting of a silicon pixel detector bump-bonded to a CMOS readout chip; the readout chip is thus fully encapsulated in the device. The pixel HPD fulfils the stringent requirements for the RICH detectors of LHCb, combining single photon sensitivity, high signal-to-noise ratio and fast readout with an ~8cm diameter active area and an effective pixel size of 2.5mm 2.5mm at the photocathode. The performance and characteristics of two prototype pixel HPDs have been studied in laboratory measurements and in recent beam tests. The results of all measurements agree with expectations and fulfil the LHCb RICH requirements. In readiness for production of the ~500pixel HPDs for the RICH detectors, a test programme was designed and implemented to ensure component quality control at eac...

  17. Optical Links for the ATLAS Pixel Detector

    CERN Document Server

    Gregor, Ingrid-Maria

    In der vorliegenden Dissertation wird eine strahlentolerante optische Datenstrecke mit hoher Datenrate für den Einsatz in dem Hochenergiephysikexperiment Atlas am Lhc Beschleuniger entwickelt. Da die Lhc-Experimente extremen Strahlenbelastungen ausgesetzt sind, müssen die Komponenten spezielle Ansprüche hinsichtlich der Strahlentoleranz erfüllen. Die Qualifikation der einzelnen Bauteile wurde im Rahmen dieser Arbeit durchgeführt. Die zu erwartenden Fluenzen im Atlas Inner Detector für Silizium und Gallium Arsenid (GaAs) wurden berechnet. Siliziumbauteile werden einer Fluenz von bis zu 1.1.1015neq /cm2 in 1 MeV äquivalenten Neutronen ausgesetzt sein, wohingegen GaAs Bauteile bis zu 7.8.1015neq /cm2 ausgesetzt sein werden. Die Strahlentoleranz der einzelnen benötigten Komponenten wie z.B. der Laserdioden sowie der jeweiligen Treiberchips wurde untersucht. Sowohl die Photo- als auch die Laserdioden haben sich als strahlentolerant für die Fluenzen an dem vorgesehenen Radius erwiesen. Aus de...

  18. An EUDET/AIDA Pixel Beam Telescope for Detector Development

    CERN Document Server

    Rubinskiy, I

    2015-01-01

    Ahigh resolution(σ< 2 μm) beam telescope based on monolithic active pixel sensors (MAPS) was developed within the EUDET collaboration. EUDET was a coordinated detector R&D programme for the future International Linear Collider providing test beam infrastructure to detector R&D groups. The telescope consists of six sensor planes with a pixel pitch of either 18.4 μm or 10 μmand canbe operated insidea solenoidal magnetic fieldofupto1.2T.Ageneral purpose cooling, positioning, data acquisition (DAQ) and offine data analysis tools are available for the users. The excellent resolution, readout rate andDAQintegration capabilities made the telescopea primary beam tests tool also for several CERN based experiments. In this report the performance of the final telescope is presented. The plans for an even more flexible telescope with three differentpixel technologies(ATLASPixel, Mimosa,Timepix) withinthenew European detector infrastructure project AIDA are presented.

  19. Compensation of radiation damages for SOI pixel detector via tunneling

    CERN Document Server

    Yamada, Miho; Kurachi, Ikuo

    2015-01-01

    We are developing monolithic pixel detectors based on SOI technology for high energy physics, X-ray applications and so on.To employ SOI pixel detector on such radiation environments, we have to solve effects of total ionization damages (TID) for transistors which are enclosed in oxide layer.The holes which are generated and trapped in the oxide layers after irradiation affect characteristics of near-by transistors due to its positive electric field.Annealing and radiation of ultraviolet are not realistic to remove trapped holes for a fabricated detector due to thermal resistance of components and difficulty of handling. We studied compensation of TID effects by tunneling using a high-voltage. For decrease of trapped holes, applied high-voltage to buried p-well which is under oxide layer to inject the electrons into the oxide layer.In this report, recent progress of this study is shown.

  20. Signal variations in high granularity Si pixel detectors

    CERN Document Server

    Tlustos, L; Heijne, Erik H M; Llopart-Cudie, Xavier

    2004-01-01

    Fixed pattern noise is one of the limiting factors of image quality and degrades the achievable spatial resolution. In the case of silicon sensors non-uniformities due to doping inhomogeneities can be limited by operating the sensor in strong overdepletion. For high granularity photon counting pixel detectors an additional high frequency interpixel signal variation is an important factor for the achievable signal to noise ratio (SNR). It is common practice to apply flatfield corrections to increase the SNR of the detector system. For the case of direct conversion detectors it can be shown that the Poisson limit can be reached for floodfield irradiation. However when used for imaging with spectral X-ray sources flatfield corrections are less effective. This is partly a consequence of charge sharing between adjacent pixels, which gives rise to an effective energy spectrum seen by the readout, which is different from the spectral content of the incident beam. In this paper we present simulations and measurements...

  1. Pixel detector system development at Diamond Light Source

    Science.gov (United States)

    Marchal, J.; Horswell, I.; Gimenez, E. N.; Tartoni, N.

    2010-10-01

    Hybrid pixel detectors consisting of an array of silicon photodiodes bump-bonded to CMOS read-out chips provide high signal-to-noise ratio and high dynamic range compared to CCD-based detectors and Image Plates. These detector features are important for SAXS experiments where a wide range of intensities are present in the images. For time resolved SAXS experiments, high frame rates are compulsory. The latest CMOS read-out chip developed by the MEDIPIX collaboration provides high frame rate and continuous acquisition mode. A read-out system for an array of MEDIPIX3 sensors is under development at Diamond Light Source. This system will support a full resolution frame rate of 1 kHz at a pixel counter depth of 12-bit and a frame rate of 30 kHz at a counter depth of 1 bit. Details concerning system design and MEDIPIX sensors characterization are presented.

  2. GaAs Medipix2 hybrid pixel detector

    CERN Document Server

    Kostamo, P; Vähänen, S; Tlustos, L; Fröjdh, C; Campbell, M; Zhilyaev, Y; Lipsanen, H

    2008-01-01

    A GaAs Medipix2 hybrid pixel detector based on high purity epitaxial GaAs material was successfully fabricated. The mesa type GaAs sensor with 256×256 pixels and total area of 1.4×1.4 cm2 was made of a 140-μm-thick epitaxial p–i–n structure utilizing reactive ion etching. A final thickness of approximately 110 μm for the all-epitaxial sensor element is achieved by back-thinning procedure. The sensor element is bump bonded to a Medipix2 read-out ASIC. The detector is capable of room temperature spectroscopic operation and it demonstrates the potential of GaAs for high resolution X-ray imaging systems operating at room temperature. This work describes the manufacturing process and electrical properties of the GaAs Medipix2 hybrid detector.

  3. Validation studies of the ATLAS pixel detector control system

    Energy Technology Data Exchange (ETDEWEB)

    Schultes, Joachim [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany)]. E-mail: schultes@physik.uni-wuppertal.de; Becks, Karl-Heinz [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany); Flick, Tobias [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany); Henss, Tobias [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany); Imhaeuser, Martin [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany); Kersten, Susanne [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany); Kind, Peter [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany); Lantzsch, Kerstin [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany); Maettig, Peter [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany); Reeves, Kendall [University of Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany); Weingarten, Jens [University of Bonn, Nussallee 12, 53115 Bonn (Germany)

    2006-09-01

    The ATLAS pixel detector consists of 1744 identical silicon pixel modules arranged in three barrel layers providing coverage for the central region, and three disk layers on either side of the primary interaction point providing coverage of the forward regions. Once deployed into the experiment, the detector will employ optical data transfer, with the requisite powering being provided by a complex system of commercial and custom-made power supplies. However, during normal performance and production tests in the laboratory, only single modules are operated and electrical readout is used. In addition, standard laboratory power supplies are used. In contrast to these normal tests, the data discussed here were obtained from a multi-module assembly which was powered and read out using production items: the optical data path, the final design power supply system using close to final services, and the Detector Control System (DCS)

  4. Comprehensive measurements of GaAs pixel detectors capacitance

    CERN Document Server

    Caria, M; D'Auria, S; Lai, A; Randaccio, P; Cadeddu, S

    2002-01-01

    We have studied GaAs pixel detectors on semi-insulating wafers with Schottky contacts. We performed comprehensive measurements on the inter-pixel and capacitance to back plane. Being semi-insulating, the behaviour is totally different with respect to other common semiconductors, such as high resistivity silicon. Non-homogeneities are also an issue, due to both the contacts and the crystal bulk. In order to detect them and their influence on capacitance, we undertook systematic measurements with different configurations of the measuring electrodes.

  5. Semiconductor micropattern pixel detectors a review of the beginnings

    CERN Document Server

    Heijne, Erik H M

    2001-01-01

    The innovation in monolithic and hybrid semiconductor 'micropattern' or 'reactive' pixel detectors for tracking in particle physics was actually to fit logic and pulse processing electronics with µW power on a pixel area of less than 0.04 mm2, retaining the characteristics of a traditional nuclear amplifier chain. The ns timing precision in conjunction with local memory and logic operations allowed event selection at > 10 MHz rates with unambiguous track reconstruction even at particle multiplicities > 10 cm-2. The noise in a channel was ~100 e- r.m.s. and enabled binary operation with random noise 'hits' at a level 30 Mrad, respectively.

  6. High frame rate measurements of semiconductor pixel detector readout IC

    Science.gov (United States)

    Szczygiel, R.; Grybos, P.; Maj, P.

    2012-07-01

    We report on high count rate and high frame rate measurements of a prototype IC named FPDR90, designed for readouts of hybrid pixel semiconductor detectors used for X-ray imaging applications. The FPDR90 is constructed in 90 nm CMOS technology and has dimensions of 4 mm×4 mm. Its main part is a matrix of 40×32 pixels with 100 μm×100 μm pixel size. The chip works in the single photon counting mode with two discriminators and two 16-bit ripple counters per pixel. The count rate per pixel depends on the effective CSA feedback resistance and can be set up to 6 Mcps. The FPDR90 can operate in the continuous readout mode, with zero dead time. Due to the architecture of digital blocks in pixel, one can select the number of bits read out from each counter from 1 to 16. Because in the FPDR90 prototype only one data output is available, the frame rate is 9 kfps and 72 kfps for 16 bits and 1 bit readout, respectively (with nominal clock frequency of 200 MHz).

  7. High frame rate measurements of semiconductor pixel detector readout IC

    Energy Technology Data Exchange (ETDEWEB)

    Szczygiel, R., E-mail: robert.szczygiel@agh.edu.pl [AGH University of Science and Technology, Department of Measurement and Instrumentation, Al. Mickiewicza 30, 30-059 Cracow (Poland); Grybos, P.; Maj, P. [AGH University of Science and Technology, Department of Measurement and Instrumentation, Al. Mickiewicza 30, 30-059 Cracow (Poland)

    2012-07-11

    We report on high count rate and high frame rate measurements of a prototype IC named FPDR90, designed for readouts of hybrid pixel semiconductor detectors used for X-ray imaging applications. The FPDR90 is constructed in 90 nm CMOS technology and has dimensions of 4 mm Multiplication-Sign 4 mm. Its main part is a matrix of 40 Multiplication-Sign 32 pixels with 100 {mu}m Multiplication-Sign 100 {mu}m pixel size. The chip works in the single photon counting mode with two discriminators and two 16-bit ripple counters per pixel. The count rate per pixel depends on the effective CSA feedback resistance and can be set up to 6 Mcps. The FPDR90 can operate in the continuous readout mode, with zero dead time. Due to the architecture of digital blocks in pixel, one can select the number of bits read out from each counter from 1 to 16. Because in the FPDR90 prototype only one data output is available, the frame rate is 9 kfps and 72 kfps for 16 bits and 1 bit readout, respectively (with nominal clock frequency of 200 MHz).

  8. Physics benchmarks for the Belle II pixel detector

    Science.gov (United States)

    Li Gioi, L.

    2015-03-01

    SuperKEKB, the massive upgrade of the asymmetric electron positron collider KEKB in Tsukuba, Japan, aims at an integrated luminosity in excess of 50 ab-1. It will deliver an instantaneous luminosity of 8 ṡ 1035 cm-2s-1, which is 40 times higher than the world record set by KEKB. At this high luminosity, a large increase of the background relative to the previous KEKB machine is expected. This and the more demanding physics rate ask for an entirely new tracking system. The expected increase of background would in fact create an unacceptable high occupancy for a silicon strip detector, making an efficient tracks reconstruction and vertexing impossible. The solution for Belle II is a pixel detector which intrinsically provides three dimensional space points. The new two layers silicon pixel vertex detector, based on DEPFET technology, will be mounted directly on the beam pipe. It will provide an accurate measurement of the tracks position in order to precisely reconstruct the decay vertex of the short living particles.In this paper we will discuss the physics performance of the Belle II pixel vertex detector which will be essential for the precise measurement of the CP parameters in various B and D decay modes.

  9. Simulation and measurement of pulse height and rise-time for electron signals in CZT detectors:. influence of material and electronics parameters

    Science.gov (United States)

    Mathy, F.; Bonnefoy, J. P.; Gliere, A.; Mestais, C.; Verger, L.

    2001-02-01

    A model for simulation of amplitude vs. rise-time biparametric spectra as a function of CZT materials properties was developed. This model takes into account the physical properties of the CZT detectors, the electric field profile and the physics of γ- ray interaction with CZT. The model has been refined to include the filtering effects of the front-end electronics and applied again to biparametric spectra. The electronic filtering is represented by a combination of linear band pass filters. The rise-time measurement circuit induces a non-linearity that is taken into account. A comparison between the electronics simulations and calibration measurements on the actual circuits is presented. In addition, physical and electrical properties of several CZT samples have been characterized and these properties have been incorporated in the model so that actual and simulated biparametric spectra can be compared. Finally, the model is applied to show the influence of the main physical parameters (mobility and lifetime) and of the applied electric field on the biparametric spectra.

  10. MTF study of planar small pixel pitch quantum IR detectors

    Science.gov (United States)

    Gravrand, O.; Baier, N.; Ferron, A.; Rochette, F.; Berthoz, J.; Rubaldo, L.; Cluzel, R.

    2014-06-01

    The actual trend in quantum IR detector development is the design of very small pixel pitch large arrays. From previously 30μm pitch, the standard pixel pitch is today 15μm and is expected to decrease to 12μm in the next few years. Furthermore, focal plane arrays (FPA) with pixel pitch as small as small as 10μm has been demonstrated. Such ultra-small pixel pitches are very small compared to the typical length ruling the electrical characteristics of the absorbing materials, namely the minority carrier diffusion length. As an example for low doped N type HgCdTe or InSb material, this diffusion length is of the order of 30 to 50μm, i.e. 3 to 5 times the targeted pixel pitches. This has strong consequences on the modulation transfer function (MTF) for planar structures, where the lateral extension of the photodiode is limited by diffusion. For such aspect ratios, the self-confinement of neighboring diodes may not be efficient enough to maintain optimal MTF. Therefore, this issue has to be addressed in order to take full benefits of the pixel pitch reduction in terms of image resolution. This paper aims at investigating the MTF evolution of HgCdTe and InSb FPAs decreasing the pixel pitch below 15μm. Both experimental measurements and finite element simulations are used to discuss this issue. Different scenarii will be compared, namely deep mesa etch between pixels, internal drift, surface recombination, thin absorbing layers.

  11. Comparison of a pixelated semiconductor detector and a non-pixelated scintillation detector in pinhole SPECT system for small animal study.

    Science.gov (United States)

    Iida, Hirokazu; Ogawa, Koichi

    2011-02-01

    The aim of this work was to evaluate a pixelated semiconductor detector and non-pixelated scintillation detector in a pinhole SPECT system for small animal imaging. We assumed two pixelated CdTe semiconductor detectors (a monolithic type and a modular type) and two non-pixelated NaI(Tl) scintillation detectors (a conventional type and a large detector field type). For the monolithic semiconductor detector we assumed that the size of a pixel was 1.0 × 1.0 mm², the thickness 1 mm, and an effective detector field 128 × 128 mm². For the modular-type semiconductor detector we assumed that the size of a pixel was 2.5 × 2.5 mm², the thickness 5 mm, and an effective detector field 320 × 320 mm². For the two scintillation detectors we assumed that the size of a pixel was 1.4 × 1.4 mm² and the intrinsic spatial resolution 4.0 mm FWHM, and the thickness 9 mm. For the conventional scintillation detector we assumed that the effective detector field was 179.2 × 179.2 mm², and for the large field scintillation detector 358.2 × 358.2 mm² and the magnification factor two. In the simulation we used a pinhole collimator with a pinhole size of 0.3 mm. We reconstructed SPECT images of hot-rod and cold-channel phantoms with projection data calculated with a Monte Carlo method assuming a fixed data acquisition time, and evaluated the image quality with respect to contrast and spatial resolution. In addition, we calculated the scatter fraction to compare the amount of scattered photons between the pixelated and non-pixelated detectors. The image quality of the modular-type pixelated detector was similar to that of the non-pixelated detector operated with a twofold magnified data acquisition. The scattered photons and the parallax effect in the pixelated detector were small and similar to those in the non-pixelated detector. The performance of a modular-type pixelated semiconductor detector was almost the same as that of a non-pixelated scintillation detector with a magnified

  12. CMS Pixel Detector design for HL-LHC

    CERN Document Server

    Migliore, Ernesto

    2016-01-01

    The LHC machine is planning an upgrade program which will smoothly bring the luminosity to about 7.5$\\times$10$^{34}$cm$^{-2}$s$^{-1}$ in 2028, to possibly reach an integrated luminosity of 3000 fb$^{-1}$ by the end of 2037. This High Luminosity scenario, HL-LHC, will present new challenges in higher data rates and increased radiation.In order to maintain its physics reach the CMS Collaboration has undertaken a preparation program of the detector known as Phase-2 upgrade. The CMS Phase-2 Pixel upgrade will require a high bandwidth readout system and high radiation tolerance for sensors and on-detector ASICs. Several technologies for the upgrade sensors are being studied. Serial powering schemes are under consideration to accommodate significant constraints on the system. These prospective designs, as well as new layout geometries that include very forward pixel discs, will be presented together with performance estimations.

  13. Optimisation of ROB mapping for SCT and Pixel detectors

    CERN Document Server

    Wheeler, S

    1999-01-01

    A simple object-oriented program has been written to simulate the SCT and Pixel detectors in order to determine the suitability of various ROB mapping schemes in the context of the Level 2 trigger. Layer and tower mappings have been investigated separately for the SCT barrel and endcap and for the Pixel barrel and endcap. Events containing one RoI were fired at each detector part and the number of ROBs hit determined. As a result, plots of ROB output data rates and ROB hit frequency as a function of ROB ID were obtained. In general it was found that layer mapping schemes might result in unacceptably high data rates and frequencies. This result would have to be confirmed with more detailed modelling. The tower mappings investigated, in general produced acceptable rates.

  14. The ALICE Silicon Pixel Detector Control and Calibration Systems

    CERN Document Server

    Calì, Ivan Amos; Manzari, Vito; Stefanini, Giorgio

    2008-01-01

    The work presented in this thesis was carried out in the Silicon Pixel Detector (SPD) group of the ALICE experiment at the Large Hadron Collider (LHC). The SPD is the innermost part (two cylindrical layers of silicon pixel detec- tors) of the ALICE Inner Tracking System (ITS). During the last three years I have been strongly involved in the SPD hardware and software development, construction and commissioning. This thesis is focused on the design, development and commissioning of the SPD Control and Calibration Systems. I started this project from scratch. After a prototyping phase now a stable version of the control and calibration systems is operative. These systems allowed the detector sectors and half-barrels test, integration and commissioning as well as the SPD commissioning in the experiment. The integration of the systems with the ALICE Experiment Control System (ECS), DAQ and Trigger system has been accomplished and the SPD participated in the experimental December 2007 commissioning run. The complex...

  15. CMS Pixel Detector design for HL-LHC

    Science.gov (United States)

    Migliore, E.

    2016-12-01

    The LHC machine is planning an upgrade program which will smoothly bring the luminosity to about 7.5×1034cm-2s-1 in 2028, to possibly reach an integrated luminosity of 3000 fb-1 by the end of 2037. This High Luminosity scenario, HL-LHC, will present new challenges in higher data rates and increased radiation. In order to maintain its physics reach the CMS collaboration has undertaken a preparation program of the detector known as Phase-2 upgrade. The CMS Phase-2 Pixel upgrade will require a high bandwidth readout system and high radiation tolerance for sensors and on-detector ASICs. Several technologies for the upgrade sensors are being studied. Serial powering schemes are under consideration to accommodate significant constraints on the system. These prospective designs, as well as new layout geometries that include very forward pixel discs, will be presented together with performance estimation.

  16. Monolithic active pixel radiation detector with shielding techniques

    Energy Technology Data Exchange (ETDEWEB)

    Deptuch, Grzegorz W.

    2016-09-06

    A monolithic active pixel radiation detector including a method of fabricating thereof. The disclosed radiation detector can include a substrate comprising a silicon layer upon which electronics are configured. A plurality of channels can be formed on the silicon layer, wherein the plurality of channels are connected to sources of signals located in a bulk part of the substrate, and wherein the signals flow through electrically conducting vias established in an isolation oxide on the substrate. One or more nested wells can be configured from the substrate, wherein the nested wells assist in collecting charge carriers released in interaction with radiation and wherein the nested wells further separate the electronics from the sensing portion of the detector substrate. The detector can also be configured according to a thick SOA method of fabrication.

  17. Monolithic active pixel radiation detector with shielding techniques

    Science.gov (United States)

    Deptuch, Grzegorz W.

    2016-09-06

    A monolithic active pixel radiation detector including a method of fabricating thereof. The disclosed radiation detector can include a substrate comprising a silicon layer upon which electronics are configured. A plurality of channels can be formed on the silicon layer, wherein the plurality of channels are connected to sources of signals located in a bulk part of the substrate, and wherein the signals flow through electrically conducting vias established in an isolation oxide on the substrate. One or more nested wells can be configured from the substrate, wherein the nested wells assist in collecting charge carriers released in interaction with radiation and wherein the nested wells further separate the electronics from the sensing portion of the detector substrate. The detector can also be configured according to a thick SOA method of fabrication.

  18. Descent of the Silicon Pixel Detector (SPD) for ALICE Experiment

    CERN Multimedia

    2007-01-01

    The Silicon Pixel Detector (SPD) constitutes the two innermost layers of the ALICE Inner Tracking System (ITS) at radii of 3.9 cm and 7.6 cm, respectively. It is a fundamental element for the determination of the position of the primary vertex as well as for the measurement of the impact parameter of secondary tracks originating from the weak decays of strange, charm and beauty particles.

  19. Performance comparison of small-pixel CdZnTe radiation detectors with gold contacts formed by sputter and electroless deposition

    Science.gov (United States)

    Bell, S. J.; Baker, M. A.; Duarte, D. D.; Schneider, A.; Seller, P.; Sellin, P. J.; Veale, M. C.; Wilson, M. D.

    2017-06-01

    Recent improvements in the growth of wide-bandgap semiconductors, such as cadmium zinc telluride (CdZnTe or CZT), has enabled spectroscopic X/γ-ray imaging detectors to be developed. These detectors have applications covering homeland security, industrial analysis, space science and medical imaging. At the Rutherford Appleton Laboratory (RAL) a promising range of spectroscopic, position sensitive, small-pixel Cd(Zn)Te detectors have been developed. The challenge now is to improve the quality of metal contacts on CdZnTe in order to meet the demanding energy and spatial resolution requirements of these applications. The choice of metal deposition method and fabrication process are of fundamental importance. Presented is a comparison of two CdZnTe detectors with contacts formed by sputter and electroless deposition. The detectors were fabricated with a 74 × 74 array of 200 μm pixels on a 250 μm pitch and bump-bonded to the HEXITEC ASIC. The X/γ-ray emissions from an 241Am source were measured to form energy spectra for comparison. It was found that the detector with contacts formed by electroless deposition produced the best uniformity and energy resolution; the best pixel produced a FWHM of 560 eV at 59.54 keV and 50% of pixels produced a FWHM better than 1.7 keV . This compared with a FWHM of 1.5 keV for the best pixel and 50% of pixels better than 4.4 keV for the detector with sputtered contacts.

  20. Pixel diamond detectors for excimer laser beam diagnostics

    Science.gov (United States)

    Girolami, M.; Allegrini, P.; Conte, G.; Salvatori, S.

    2011-05-01

    Laser beam profiling technology in the UV spectrum of light is evolving with the increase of excimer lasers and lamps applications, that span from lithography for VLSI circuits to eye surgery. The development of a beam-profiler, able to capture the excimer laser single pulse and process the acquired pixel current signals in the time period between each pulse, is mandatory for such applications. 1D and 2D array detectors have been realized on polycrystalline CVD diamond specimens. The fast diamond photoresponse, in the ns time regime, suggests the suitability of such devices for fine tuning feedback of high-power pulsed-laser cavities, whereas solar-blindness guarantees high performance in UV beam diagnostics, also under high intensity background illumination. Offering unique properties in terms of thermal conductivity and visible-light transparency, diamond represents one of the most suitable candidate for the detection of high-power UV laser emission. The relatively high resistivity of diamond in the dark has allowed the fabrication of photoconductive vertical pixel-detectors. A semitransparent light-receiving back-side contact has been used for detector biasing. Each pixel signal has been conditioned by a multi-channel read-out electronics made up of a high-sensitive integrator and a Σ-Δ A/D converter. The 500 μs conversion time has allowed a data acquisition rate up to 2 kSPS (Sample Per Second).

  1. Small-Scale Readout Systems Prototype for the STAR PIXEL Detector

    Energy Technology Data Exchange (ETDEWEB)

    Szelezniak, Michal A.; Besson, Auguste; Colledani, Claude; Dorokhov, Andrei; Dulinski, Wojciech; Greiner, Leo C.; Himmi, Abdelkader; Hu, Christine; Matis, Howard S.; Ritter, Hans Georg; Rose, Andrew; Shabetai, Alexandre; Stezelberger, Thorsten; Sun, Xiangming; Thomas, Jim H.; Valin, Isabelle; Vu, Chinh Q.; Wieman, Howard H.; Winter, Marc

    2008-10-01

    A prototype readout system for the STAR PIXEL detector in the Heavy Flavor Tracker (HFT) vertex detector upgrade is presented. The PIXEL detector is a Monolithic Active Pixel Sensor (MAPS) based silicon pixel vertex detector fabricated in a commercial CMOS process that integrates the detector and front-end electronics layers in one silicon die. Two generations ofMAPS prototypes designed specifically for the PIXEL are discussed. We have constructed a prototype telescope system consisting of three small MAPS sensors arranged in three parallel and coaxial planes with a readout system based on the readout architecture for PIXEL. This proposed readout architecture is simple and scales to the size required to readout the final detector. The real-time hit finding algorithm necessary for data rate reduction in the 400 million pixel detector is described, and aspects of the PIXEL system integration into the existing STAR framework are addressed. The complete system has been recently tested and shown to be fully functional.

  2. Pixel hybrid photon detector magnetic distortions characterization and compensation

    CERN Document Server

    Aglieri-Rinella, G; D'Ambrosio, Carmelo; Forty, Roger W; Gys, Thierry; Patel, Mitesh; Piedigrossi, Didier; Van Lysebetten, Ann

    2004-01-01

    The LHCb experiment requires positive kaon identification in the momentum range 2-100 GeV/c. This is provided by two ring imaging Cherenkov detectors. The stringent requirements on the photon detectors are fully satisfied by the novel pixel hybrid photon detector, HPD. The HPD is a vacuum tube with a quartz window, S20 photo-cathode, cross-focusing electron optics and a silicon anode encapsulated within the tube. The anode is a 32*256 pixels hybrid detector, with a silicon sensor bump-bonded onto a readout chip containing 8192 channels with analogue front-end and digital read-out circuitry. An external magnetic field influences the trajectory of the photoelectrons and could thereby degrade the inherent excellent space resolution of the HPD. The HPDs must be operational in the fringe magnetic field of the LHCb magnet. This paper reports on an extensive experimental characterization of the distortion effects. The characterization has allowed the development of parameterisations and of a compensation algorithm. ...

  3. Silicon pixel-detector R&D for CLIC

    Science.gov (United States)

    Nürnberg, A.

    2016-11-01

    The physics aims at the future CLIC high-energy linear e+e- collider set very high precision requirements on the performance of the vertex and tracking detectors. Moreover, these detectors have to be well adapted to the experimental conditions, such as the time structure of the collisions and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of a few μm, ultra-low mass (~ 0.2%X0 per layer for the vertex region and ~ 1%X0 per layer for the outer tracker), very low power dissipation (compatible with air-flow cooling in the inner vertex region) and pulsed power operation, complemented with ~ 10 ns time stamping capabilities. A highly granular all-silicon vertex and tracking detector system is under development, following an integrated approach addressing simultaneously the physics requirements and engineering constraints. For the vertex-detector region, hybrid pixel detectors with small pitch (25 μm) and analog readout are explored. For the outer tracking region, both hybrid concepts and fully integrated CMOS sensors are under consideration. The feasibility of ultra-thin sensor layers is validated with Timepix3 readout ASICs bump bonded to active edge planar sensors with 50 μm to 150 μm thickness. Prototypes of CLICpix readout ASICs implemented in 6525 nm CMOS technology with 25 μm pixel pitch have been produced. Hybridisation concepts have been developed for interconnecting these chips either through capacitive coupling to active HV-CMOS sensors or through bump-bonding to planar sensors. Recent R&D achievements include results from beam tests with all types of hybrid assemblies. Simulations based on Geant4 and TCAD are used to validate the experimental results and to assess and optimise the performance of various detector designs.

  4. An EUDET/AIDA Pixel Beam Telescope for Detector Development

    CERN Document Server

    Perrey, Hanno

    2013-01-01

    A high resolution ($\\sigma 2 \\sim \\mu$) beam telescope based on monolithic active pixel sensors (MAPS) was developed within the EUDET collaboration. The telescope consists of six sensor planes using Mimosa26 MAPS with a pixel pitch of $18.4 \\mu$ and thinned down to $50 \\mu$. The excellent resolution, readout rate and DAQ integration capabilities made the telescope a primary test beam tool for many groups including several CERN based experiments. Within the new European detector infrastructure project AIDA the test beam telescope will be further extended in terms of cooling infrastructure, readout speed and precision. In order to provide a system optimized for the different requirements by the user community, a combination of various pixel technologies is foreseen. In this report the design of this even more flexible telescope with three different pixel technologies (TimePix, Mimosa, ATLAS FE-I4) will be presented. First test beam results with the HitOR signal provided by the FE-I4 integrated into the trigger...

  5. An EUDET/AIDA Pixel Beam Telescope for Detector Development

    CERN Document Server

    Rubinskiy, I

    2015-01-01

    A high resolution (σ∼2μm) beam telescope based on monolithic active pixel sensors (MAPS) was developed within the EUDET collaboration. The telescope consists of six monolithic active pixel sensor planes (Mimosa26) with a pixel pitch of 18.4 \\mu m and thinned down to 50 \\mu m. The excellent resolution, readout rate and DAQ integration capabilities made the telescope a primary test beam tool for many groups including several CERN based experiments. Within the European detector infrastructure project AIDA the test beam telescope is being further extended in terms of cooling and powering infrastructure, read-out speed, area of acceptance, and precision. In order to provide a system optimized for the different requirements by the user community a combination of various state-of-the-art pixel technologies is foreseen. Furthermore, new central dead-time-free trigger logic unit (TLU) has been developed to provide LHC-speed response with one-trigger-per-particle operating mode and a synchronous clock for all conn...

  6. Capacitively coupled hybrid pixel assemblies for the CLIC vertex detector

    CERN Document Server

    AUTHOR|(SzGeCERN)734627; Benoit, Mathieu; Dannheim, Dominik; Dette, Karola; Hynds, Daniel; Kulis, Szymon; Peric, Ivan; Petric, Marko; Redford, Sophie; Sicking, Eva; Valerio, Pierpaolo

    2016-01-01

    The vertex detector at the proposed CLIC multi-TeV linear e+e- collider must have minimal material content and high spatial resolution, combined with accurate time-stamping to cope with the expected high rate of beam-induced backgrounds. One of the options being considered is the use of active sensors implemented in a commercial high-voltage CMOS process, capacitively coupled to hybrid pixel ASICs. A prototype of such an assembly, using two custom designed chips (CCPDv3 as active sensor glued to a CLICpix readout chip), has been characterised both in the lab and in beam tests at the CERN SPS using 120 GeV/c positively charged hadrons. Results of these characterisation studies are presented both for single and dual amplification stages in the active sensor. Pixel cross-coupling results are also presented, showing the sensitivity to placement precision and planarity of the glue layer.

  7. Imaging performance of the hybrid pixel detectors XPAD3-S.

    Science.gov (United States)

    Brunner, F Cassol; Clemens, J C; Hemmer, C; Morel, C

    2009-03-21

    Hybrid pixel detectors, originally developed for tracking particles in high-energy physics experiments, have recently been used in material sciences and macromolecular crystallography. Their capability to count single photons and to apply a threshold on the photon energy suggests that they could be optimal digital x-ray detectors in low energy beams such as for small animal computed tomography (CT). To investigate this issue, we have studied the imaging performance of photon counting hybrid pixel detectors based on the XPAD3-S chip. Two detectors are considered, connected either to a Si or to a CdTe sensor, the latter being of interest for its higher efficiency. Both a standard 'International Electrotechnical Commission' (IEC) mammography beam and a beam used for mouse CT results published in the literature are employed. The detector stability, linearity and noise are investigated as a function of the dose for several imaging exposures ( approximately 0.1-400 microGy). The perfect linearity of both detectors is confirmed, but an increase in internal noise for counting statistics higher than approximately 5000 photons has been found, corresponding to exposures above approximately 110 microGy and approximately 50 microGy for the Si and CdTe sensors, respectively. The noise power spectrum (NPS), the modulation transfer function (MTF) and the detective quantum efficiency (DQE) are then measured for two energy threshold configurations (5 keV and 18 keV) and three doses ( approximately 3, 30 and 300 microGy), in order to obtain a complete estimation of the detector performances. In general, the CdTe sensor shows a clear superiority with a maximal DQE(0) of approximately 1, thanks to its high efficiency ( approximately 100%). The DQE of the Si sensor is more dependent on the radiation quality, due to the energy dependence of its efficiency its maximum is approximately 0.4 with respect to the softer radiation. Finally, we compare the XPAD3-S DQE with published curves of

  8. CMS 2017 Pixel detector replacement - A roll and B roll

    CERN Multimedia

    Paola Catapano

    2017-01-01

    On Thursday 2 March 2017 CERN physicists and engineers have carried out a highly complex operation right at the heart of one of the four main experiments of the Large Hadron Collider (LHC): the CMS detector, located 100 m below ground under French territory, at one of the LHC’s collision points. CMS is one of the four main detectors on the 27km LHC accelerator., and one of the two experiments which found the Higgs boson in 2012. The heart of the CMS experiment is the pixel detector, the innermost instrument in the very heart of the CMS apparatus, the very point where new particles, such as the Higgs boson, are produced by the energy of the proton proton collisions of the LHC accelerator. With thousands of silicon sensors, the new Pixel Tracker is now being upgraded to improve the particle-tracking capabilities of CMS. This operation, started on Tuesday Feb 28 when the first components of the new instrument were descended into the experiment’s cavern, is one of the most significant milestones ahead of the ...

  9. The CMS Silicon Pixel detector for HL-LHC

    CERN Document Server

    Steinbrueck, Georg

    2016-01-01

    The LHC is planning an upgrade program which will bring the luminosity to about 5~$\\times10^{34}$~cm$^{-2}$s$^{-1}$ in 2026, with the goal of an integrated luminosity of 3000 fb$^{-1}$ by the end of 2037. This High Luminosity scenario, HL-LHC, will present new challenges of higher data rates and increased radiation. To maintain its physics potential in this harsh environment, the CMS detector will undergo a major upgrade program known as the Phase II upgrade. The new Phase II pixel detector will require a high bandwidth readout system and highly radiation tolerant sensors and on-detector ASICs. Several technologies for the sensors are being studied. Serial powering schemes are under consideration to accommodate significant constraints on the system. These prospective designs, as well as new layout geometries that include very forward pixel discs with acceptance extended from $\\vert\\eta\\vert<2.4$ to $\\vert\\eta\\vert<4$, are presented together with performance estimates.

  10. Silicon pixel R&D for the CLIC detector

    CERN Document Server

    Hynds, Daniel

    2016-01-01

    The physics aims at the future CLIC high-energy linear e+e collider set very high precision requirements on the performance of the vertex and tracking detectors. Moreover, these detectors have to be well adapted to the experimental conditions, such as the time structure of the collisions and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of a few microns, ultra-low mass (~0.2% X0 per layer for the vertex region and ~1% X0 per layer for the outer tracker), very low power dissipation (compatible with air-flow cooling in the inner vertex region) and pulsed power operation, complemented with ~10 ns time stamping capabilities. A highly granular all-silicon vertex and tracking detector system is under development, following an integrated approach addressing simultaneously the physics requirements and engineering constraints. For the vertex-detector region, hy- brid pixel detectors with small pitch (25 μm) and analogue readout are explored. For the outer tracking region,...

  11. Silicon pixel-detector R&D for CLIC

    CERN Document Server

    AUTHOR|(SzGeCERN)718101

    2016-01-01

    The physics aims at the future CLIC high-energy linear e+e- collider set very high precision requirements on the performance of the vertex and tracking detectors. Moreover, these detectors have to be well adapted to the experimental conditions, such as the time structure of the collisions and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of a few μm, ultra-low mass (∼ 0.2% X${}_0$ per layer for the vertex region and ∼ 1 % X${}_0$ per layer for the outer tracker), very low power dissipation (compatible with air-flow cooling in the inner vertex region) and pulsed power operation, complemented with ∼ 10 ns time stamping capabilities. A highly granular all-silicon vertex and tracking detector system is under development, following an integrated approach addressing simultaneously the physics requirements and engineering constraints. For the vertex-detector region, hybrid pixel detectors with small pitch (25 μm) and analog readout are explored. For the outer trac...

  12. Development of a Detector Control System for the ATLAS Pixel detector in the HL-LHC

    Science.gov (United States)

    Lehmann, N.; Karagounis, M.; Kersten, S.; Zeitnitz, C.

    2016-11-01

    The upgrade of the LHC to the HL-LHC requires a new ITk detector. The innermost part of this new tracker is a pixel detector. The University of Wuppertal is developing a new DCS to monitor and control this new pixel detector. The current concept envisions three parallel paths of the DCS. The first path, called security path, is hardwired and provides an interlock system to guarantee the safety of the detector and human beings. The second path is a control path. This path is used to supervise the entire detector. The control path has its own communication lines independent from the regular data readout for reliable operation. The third path is for diagnostics and provides information on demand. It is merged with the regular data readout and provides the highest granularity and most detailed information. To reduce the material budget, a serial power scheme is the baseline for the pixel modules. A new ASIC used in the control path is in development at Wuppertal for this serial power chain. A prototype exists already and a proof of principle was demonstrated. Development and research is ongoing to guarantee the correct operation of the new ASIC in the harsh environment of the HL-LHC. The concept for the new DCS will be presented in this paper. A focus will be made on the development of the DCS chip, used for monitoring and control of pixel modules in a serial power chain.

  13. Tests of the gated mode for Belle II pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Prinker, Eduard [Max-Planck-Institute for Physics, Munich (Germany); Collaboration: Belle II-Collaboration

    2015-07-01

    DEPFET pixel detectors offer intrinsic amplification and very high signal to noise ratio. They form an integral building block for the vertex detector system of the Belle II experiment, which will start data taking in the year 2017 at the SuperKEKB Collider in Japan. A special Test board (Hybrid4) is used, which contains a small version of the DEPFET sensor with a read-out (DCD) and a steering chip (Switcher) attached, both controlled by a field-programmable gate array (FPGA) as the central interface to the computer. In order to keep the luminosity of the collider constant over time, the particle bunch currents have to be topped off by injecting additional bunches at a rate of 50 Hz. The particles in the daughter bunches produce a high rate of background (noisy bunches) for a short period of time, saturating the occupancy of the sensor. Operating the DEPFET sensor in a Gated Mode allows preserving the signals from collisions of normal bunches while protecting the pixels from background signals of the passing noisy bunches. An overview of the Gated Mode and first results is presented.

  14. The ultralight DEPFET pixel detector of the Belle II experiment

    Science.gov (United States)

    Luetticke, Florian

    2017-02-01

    An upgrade of the existing Japanese flavor factory (KEKB in Tsukuba, Japan) is under construction and foreseen for commissioning by the end of 2017. This new e+e- machine (SuperKEKB) will deliver an instantaneous luminosity 40 times higher than the luminosity world record set by KEKB. To fully exploit the increased number of events and provide high precision measurements of B-meson decay vertices in such a harsh environment, the Belle detector will be upgraded to Belle II, featuring a new silicon vertex detector with two pixel layers close to the interaction point based on the DEPFET (DEpleted P-channel Field Effect Transistor) technology. This technology combines particle detection together with in-pixel amplification by integrating a field effect transistor into a fully depleted silicon bulk. In Belle II, DEPFET sensors thinned down to 75 μm with low power consumption and low intrinsic noise will be used. The first large thin multi-chip production modules have been produced and characterization results on both large modules as well as small test systems will be presented in this contribution.

  15. A DEPFET pixel system for the ILC vertex detector

    CERN Document Server

    Trimpl, M; Kohrs, R; Krüger, H; Lodomez, P; Reuen, L; Sandow, C; Toerne, E; Velthuis, J J; Wermes, N; Andricek, L; Moser, H G; Richter, R H; Lutz, Gerhard; Giesen, F; Fischer, P; Peric, I

    2006-01-01

    We have developed a prototype system for the ILC vertex detector based on DEPFET pixels. The system operates a 128x64 pixel matrix and uses two dedicated microchips, the SWITCHER II chip for matrix steering and the CURO II chip for readout. The system development has been driven by the final ILC requirements which above all demand a detector thinned to 50 micron and a row wise read out with line rates of 20MHz and more. The targeted noise performance for the DEPFET technology is in the range of ENC=100e-. The functionality of the system has been demonstrated using different radioactive sources in an energy range from 6keV to 60keV. In recent test beam experiments using 6GeV electrons, a signal-to-noise ratio of S/N~120 has been achieved with present sensors being 450 micron thick. For improved DEPFET systems using 50 micron thin sensors in future, a signal-to-noise of 40 is expected.

  16. Optimization of the thermal performances of the Alpine Pixel Detector

    CERN Document Server

    Zhang, Zhan; Di Ciaccio, Lucia

    The ATLAS (A Toroidal LHC ApparatuS) detector is the largest detector of the Large Hadron Collider (LHC). One of the most important goals of ATLAS was to search for the missing piece of the Standard Model, the Higgs boson that had been found in 2012. In order to keep looking for the unknowns, it is planned to upgrade the LHC. The High Luminosity LHC (HL-LHC) is a novel configuration of the accelerator, aiming at increasing the luminosity by a factor five or more above the nominal LHC design. In parallel with the accelerator upgrade also the ATLAS will be upgraded to cope with detector aging and to achieve the same or better performance under increased event rate and radiation dose expected at the HL-LHC. This thesis discusses a novel design for the ATLAS Pixel Detector called the "Alpine" layout for the HL-LHC. To support this design, a local support structure is proposed, optimized and tested with an advanced CO2 evaporative cooling system. A numerical program called “CoBra” simulating the twophase heat ...

  17. Diamond Pixel Detectors and 3D Diamond Devices

    Science.gov (United States)

    Venturi, N.

    2016-12-01

    Results from detectors of poly-crystalline chemical vapour deposited (pCVD) diamond are presented. These include the first analysis of data of the ATLAS Diamond Beam Monitor (DBM). The DBM module consists of pCVD diamond sensors instrumented with pixellated FE-I4 front-end electronics. Six diamond telescopes, each with three modules, are placed symmetrically around the ATLAS interaction point. The DBM tracking capabilities allow it to discriminate between particles coming from the interaction point and background particles passing through the ATLAS detector. Also, analysis of test beam data of pCVD DBM modules are presented. A new low threshold tuning algorithm based on noise occupancy was developed which increases the DBM module signal to noise ratio significantly. Finally first results from prototypes of a novel detector using pCVD diamond and resistive electrodes in the bulk, forming a 3D diamond device, are discussed. 3D devices based on pCVD diamond were successfully tested with test beams at CERN. The measured charge is compared to that of a strip detector mounted on the same pCVD diamond showing that the 3D device collects significantly more charge than the planar device.

  18. A Novel Front-End ASIC With Post Digital Filtering and Calibration for CZT-Based PET Detector

    Energy Technology Data Exchange (ETDEWEB)

    Gao, W.; Yin, J.; Li, C.; Zeng, H.; Gao, D. [Institute of Microelectronics, School of Computer Science and Techonology, Northwestern Polytechnical University, Xi' an (China); Hu, Y. [Institut Pluridiscipline Hubert Curien, CNRS/UDS/IN2P3, Strasbourg (France)

    2015-07-01

    This paper presents a novel front-end electronics based on a front-end ASIC with post digital filtering and calibration dedicated to CZT detectors for PET imaging. A cascade amplifier based on split-leg topology is selected to realize the charge-sensitive amplifier (CSA) for the sake of low noise performances and the simple scheme of the power supplies. The output of the CSA is connected to a variable-gain amplifier to generate the compatible signals for the A/D conversion. A multi-channel single-slope ADC is designed to sample multiple points for the digital filtering and shaping. The digital signal processing algorithms are implemented by a FPGA. To verify the proposed scheme, a front-end readout prototype ASIC is designed and implemented in 0.35 μm CMOS process. In a single readout channel, a CSA, a VGA, a 10-bit ADC and registers are integrated. Two dummy channels, bias circuits, and time controller are also integrated. The die size is 2.0 mm x 2.1 mm. The input range of the ASIC is from 2000 e{sup -} to 100000 e{sup -}, which is suitable for the detection of the X-and gamma ray from 11.2 keV to 550 keV. The linearity of the output voltage is less than 1 %. The gain of the readout channel is 40.2 V/pC. The static power dissipation is about 10 mW/channel. The above tested results show that the electrical performances of the ASIC can well satisfy PET imaging applications. (authors)

  19. A CZT high efficiency detector with 3D spatial resolution for Laue lens applications

    DEFF Research Database (Denmark)

    Auricchio, N.; Basili, A.; Caroli, E.

    2010-01-01

    high performance focal plane detectors in order to exploit to the maximum the intrinsic capabilities of these new high energy telescopes. We describe the ongoing development of a three dimensional (3D) position sensitive device suitable as the basic unit of a high efficiency focal plane detector...... one collecting strip and 8 drift strips. The drift strips are biased by a voltage divider. The cathode is divided into 4 horizontal strips for the reconstruction of the third coordinate of the interaction. The final 3D prototype is made by packing 8 linear modules, each composed of one basic sensitive...... unit, bonded onto a supporting ceramic layer. The readout electronics implements the new RENA-3 Asics and the data handling system uses custom designed FPGA based electronics to provide both the ASIC operation and the acquisition logic....

  20. Development and characterization of diamond and 3D-silicon pixel detectors with ATLAS-pixel readout electronics

    Energy Technology Data Exchange (ETDEWEB)

    Mathes, Markus

    2008-12-15

    Hybrid pixel detectors are used for particle tracking in the innermost layers of current high energy experiments like ATLAS. After the proposed luminosity upgrade of the LHC, they will have to survive very high radiation fluences of up to 10{sup 16} particles per cm{sup 2} per life time. New sensor concepts and materials are required, which promise to be more radiation tolerant than the currently used planar silicon sensors. Most prominent candidates are so-called 3D-silicon and single crystal or poly-crystalline diamond sensors. Using the ATLAS pixel electronics different detector prototypes with a pixel geometry of 400 x 50 {mu}m{sup 2} have been built. In particular three devices have been studied in detail: a 3D-silicon and a single crystal diamond detector with an active area of about 1 cm{sup 2} and a poly-crystalline diamond detector of the same size as a current ATLAS pixel detector module (2 x 6 cm{sup 2}). To characterize the devices regarding their particle detection efficiency and spatial resolution, the charge collection inside a pixel cell as well as the charge sharing between adjacent pixels was studied using a high energy particle beam. (orig.)

  1. Optimization of <= 200 um pitch CZT detectors for future high-resolution X-ray instrumentation in astrophysics

    CERN Document Server

    Zajczyk, Anna; Dowkontt, Paul; Guo, Qingzhen; Kislat, Fabian; Krawczynski, Henric; De Geronimo, Gianluigi; Li, Shaorui; Beilicke, Matthias

    2015-01-01

    Cadmium Zinc Telluride and Cadmium Telluride are the detector materials of choice for the detection of X-rays in the X-ray energy band E >= 5keV with excellent spatial and spectral resolution and without cryogenic cooling. Owing to recent breakthroughs in grazing incidence mirror technology, next-generation hard X-ray telescopes will achieve angular resolution between 5 and 10 arc seconds - about an order of magnitude better than that of the NuSTAR hard X-ray telescope. As a consequence, the next generation of X-ray telescopes will require pixelated X-ray detectors with pixels on a grid with a lattice constant of <= 250um. Additional detector requirements include a low energy threshold of less than 5keV and an energy resolution of less than one keV. The science drivers for a high angular-resolution X-ray mission include studies and measurements of black hole spins, the cosmic evolution of super-massive black holes, active galactic nuclei feedback, and the behaviour of matter at very high densities. In this...

  2. Running experience with the DELPHI pixel detector reflections on design characteristics and system features

    CERN Document Server

    Heuser, J M

    1999-01-01

    The DELPHI experiment at LEP is the first collider experiment with hybrid pixel detectors contributing to its track reconstruction. The pixel detector has been installed in 1996 with the final DELPHI silicon tracker, an assembly of microstrip, ministrip and pixel detectors optimized for the operation at LEP2. It was completed for the physics period in 1997. The pixel detector comprises 1.2 million detector cells of 330*330 mu m/sup 2/. 152 detector modules are arranged in 4 inclined cone-shaped layers which cover polar angles from 10 degrees to 25 degrees . Experience on the system's features has been gained during three years of operation. The article intends to provide information on positive and critical aspects which might be useful for designers of pixel detector systems in forthcoming experiments. (4 refs).

  3. Micropattern gas detectors The CMS MSGC project and gaseous pixel detector applications

    CERN Document Server

    Bellazzini, R; Gariano, G; Latronico, L; Lumb, N; Moggi, A; Reale, S; Spandre, G; Massai, M M; Spezziga, M A; Toropin, A N; Costa, E; Soffitta, P; Pacella, D

    2001-01-01

    We report recent results from the development and testing of two types of micropattern gas detectors-micro-strip gas chambers and GEM- based devices with two types of pixel read-out. Thirty-two micro- strip gas chambers were tested in a high intensity hadron beam as a milestone for CERN's Compact Muon Solenoid (CMS) experiment. The detectors were operated with voltage settings corresponding to 98% hit detection efficiency at CMS for a total high intensity exposure period of 493 h. All of the requirements expected by the milestone- gain stability, number of lost strips, spark rate, etc.-were met, with wide margins. In a separate investigation, we have coupled PCB pixel read-out planes to GEM foils. In one case, 2 mm*2 mm pixels were fanned out to individual discriminators and scalers to provide very fast (2 MHz/pixel) read-out; this system has been used as an imaging device to provide diagnostic information in fusion experiments. The second type of device used smaller pixels (200 mu m squares) and a Flash-ADC ...

  4. The LHCb Vertex Locator (VELO) Pixel Detector Upgrade

    CERN Document Server

    Buchanan, Emma

    2017-01-01

    The LHCb experiment is designed to perform high-precision measurements of CP violation and the decays of beauty and charm hadrons at the Large Hadron Collider (LHC) at CERN. There is a planned upgrade during Long Shutdown 2 (LS2), expected in 2019, which will allow the detector to run at higher luminosities by transforming the entire readout to a trigger-less system. This will include a substantial upgrade of the Vertex Locator (VELO), the silicon tracker that surrounds the LHCb interaction region. The VELO is moving from silicon strip technology to hybrid pixel sensors, where silicon sensors are bonded to VeloPix ASICs. Sensor prototypes have undergone rigorous testing using the Timepix3 Telescope at the SPS, CERN. The main components of the upgrade are summarised and testbeam results presented.

  5. Towards a new generation of pixel detector readout chips

    CERN Document Server

    Campbell, M; Ballabriga, R.; Frojdh, E.; Heijne, E.; Llopart, X.; Poikela, T.; Tlustos, L.; Valerio, P.; Wong, W.

    2016-01-01

    The Medipix3 Collaboration has broken new ground in spectroscopic X-ray imaging and in single particle detection and tracking. This paper will review briefly the performance and limitations of the present generation of pixel detector readout chips developed by the Collaboration. Through Silicon Via technology has the potential to provide a significant improvement in the tile- ability and more flexibility in the choice of readout architecture. This has been explored in the context of 3 projects with CEA-LETI using Medipix3 and Timepix3 wafers. The next generation of chips will aim to provide improved spectroscopic imaging performance at rates compatible with human CT. It will also aim to provide full spectroscopic images with unprecedented energy and spatial resolution. Some of the opportunities and challenges posed by moving to a more dense CMOS process will be discussed.

  6. A generic readout environment for prototype pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Turqueti, Marcos, E-mail: turqueti@fnal.go [Fermi National Accelerator Laboratory, Kirk and Wilson Road, 60510-500 (United States); Rivera, Ryan; Prosser, Alan; Kwan, Simon [Fermi National Accelerator Laboratory, Kirk and Wilson Road, 60510-500 (United States)

    2010-11-01

    Pixel detectors for experimental particle physics research have been implemented with a variety of readout formats and potentially generate massive amounts of data. Examples include the PSI46 device for the Compact Muon Solenoid (CMS) experiment which implements an analog readout, the Fermilab FPIX2.1 device with a digital readout, and the Fermilab Vertically Integrated Pixel device. The Electronic Systems Engineering Department of the Computing Division at the Fermi National Accelerator Laboratory has developed a data acquisition system flexible and powerful enough to meet the various needs of these devices to support laboratory test bench as well as test beam applications. The system is called CAPTAN (Compact And Programmable daTa Acquisition Node) and is characterized by its flexibility, versatility and scalability by virtue of several key architectural features. These include a vertical bus that permits the user to stack multiple boards, a gigabit Ethernet link that permits high speed communications to the system and a core group of boards that provide specific processing and readout capabilities for the system. System software based on distributed computing techniques supports an expandable network of CAPTANs. In this paper, we describe the system architecture and give an overview of its capabilities.

  7. Pixel Detector Trial Assembly Test in the SR1 building

    CERN Document Server

    D. Giugni

    2004-01-01

    During the last two months the Pixel group [LBL, Milan and Wuppertal] made a successful integration test on the mechanics of the barrel. The scope of the test was to qualify the integration procedures and the various assembling tools. The test took place in the clean room of the SR1 building at CERN, where the detector has been assembled around a dummy beam pipe made of Stainless Steel. The process is rather complex: the shells come in two parts and they have to be clamped together to get the full shell. This operation is carried out by a dedicated tool which is shown to the right in the picture below. The layer 1 shell is clamped around a "service" pipe that will be used for moving the full layer to the integration tool [ITT] which is visible on the left. View of the tools devoted to the Pixel barrel integration in the SR1 building Also visible in the picture is the global frame that is actually held by the tool. It will engage the layers sliding onto the rails. The first two layers are sequentially...

  8. A germanium hybrid pixel detector with 55μm pixel size and 65,000 channels

    Science.gov (United States)

    Pennicard, D.; Struth, B.; Hirsemann, H.; Sarajlic, M.; Smoljanin, S.; Zuvic, M.; Lampert, M. O.; Fritzsch, T.; Rothermund, M.; Graafsma, H.

    2014-12-01

    Hybrid pixel semiconductor detectors provide high performance through a combination of direct detection, a relatively small pixel size, fast readout and sophisticated signal processing circuitry in each pixel. For X-ray detection above 20 keV, high-Z sensor layers rather than silicon are needed to achieve high quantum efficiency, but many high-Z materials such as GaAs and CdTe often suffer from poor material properties or nonuniformities. Germanium is available in large wafers of extremely high quality, making it an appealing option for high-performance hybrid pixel X-ray detectors, but suitable technologies for finely pixelating and bump-bonding germanium have not previously been available. A finely-pixelated germanium photodiode sensor with a 256 by 256 array of 55μm pixels has been produced. The sensor has an n-on-p structure, with 700μm thickness. Using a low-temperature indium bump process, this sensor has been bonded to the Medipix3RX photoncounting readout chip. Tests with the LAMBDA readout system have shown that the detector works successfully, with a high bond yield and higher image uniformity than comparable high-Z systems. During cooling, the system is functional around -80°C (with warmer temperatures resulting in excessive leakage current), with -100°C sufficient for good performance.

  9. X-ray micro-beam characterization of a small pixel spectroscopic CdTe detector

    Science.gov (United States)

    Veale, M. C.; Bell, S. J.; Seller, P.; Wilson, M. D.; Kachkanov, V.

    2012-07-01

    A small pixel, spectroscopic, CdTe detector has been developed at the Rutherford Appleton Laboratory (RAL) for X-ray imaging applications. The detector consists of 80 × 80 pixels on a 250 μm pitch with 50 μm inter-pixel spacing. Measurements with an 241Am γ-source demonstrated that 96% of all pixels have a FWHM of better than 1 keV while the majority of the remaining pixels have FWHM of less than 4 keV. Using the Diamond Light Source synchrotron, a 10 μm collimated beam of monochromatic 20 keV X-rays has been used to map the spatial variation in the detector response and the effects of charge sharing corrections on detector efficiency and resolution. The mapping measurements revealed the presence of inclusions in the detector and quantified their effect on the spectroscopic resolution of pixels.

  10. Readout electronics and test bench for the CMS Phase I pixel detector

    CERN Document Server

    Del Burgo, Riccardo

    2016-01-01

    The present CMS pixel detector will be replaced with an upgraded pixel system during the LHC extended technical stop in winter 2016/2017. The CMS Phase 1 pixel upgrade combines a new pixel readout chip, which minimizes detection inefficiencies, with several other design improvements to maintain the excellent tracking performance of CMS at the higher luminosity conditions foreseen for the coming years. The upgraded detector features new readout electronics which require detailed evaluation. For this purpose a test stand has been setup, including a slice of the CMS pixel DAQ system, all components of the upgraded readout chain together with a number of detector modules. The test stand allows for detailed evaluation and verification of all detector components, and is also crucial to develop tests and procedures to be used during the detector assembly and the commissioning and calibration of the detector. In this talk the system test and its functionalities will be described with a focus on the tests performed fo...

  11. Multi-Element CZT Array for Nuclear Safeguards Applications

    Science.gov (United States)

    Kwak, S.-W.; Lee, A.-R.; Shin, J.-K.; Park, U.-R.; Park, S.; Kim, Y.; Chung, H.

    2016-12-01

    Due to its electronic properties, a cadmium zinc telluride (CZT) detector has been used as a hand-held portable nuclear measurement instrument. However, a CZT detector has low detection efficiency because of a limitation of its single crystal growth. To address its low efficiency, we have constructed a portable four-CZT array based gamma-ray spectrometer consisting of a CZT array, electronics for signal processing and software. Its performance has been characterized in terms of energy resolution and detection efficiency using radioactive sources and nuclear materials. Experimental results showed that the detection efficiency of the four-CZT array based gamma-ray spectrometer was much higher than that of a single CZT detector in the array. The FWHMs of the CZT array were 9, 18, and 21 keV at 185.7, 662, and 1,332 keV, respectively. Some gamma-rays in a range of 100 keV to 200 keV were not clear in a single crystal detector while those from the CZT array system were observed to be clear. The energy resolution of the CZT array system was only slightely worse than those of the single CZT detectors. By combining several single crystals and summing signals from each single detector at a digital electronic circuit, the detection efficiency of a CZT array system increased without degradation of its energy resolution. The technique outlined in this paper shows a very promising method for designing a CZT-based gamma-ray spectroscopy that overcomes the fundamental limitations of a small volume CZT detector.

  12. From vertex detectors to inner trackers with CMOS pixel sensors

    Science.gov (United States)

    Besson, A.; Pérez, A. Pérez; Spiriti, E.; Baudot, J.; Claus, G.; Goffe, M.; Winter, M.

    2017-02-01

    The use of CMOS Pixel Sensors (CPS) for high resolution and low material vertex detectors has been validated with the 2014 and 2015 physics runs of the STAR-PXL detector at RHIC/BNL. This opens the door to the use of CPS for inner tracking devices, with 10-100 times larger sensitive area, which require therefore a sensor design privileging power saving, response uniformity and robustness. The 350 nm CMOS technology used for the STAR-PXL sensors was considered as too poorly suited to upcoming applications like the upgraded ALICE Inner Tracking System (ITS), which requires sensors with one order of magnitude improvement on readout speed and improved radiation tolerance. This triggered the exploration of a deeper sub-micron CMOS technology, Tower-Jazz 180 nm, for the design of a CPS well adapted for the new ALICE-ITS running conditions. This paper reports the R & D results for the conception of a CPS well adapted for the ALICE-ITS.

  13. Using the pixel detector for fast triggering in CMS

    CERN Document Server

    De Mattai, M

    2006-01-01

    The Standard Model of fundamental interactions (SM) has been extensively tested in many particle experiments during the last 25 years and it has proven to be extremely successful up to the energy scale typical of the weak force. Nevertheless, there is still no experimental evidence of the Higgs boson, one of the key components of the SM, responsible for the breaking of the electroweak symmetry and for the masses of the fermions and of the weak bosons. The Large Hadron Collider (LHC) is scheduled to provide the first proton on proton collision in 2008 at the center of mass energy of 14 Tev, an energy one order of magnitude higher than the regime explored so far. The CMS experiment is an omni-purpose experiment that will operate at the LHC, it will give insight into Standard Model physics and search for physics beyond the Standard Model. In this work we consider the usage of pixel detector information in the reconstruction of hadronic jets in events collected by the CMS detector under high luminosity running co...

  14. From vertex detectors to inner trackers with CMOS pixel sensors

    CERN Document Server

    Besson, A; Spiriti, E.; Baudot, J.; Claus, G.; Goffe, M.; Winter, M.

    2016-01-01

    The use of CMOS Pixel Sensors (CPS) for high resolution and low material vertex detectors has been validated with the 2014 and 2015 physics runs of the STAR-PXL detector at RHIC/BNL. This opens the door to the use of CPS for inner tracking devices, with 10-100 times larger sensitive area, which require therefore a sensor design privileging power saving, response uniformity and robustness. The 350 nm CMOS technology used for the STAR-PXL sensors was considered as too poorly suited to upcoming applications like the upgraded ALICE Inner Tracking System (ITS), which requires sensors with one order of magnitude improvement on readout speed and improved radiation tolerance. This triggered the exploration of a deeper sub-micron CMOS technology, Tower-Jazz 180 nm, for the design of a CPS well adapted for the new ALICE-ITS running conditions. This paper reports the R&D results for the conception of a CPS well adapted for the ALICE-ITS.

  15. Beam test results of the BTeV silicon pixel detector

    CERN Document Server

    Appel, J A

    2001-01-01

    We report the results of the BTeV silicon pixel detector tests carried out in the MTest beam at Fermilab in 1999-2000. The pixel detector spatial resolution has been studied as a function of track inclination, sensor bias, and readout threshold.

  16. Display of cosmic ray event going through the pixel detector taken on October 18th 2008

    CERN Multimedia

    ATLAS, Experiment

    2014-01-01

    Shown are the XY view (of SCT and pixels and of pixels alone) and an RZ view. The track has a hit in each of the layers in both the upper and the lower hemisphere. In the bottom of L0 there are even two hits due to a module overlap. Apart from the signal hits there is only one other hit in the pixel detector demonstrating the very low noise level in the detector.

  17. Commissioning of the upgraded ATLAS Pixel Detector for Run2 at LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00016406

    2016-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL), a fourth layer of pixel detectors, installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. An overview of the refurbishing of the Pixel Detector and of the IBL project as well as early performance tests using cosmic rays and beam data will be presented.

  18. Commissioning of the upgraded ATLAS Pixel Detector for Run2 at LHC

    Energy Technology Data Exchange (ETDEWEB)

    Dobos, Daniel, E-mail: daniel.dobos@cern.ch

    2016-07-11

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to the surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer, a fourth layer of pixel detectors, installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. An overview of the refurbishing of the Pixel Detector and of the IBL project as well as early performance tests using cosmic rays and beam data will be presented.

  19. Optical Readout in a Multi-Module System Test for the ATLAS Pixel Detector

    CERN Document Server

    Flick, T; Gerlach, P; Kersten, S; Mättig, P; Kirichu, S N; Reeves, K; Richter, J; Schultes, J; Flick, Tobias; Becks, Karl-Heinz; Gerlach, Peter; Kersten, Susanne; Maettig, Peter; Kirichu, Simon Nderitu; Reeves, Kendall; Richter, Jennifer; Schultes, Joachim

    2006-01-01

    The innermost part of the ATLAS experiment at the LHC, CERN, will be a pixel detector. The command messages and the readout data of the detector are transmitted over an optical data path. The readout chain consists of many components which are produced at several locations around the world, and must work together in the pixel detector. To verify that these parts are working together as expected a system test has been built up. In this paper the system test setup and the operation of the readout chain is described. Also, some results of tests using the final pixel detector readout chain are given.

  20. Qualification of the modules for the Phase 1 upgrade of the CMS forward pixel detector

    Science.gov (United States)

    Sandoval Gonzalez, Irving; CMS Collaboration

    2017-01-01

    The innermost component of the Compact Muon Solenoid (CMS) detector, the silicon pixel tracker, will be replaced by a new device in early 2017 to cope with the significant increase in instantaneous luminosity expected for the remainder of Run 2 of the Large Hadron Collider. The upgraded detector is composed of two subcomponents: the barrel pixel (BPIX) and the forward pixel (FPIX). In this work, we describe the testing and calibration procedures that the FPIX detector subcomponents underwent as well as the quality assurance criteria used for selecting the best detector modules for the final installation. NSF

  1. Radiation Damage Modeling for 3D Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Wallangen, Veronica; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of 10^15 neq/cm2 and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This poster presents the details of a new digitization model that includes radiation damage effects to the 3D Pixel sensors for the ATLAS Detector.

  2. Qualification of Barrel Pixel Detector Modules for the Phase 1 Upgrade of the CMS Vertex Detector

    CERN Document Server

    Kudella, Simon

    2016-01-01

    To withstand the higher particle rates of LHC Runs 2 and 3, with expected luminosities of up to $2\\times 10^{34}\\,\\mathrm{cm^{-2}s^{-1}}$, the current CMS pixel detector at the LHC will be replaced as part of the CMS Phase I Upgrade during the extended winter shutdown in 2016/17. The new pixel detector features a new geometry with one additional detector layer in the barrel region~(BPIX) and one pair of additional disks in the forward region~(FPIX), new digital readout chips as well as a new CO$_{2}$-based cooling system for both the barrel and forward region. The BPIX detector module production is summarized, with special focus on the different stages of quality assurance. The quality tests as well as the calibrations which all produced modules undergo in a temperature and humidity controlled environment are described. Exemplarily, the KIT/Aachen production line and its subprocesses are presented together with its quality and yields.

  3. Small-Scale Readout System Prototype for the STAR PIXEL Detector

    Energy Technology Data Exchange (ETDEWEB)

    Szelezniak, Michal; Anderssen, Eric; Greiner, Leo; Matis, Howard; Ritter, Hans Georg; Stezelberger, Thorsten; Sun, Xiangming; Thomas, James; Vu, Chinh; Wieman, Howard

    2008-10-10

    Development and prototyping efforts directed towards construction of a new vertex detector for the STAR experiment at the RHIC accelerator at BNL are presented. This new detector will extend the physics range of STAR by allowing for precision measurements of yields and spectra of particles containing heavy quarks. The innermost central part of the new detector is a high resolution pixel-type detector (PIXEL). PIXEL requirements are discussed as well as a conceptual mechanical design, a sensor development path, and a detector readout architecture. Selected progress with sensor prototypes dedicated to the PIXEL detector is summarized and the approach chosen for the readout system architecture validated in tests of hardware prototypes is discussed.

  4. Photoelectric X-ray Polarimetry with Gas Pixel Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bellazzini, Ronaldo; Brez, Alessandro [INFN Pisa Largo B. Pontecorvo 3, I-56127 Pisa (Italy); Costa, Enrico [INAF/IASF Rome Via del Fosso del Cavaliere 100, I-00133 Rome (Italy); Minuti, Massimo [INFN Pisa Largo B. Pontecorvo 3, I-56127 Pisa (Italy); Muleri, Fabio [INAF/IASF Rome Via del Fosso del Cavaliere 100, I-00133 Rome (Italy); Pinchera, Michele [INFN Pisa Largo B. Pontecorvo 3, I-56127 Pisa (Italy); Rubini, Alda; Soffitta, Paolo [INAF/IASF Rome Via del Fosso del Cavaliere 100, I-00133 Rome (Italy); Spandre, Gloria, E-mail: Gloria.Spandre@pi.infn.it [INFN Pisa Largo B. Pontecorvo 3, I-56127 Pisa (Italy)

    2013-08-21

    The Gas Pixel Detector, recently developed and continuously improved by Pisa-INFN in collaboration with IASF-Roma (INAF), can visualize the tracks produced within a low Z gas by photoelectrons of few keV. By reconstructing the impact point and the original direction of the photoelectrons, the GPD can measure the polarization plane of X-Ray photons, while preserving the information on the absorption point, the energy and the time of arrival of individual photons. Applied to X-ray Astrophysics, in the focus of grazing incidence telescopes, it can perform angular and energy resolved polarimetry with a large improvement of sensitivity, when compared with the conventional techniques of Bragg diffraction at 45° and Compton scattering around 90°. This configuration has been the basis of POLARIX and HXMT, two pathfinder missions, and was included in the baseline design of IXO, the very large X-ray telescope under study by NASA, ESA and JAXA. We have recently improved the design of this low energy polarimeter (2–10 keV) by modifying the geometry of the absorption cell to minimize any systematic effect that could leave a residual polarization signal for non-polarized source. We will report on the testing of this new concept.

  5. Pixel readout ASIC for an APD based 2D X-ray hybrid pixel detector with sub-nanosecond resolution

    Energy Technology Data Exchange (ETDEWEB)

    Thil, Ch., E-mail: christophe.thil@ziti.uni-heidelberg.d [Heidelberg University, Institute of Computer Engineering, B6, 26, 68161 Mannheim (Germany); Baron, A.Q.R. [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Fajardo, P. [ESRF, Polygone Scientifique Louis Neel, 6, rue Jules Horowitz, 38000 Grenoble (France); Fischer, P. [Heidelberg University, Institute of Computer Engineering, B6, 26, 68161 Mannheim (Germany); Graafsma, H. [DESY, Notkestrasse 85, 22607 Hamburg (Germany); Rueffer, R. [ESRF, Polygone Scientifique Louis Neel, 6, rue Jules Horowitz, 38000 Grenoble (France)

    2011-02-01

    The fast response and the short recovery time of avalanche photodiodes (APDs) in linear mode make those devices ideal for direct X-ray detection in applications requiring high time resolution or counting rate. In order to provide position sensitivity, the XNAP project aims at creating a hybrid pixel detector with nanosecond time resolution based on a monolithic APD sensor array with 32 x32 pixels covering about 1 cm{sup 2} active area. The readout is implemented in a pixelated front-end ASIC suited for the readout of such arrays, matched to pixels of 280{mu}mx280{mu}m size. Every single channel features a fast transimpedance amplifier, a discriminator with locally adjustable threshold and two counters with high dynamic range and counting speed able to accumulate X-ray hits with no readout dead time. Additionally, the detector can be operated in list mode by time-stamping every single event with sub-nanosecond resolution. In a first phase of the project, a 4x4 pixel test module is built to validate the conceptual design of the detector. The XNAP project is briefly presented and the performance of the readout ASIC is discussed.

  6. Development of hybrid photon detectors with integrated silicon pixel readout for the RICH counters of LHCb

    CERN Document Server

    Alemi, M; Formenti, F; Gys, Thierry; Piedigrossi, D; Puertolas, D; Rosso, E; Snoeys, W; Wyllie, Ken H

    1999-01-01

    We report on the ongoing work towards a hybrid photon detector with integrated silicon pixel readout for the ring imaging Cherenkov detectors of the LHCb experiment at the Large Hadron Collider at CERN. The photon detector is based $9 on a cross-focussed image intensifier tube geometry where the image is de-magnified by a factor of 4. The anode consists of a silicon pixel array, bump-bonded to a fast, binary readout chip with matching pixel electronics. The $9 performance of a half-scale prototype is presented, together with the developments and tests of a full-scale tube with large active area. Specific requirements for pixel front-end and readout electronics in LHCb are outlined, and $9 recent results obtained from pixel chips applicable to hybrid photon detector design are summarized.

  7. The upgraded Pixel Detector of the ATLAS Experiment for Run 2 at the Large Hadron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Backhaus, M., E-mail: malte.backhaus@cern.ch

    2016-09-21

    During Run 1 of the Large Hadron Collider (LHC), the ATLAS Pixel Detector has shown excellent performance. The ATLAS collaboration took advantage of the first long shutdown of the LHC during 2013 and 2014 and extracted the ATLAS Pixel Detector from the experiment, brought it to surface and maintained the services. This included the installation of new service quarter panels, the repair of cables, and the installation of the new Diamond Beam Monitor (DBM). Additionally, a completely new innermost pixel detector layer, the Insertable B-Layer (IBL), was constructed and installed in May 2014 between a new smaller beam pipe and the existing Pixel Detector. With a radius of 3.3 cm the IBL is located extremely close to the interaction point. Therefore, a new readout chip and two new sensor technologies (planar and 3D) are used in the IBL. In order to achieve best possible physics performance the material budget was improved with respect to the existing Pixel Detector. This is realized using lightweight staves for mechanical support and a CO{sub 2} based cooling system. This paper describes the improvements achieved during the maintenance of the existing Pixel Detector as well as the performance of the IBL during the construction and commissioning phase. Additionally, first results obtained during the LHC Run 2 demonstrating the distinguished tracking performance of the new Four Layer ATLAS Pixel Detector are presented.

  8. Performance Studies of Pixel Hybrid Photon Detectors for the LHCb RICH Counters

    CERN Document Server

    Aglieri Rinella, G; Piedigrossi, D; Van Lysebetten, A

    2004-01-01

    The Pixel Hybrid Photon Detector is a vacuum tube with a multi-alkali photo cathode, high voltage cross-focused electron optics and an anode consisting of a silicon pixel detector bump-bonded to a readout CMOS electronic chip fully encapsulated in the device. The Pixel HPD fulfils the requirements of the Ring Imaging Cherenkov counters of the LHCb experiment at LHC. The performances of the Pixel HPD will be discussed with reference to laboratory measurements, Cherenkov light imaging in recent beam tests, image distortions due to a magnetic field.

  9. Performance studies of pixel hybrid photon detectors for the LHCb RICH counters

    CERN Document Server

    Aglieri-Rinella, G; Piedigrossi, D; Van Lysebetten, A

    2006-01-01

    The Pixel Hybrid Photon Detector is a vacuum tube with a multi-alkali photo cathode, high voltage cross-focused electron optics and an anode consisting of a silicon pixel detector bump-bonded to a readout CMOS electronic chip fully encapsulated in the device. The Pixel HPD fulfils the requirements of the Ring Imaging Cherenkov counters of the LHCb experiment at LHC. The performances of the Pixel HPD will be discussed with reference to laboratory measurements, Cherenkov light imaging in recent beam tests, image distortions due to a magnetic field.

  10. A study on CZT and scintillator based micro-PETs with compton tracing technology

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Chang Yeon; Lee, Won Ho [Dept. of Bio-convergence Engineering, Korea University Graduate School, Seoul (Korea, Republic of)

    2015-10-15

    In this research, the performance of micro-PET with CZT semiconductor was compared with those with LYSO and LGSO scintillators based on detection efficiency and the quality of reconstructed images. Compton and conventional PET system with three detector materials were evaluated and compared with each other. The conventional PETs widely used in clinics generally consisted of lutetium series scintillators such as LSO, LYSO or LGSO. These scintillators have high atomic number and density, and hence, their detection efficiencies are very high. Even though the atomic number and density of CZT were relatively lower than those of scintillators resulting in less detection efficiency, the pixellized CZTs showed much higher position resolution than conventional detectors. Moreover, pixellized CZT can precisely track the interaction position inside detectors, in which Compton scattering as well as photoelectric events can be effective interaction, and hence, the detection efficiency improves significantly. For all material, the efficiency of Compton PETs was always higher than that of conventional PETs, and hence the image quality was also improved by using Compton PET technology.

  11. Modeling Inter-Pixel Crosstalk in Teledyne Imaging Sensors H4RG Detectors

    CERN Document Server

    Dudik, R P; Dorland, B N; Veillette, D; Waczynski, A; Lane, B; Loose, M; Kan, E; Waterman, J; Pravdo, S

    2012-01-01

    CMOS-hybrid arrays have recently surfaced as competitive optical detectors for use in ground- and space-based astronomy. One source of error in these detectors that does not appear in more traditional CCD arrays is the inter-pixel capacitance component of crosstalk. In this paper we use a single pixel reset method to model inter-pixel capacitance (IPC). We combine this IPC model with a model for charge diffusion to estimate the total crosstalk on H4RG arrays. Finally, we compare our model results to Fe55 data obtained using an astrometric camera built to test the H4RG-B0 generation detectors.

  12. Defect Measurements and Performance Testing of CZT Detectors Using I-DLTS, TCT, I-V, C-V and γ-Ray Spectroscopy

    Science.gov (United States)

    Gul, Rubi; Li, Zheng; Keeter, Kara; Rodriguez, Rene; James, Ralph

    2008-05-01

    Performance testing and the measurement of the defect levels of CZT detectors from different manufacturers are investigated by means of I-DLTS (Current Deep Level Transient Spectroscopy), TCT (Transient Charge Technique), I-V, C-V and γ-Ray Spectroscopy. Studies include measuring defects parameters such as energy levels in the band gap, carrier capture cross-section and defect density have been determined by using I-DLTS. The space charge density, induced current and collected charge were obtained by using TCT. Detector's electric characteristics and detection performance tests are carried out by using I-V, C-V and γ-Ray Spectroscopy. I-DLTS data is collected in the temperature range of 10-330 K. Different mid-band energy traps, ranging from Ec-0.01 eV to Ec-0.31 eV, mostly native acceptor defects, are identified. The TCT parameters are obtained by measuring laser induced current transients with 50-1100 V bias voltages across the detector. The maximum value of collected electrons and the typical measured space charge density, at 1100V is found of the order of 10^10. Resistivity, performance and depletion of the detectors are determined by I-V and γ-Ray Spectroscopy.

  13. X-ray imaging with photon counting hybrid semiconductor pixel detectors

    CERN Document Server

    Manolopoulos, S; Campbell, M; Snoeys, W; Heijne, Erik H M; Pernigotti, E; Raine, C; Smith, K; Watt, J; O'Shea, V; Ludwig, J; Schwarz, C

    1999-01-01

    Semiconductor pixel detectors, originally developed for particle physics experiments, have been studied as X-ray imaging devices. The performance of devices using the OMEGA 3 read-out chip bump-bonded to pixellated silicon semiconductor detectors is characterised in terms of their signal-to-noise ratio when exposed to 60 kVp X-rays. Although parts of the devices achieve values of this ratio compatible with the noise being photon statistics limited, this is not found to hold for the whole pixel matrix, resulting in the global signal-to-noise ratio being compromised. First results are presented of X-ray images taken with a gallium arsenide pixel detector bump-bonded to a new read-out chip, (MEDIPIX), which is a single photon counting read-out chip incorporating a 15-bit counter in every pixel. (author)

  14. X-ray imaging with photon counting hybrid semiconductor pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Manolopoulos, S.; Bates, R.; Campbell, M.; Snoeys, W.; Heijne, E.; Pernigotti, E.; Raine, C.; Smith, K. E-mail: k.smith@physics.gla.ac.uk; Watt, J.; O' Shea, V.; Ludwig, J.; Schwarz, C

    1999-09-11

    Semiconductor pixel detectors, originally developed for particle physics experiments, have been studied as X-ray imaging devices. The performance of devices using the {omega}3 read-out chip bump-bonded to pixellated silicon semiconductor detectors is characterised in terms of their signal-to-noise ratio when exposed to 60 kVp X-rays. Although parts of the devices achieve values of this ratio compatible with the noise being photon statistics limited, this is not found to hold for the whole pixel matrix, resulting in the global signal-to-noise ratio being compromised. First results are presented of X-ray images taken with a gallium arsenide pixel detector bump-bonded to a new read-out chip, (MEDIPIX), which is a single photon counting read-out chip incorporating a 15-bit counter in every pixel. (author)

  15. Instruments of RT-2 Experiment onboard CORONASPHOTON and their test and evaluation III: Coded Aperture Mask and Fresnel Zone Plates in RT-2/CZT Payload

    CERN Document Server

    Nandi, Anuj; Debnath, D; Chakrabarti, Sandip K; Kotoch, T B; Sarkar, R; Yadav, Vipin K; Girish, V; Rao, A R; Bhattacharya, D; 10.1007/s10686-010-9184-3

    2010-01-01

    Imaging in hard X-rays of any astrophysical source with high angular resolution is a challenging job. Shadow-casting technique is one of the most viable options for imaging in hard X-rays. We have used two different types of shadow-casters, namely, Coded Aperture Mask (CAM) and Fresnel Zone Plate (FZP) pair and two types of pixellated solid-state detectors, namely, CZT and CMOS in RT-2/CZT payload, the hard X-ray imaging instrument onboard the CORONAS-PHOTON satellite. In this paper, we present the results of simulations with different combinations of coders (CAM & FZP) and detectors that are employed in the RT-2/CZT payload. We discuss the possibility of detecting transient Solar flares with good angular resolution for various combinations. Simulated results are compared with laboratory experiments to verify the consistency of the designed configuration.

  16. The Upgraded Pixel Detector of the ATLAS Experiment for Run-2

    CERN Document Server

    Ferrere, Didier; The ATLAS collaboration

    2016-01-01

    Run-2 of the LHC is providing new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 at a radius of 3.3 cm between the existing Pixel Detector and a new smaller radius beam-pipe. The new detector, built to cope with high radiation and expected occupancy, is the first large scale application of 3D detectors and CMOS 130nm technology. In addition the Pixel detector was refurbished with a new service quarter panel to recover about 3% of defective modules lost during run-1 and a new optical readout system to readout the data at higher speed while reducing the occupancy when running with increased luminosity. The commissioning and performance of the 4-layer Pixel Detector, in particular the IBL, will be presented, using collision data.

  17. The upgraded Pixel Detector of the ATLAS experiment for Run-2 at the Large Hadron Collider

    CERN Document Server

    Giordani, MarioPaolo; The ATLAS collaboration

    2016-01-01

    Run-2 of the LHC is providing new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 at a radius of 3.3 cm between the existing Pixel Detector and a new smaller radius beam-pipe. The new detector, built to cope with high radiation and expected occupancy, is the first large scale application of 3D detectors and CMOS 130nm technology. In addition the Pixel detector was refurbished with a new service quarter panel to recover about 3% of defective modules lost during run-1 and a new optical readout system to readout the data at higher speed while reducing the occupancy when running with increased luminosity. The commissioning and performance of the 4-layer Pixel Detector, in particular the IBL, will be presented, using collision data.

  18. The Upgraded Pixel Detector of the ATLAS Experiment for Run-2 at the LHC

    CERN Document Server

    Giordani, MarioPaolo; The ATLAS collaboration

    2016-01-01

    Run-2 of the LHC is providing new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 at a radius of 3.3 cm between the existing Pixel Detector and a new smaller radius beam-pipe. The new detector, built to cope with high radiation and expected occupancy, is the first large scale application of 3D detectors and CMOS 130 nm technology. In addition the Pixel detector was refurbished with a new service quarter panel to recover about 3% of defective modules lost during run-1 and a new optical readout system to readout the data at higher speed while reducing the occupancy when running with increased luminosity. The commissioning and performance of the 4-layer Pixel Detector, in particular the IBL, will be presented using collision data.

  19. Efficient phase contrast imaging in STEM using a pixelated detector. Part II: Optimisation of imaging conditions

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hao, E-mail: hao.yang@materials.ox.ac.uk [University of Oxford, Department of Materials. Parks Rd, Oxford OX1 3PH (United Kingdom); Pennycook, Timothy J.; Nellist, Peter D. [University of Oxford, Department of Materials. Parks Rd, Oxford OX1 3PH (United Kingdom); EPSRC SuperSTEM Facility, Daresbury Laboratory, WA4 4AD (United Kingdom)

    2015-04-15

    In Part I of this series of two papers, we demonstrated the formation of a high efficiency phase-contrast image at atomic resolution using a pixelated detector in the scanning transmission electron microscope (STEM) with ptychography. In this paper we explore the technique more quantitatively using theory and simulations. Compared to other STEM phase contrast modes including annular bright field (ABF) and differential phase contrast (DPC), we show that the ptychographic phase reconstruction method using pixelated detectors offers the highest contrast transfer efficiency and superior low dose performance. Applying the ptychographic reconstruction method to DPC segmented detectors also improves the detector contrast transfer and results in less noisy images than DPC images formed using difference signals. We also find that using a minimum array of 16×16 pixels is sufficient to provide the highest signal-to-noise ratio (SNR) for imaging beam sensitive weak phase objects. Finally, the convergence angle can be adjusted to enhance the contrast transfer based on the spatial frequencies of the specimen under study. - Highlights: • High efficiency phase contrast transfer function (PCTF) can be achieved using pixelated detectors followed by a ptychographic reconstruction. • Ptychographic reconstruction offers the highest PCTF across the entire spatial frequency range compared to DPC and ABF. • Image simulations show that a ptychographic reconstruction using pixelated detectors offers a superior low dose performance for imaging weak phase objects. • Optimisation of imaging conditions using pixelated detectors are discussed by considering the contrast transfer function for various cases.

  20. The simulation of charge sharing in semiconductor X-ray pixel detectors

    CERN Document Server

    Mathieson, K; O'Shea, V; Passmore, M S; Rahman, M; Smith, K M; Watt, J; Whitehill, C

    2002-01-01

    Two simulation packages were used to model the sharing of charge, due to the scattering and diffusion of carriers, between adjacent pixel elements in semiconductors X-ray detectors. The X-ray interaction and the consequent multiple scattering was modelled with the aid of the Monte Carlo package, MCNP. The resultant deposited charge distribution was then used to create the charge cloud profile in the finite element semiconductor simulation code MEDICI. The analysis of the current pulses induced on pixel electrodes for varying photon energies was performed for a GaAs pixel detector. For a pixel pitch of 25 mu m, the charge lost to a neighbouring pixel was observed to be constant, at 0.6%, through the energies simulated. Ultimately, a fundamental limit on the pixel element size for imaging and spectroscopic devices may be set due to these key physical principles.

  1. Performance study of new pixel hybrid photon detector prototypes for the LHCb RICH counters

    CERN Document Server

    Moritz, M; Allebone, L; Campbell, M; Gys, Thierry; Newby, C; Pickford, A; Piedigrossi, D; Wyllie, K

    2004-01-01

    A pixel Hybrid Photon Detector was developed according to the specific requirements of the LHCb ring imaging Cerenkov counters. This detector comprises a silicon pixel detector bump-bonded to a binary readout chip to achieve a 25 ns fast readout and a high signal-to-noise ratio. The detector performance was characterized by varying the pixel threshold, the tube high voltage, the silicon bias voltage and by the determination of the photoelectron detection efficiency. Furthermore accelerated aging and high pixel occupancy tests were performed to verify the long term stability. The results were obtained using Cerenkov light and a fast pulsed light emitting diode. All measurements results are within the expectations and fulfill the design goals. (8 refs).

  2. Pixel Detector Developments for Tracker Upgrades of the High Luminosity LHC

    CERN Document Server

    Meschini, Marco; Dalla Betta, G. F; Dinardo, Mauro; Giacomini, G; Menasce, Dario; Mendicino, R; Messineo, Alberto; Moroni, Luigi; Ronchin, S; Sultan, D.M.S; Uplegger, Lorenzo; Viliani, Lorenzo; Zoi, Irene; Zuolo, Davide

    2017-01-01

    and 3D devices. The results on the 3D pixel sensors before irradiation are very satisfactory and % make us confident support the conclusion that columnar devices are % 3D devices very good candidates for the inner layers of the upgrade pixel detectors.

  3. Characterization of edgeless pixel detectors coupled to Medipix2 readout chip

    Science.gov (United States)

    Kalliopuska, Juha; Tlustos, Lukas; Eränen, Simo; Virolainen, Tuula

    2011-08-01

    VTT has developed a straightforward and fast process to fabricate four-side buttable (edgeless) microstrip and pixel detectors on 6 in. (150 mm) wafers. The process relies on advanced ion implantation to activate the edges of the detector instead of using polysilicon. The article characterizes 150 μm thick n-on-n edgeless pixel detector prototypes with a dead layer at the edge below 1 μm. Electrical and radiation response characterization of 1.4×1.4 cm2 n-on-n edgeless detectors has been done by coupling them to the Medipix2 readout chips. The distance of the detector's physical edge from the pixels was either 20 or 50 μm. The leakage current of flip-chip bonded edgeless Medipix2 detector assembles were measured to be ˜90 nA/cm2 and no breakdown was observed below 110 V. Radiation response characterization includes X-ray tube and radiation source responses. The characterization results show that the detector's response at the pixels close to the physical edge of the detector depend dramatically on the pixel-to-edge distance.

  4. 3D track reconstruction capability of a silicon hybrid active pixel detector

    Science.gov (United States)

    Bergmann, Benedikt; Pichotka, Martin; Pospisil, Stanislav; Vycpalek, Jiri; Burian, Petr; Broulim, Pavel; Jakubek, Jan

    2017-06-01

    Timepix3 detectors are the latest generation of hybrid active pixel detectors of the Medipix/Timepix family. Such detectors consist of an active sensor layer which is connected to the readout ASIC (application specific integrated circuit), segmenting the detector into a square matrix of 256 × 256 pixels (pixel pitch 55 μm). Particles interacting in the active sensor material create charge carriers, which drift towards the pixelated electrode, where they are collected. In each pixel, the time of the interaction (time resolution 1.56 ns) and the amount of created charge carriers are measured. Such a device was employed in an experiment in a 120 GeV/c pion beam. It is demonstrated, how the drift time information can be used for "4D" particle tracking, with the three spatial dimensions and the energy losses along the particle trajectory (dE/dx). Since the coordinates in the detector plane are given by the pixelation ( x, y), the x- and y-resolution is determined by the pixel pitch (55 μm). A z-resolution of 50.4 μm could be achieved (for a 500 μm thick silicon sensor at 130 V bias), whereby the drift time model independent z-resolution was found to be 28.5 μm.

  5. Digital column readout architectures for hybrid pixel detector readout chips

    CERN Document Server

    Poikela, T; Westerlund, T; Buytaert, J; Campbell, M; De Gaspari, M; Llopart, X; Wyllie, K; Gromov, V; Kluit, R; van Beuzekom, M; Zappon, F; Zivkovic, V; Brezina, C; Desch, K; Fu, Y; Kruth, A

    2014-01-01

    In this paper, two digital column architectures suitable for sparse readout of data from a pixel matrix in trigger-less applications are presented. Each architecture reads out a pixel matrix of 256 x 256 pixels with a pixel pitch of 55 µm. The first architecture has been implemented in the Timepix3 chip, and this is presented together with initial measurements. Simulation results and measured data are compared. The second architecture has been designed for Velopix, a readout chip planned for the LHCb VELO upgrade. Unlike Timepix3, this has to be tolerant to radiation-induced single-event effects. Results from post-layout simulations are shown with the circuit architectures.

  6. Investigation of photon counting pixel detectors for X-ray spectroscopy and imaging

    Energy Technology Data Exchange (ETDEWEB)

    Talla, Patrick Takoukam

    2011-04-07

    The Medipix2 and Medipix3 detectors are hybrid pixelated photon counting detectors with a pixel pitch of 55 {mu}m. The sensor material used in this thesis was silicon. Because of their small pixel size they suffer from charge sharing i.e. an incoming photon can be registered by more than one pixel. In order to correct for charge sharing due to lateral diffusion of charge carriers, the Medipix3 detector was developed: with its Charge Summing Mode, the charge collected in a cluster of 2 x 2 pixel is added up and attributed to only one pixel whose counter is incremented. The adjustable threshold of the detectors allows to count the photons and to gain information on their energy. The main purposes of the thesis are to investigate spectral and imaging properties of pixelated photon counting detectors from the Medipix family such as Medipix2 and Medipix3. The investigations are based on simulations and measurements. In order to investigate the spectral properties of the detectors measurements were performed using fluorescence lines of materials such as molybdenum, silver but also some radioactive sources such as Am-241 or Cd-109. From the measured data, parameters like the threshold dispersion and the gain variation from pixel-to-pixel were extracted and used as input in the Monte Carlo code ROSI to model the responses of the detector to monoenergetic photons. The measured data are well described by the simulations for Medipix2 and for Medipix3 operating in Charge Summing Mode. Due to charge sharing and due to the energy dependence of attenuation processes in silicon and to Compton scattering the incoming and the measured spectrum differ substantially from each other. Since the responses to monoenergetic photons are known, a deconvolution was performed to determine the true incoming spectrum. Several direct and iterative methods were successfully applied on measured and simulated data of an X-ray tube and radioactive sources. The knowledge of the X-ray spectrum is

  7. Modelling of the small pixel effect in gallium arsenide X-ray imaging detectors

    CERN Document Server

    Sellin, P J

    1999-01-01

    A Monte Carlo simulation has been carried out to investigate the small pixel effect in highly pixellated X-ray imaging detectors fabricated from semi-insulating gallium arsenide. The presence of highly non-uniform weighting fields in detectors with a small pixel geometry causes the majority of the induced signal to be generated when the moving charges are close to the pixellated contacts. The response of GaAs X-ray imaging detectors is further complicated by the presence of charge trapping, particularly of electrons. In this work detectors are modelled with a pixel pitch of 40 and 150 mu m, and with thicknesses of 300 and 500 mu m. Pulses induced in devices with 40 mu m pixels are due almost totally to the movement of the lightly-trapped holes and can exhibit significantly higher charge collection efficiencies than detectors with large electrodes, in which electron trapping is significant. Details of the charge collection efficiencies as a function of interaction depth in the detector and of the incident phot...

  8. Imaging and spectroscopic performance studies of pixellated CdTe Timepix detector

    Science.gov (United States)

    Maneuski, D.; Astromskas, V.; Fröjdh, E.; Fröjdh, C.; Gimenez, E. N.; Marchal, J.; O'Shea, V.; Stewart, G.; Tartoni, N.; Wilhelm, H.; Wraight, K.; Zain, R. M.

    2012-01-01

    In this work the results on imaging and spectroscopic performances of 14 × 14 × 1 mm CdTe detectors with 55 × 55 μm and 110 × 110 μm pixel pitch bump-bonded to a Timepix chip are presented. The performance of the 110 × 110 μm pixel detector was evaluated at the extreme conditions beam line I15 of the Diamond Light Source. The energy of X-rays was set between 25 and 77 keV. The beam was collimated through the edge slits to 20 μm FWHM incident in the middle of the pixel. The detector was operated in the time-over-threshold mode, allowing direct energy measurement. Energy in the neighbouring pixels was summed for spectra reconstruction. Energy resolution at 77 keV was found to be ΔE/E = 3.9%. Comparative imaging and energy resolution studies were carried out between two pixel size detectors with a fluorescence target X-ray tube and radioactive sources. The 110 × 110 μm pixel detector exhibited systematically better energy resolution in comparison to 55 × 55 μm. An imaging performance of 55 × 55 μm pixellated CdTe detector was assessed using the Modulation Transfer Function (MTF) technique and compared to the larger pixel. A considerable degradation in MTF was observed for bias voltages below -300 V. Significant room for improvement of the detector performance was identified both for imaging and spectroscopy and is discussed.

  9. Direct charge sharing observation in single-photon-counting pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, G. [Centro Nacional de Microelectronica, IMB-CNM (CSIC), Barcelona 08193 (Spain)]. E-mail: Giulio.Pellegrini@cnm.es; Maiorino, M. [IFAE - Institut de Fisica d' Altes Energies, UAB Campus, 08193 Bellaterra (Spain); Blanchot, G. [IFAE - Institut de Fisica d' Altes Energies, UAB Campus, 08193 Bellaterra (Spain); Chmeissani, M. [IFAE - Institut de Fisica d' Altes Energies, UAB Campus, 08193 Bellaterra (Spain); Garcia, J. [IFAE - Institut de Fisica d' Altes Energies, UAB Campus, 08193 Bellaterra (Spain); Lozano, M. [Centro Nacional de Microelectronica, IMB-CNM (CSIC), Barcelona 08193 (Spain); Martinez, R. [Centro Nacional de Microelectronica, IMB-CNM (CSIC), Barcelona 08193 (Spain); Puigdengoles, C. [IFAE - Institut de Fisica d' Altes Energies, UAB Campus, 08193 Bellaterra (Spain); Ullan, M. [Centro Nacional de Microelectronica, IMB-CNM (CSIC), Barcelona 08193 (Spain)

    2007-04-01

    In photon-counting imaging devices, charge sharing can limit the detector spatial resolution and contrast, as multiple counts can be induced in adjacent pixels as a result of the spread of the charge cloud generated from a single X-ray photon of high energy in the detector bulk. Although debated for a long time, the full impact of charge sharing has not been completely assessed. In this work, the importance of charge sharing in pixellated CdTe and silicon detectors is studied by exposing imaging devices to different low activity sources. These devices are made of Si and CdTe pixel detector bump-bonded to Medipix2 single-photon-counting chips with a 55 {mu}m pixel pitch. We will show how charge sharing affects the spatial detector resolution depending on incident particle type (alpha, beta and gamma), detector bias voltage and read-out chip threshold. This study will give an insight on the impact on the design and operation of pixel detectors coupled to photon-counting devices for imaging applications.

  10. Direct charge sharing observation in single-photon-counting pixel detector

    Science.gov (United States)

    Pellegrini, G.; Maiorino, M.; Blanchot, G.; Chmeissani, M.; Garcia, J.; Lozano, M.; Martinez, R.; Puigdengoles, C.; Ullan, M.

    2007-04-01

    In photon-counting imaging devices, charge sharing can limit the detector spatial resolution and contrast, as multiple counts can be induced in adjacent pixels as a result of the spread of the charge cloud generated from a single X-ray photon of high energy in the detector bulk. Although debated for a long time, the full impact of charge sharing has not been completely assessed. In this work, the importance of charge sharing in pixellated CdTe and silicon detectors is studied by exposing imaging devices to different low activity sources. These devices are made of Si and CdTe pixel detector bump-bonded to Medipix2 single-photon-counting chips with a 55 μm pixel pitch. We will show how charge sharing affects the spatial detector resolution depending on incident particle type (alpha, beta and gamma), detector bias voltage and read-out chip threshold. This study will give an insight on the impact on the design and operation of pixel detectors coupled to photon-counting devices for imaging applications.

  11. Operational performance and status of the ATLAS pixel detector at the LHC

    CERN Document Server

    Ince, T; The ATLAS collaboration

    2013-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC and its status after three years of operation will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The record breaking instantaneous luminosities of 7.7 x 10^33 cm-2 s-1 recently surpassed at the Large Hadron Collider generate a rapidly increasing particle fluence in the ATLAS Pixel Detector. As the radiation dose accumulates, the first effects of radiation damage are now observable in the silicon sensors. A regular monitoring program has been conducted and reveals an increase in the silicon leakage ...

  12. Status and future of the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Rozanov, A; The ATLAS collaboration

    2013-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC and its status after three years of operation will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The record breaking instantaneous luminosities of 7.7 x 10^33 cm-2 s-1 recently surpassed at the Large Hadron Collider generate a rapidly increasing particle fluence in the ATLAS Pixel Detector. As the radiation dose accumulates, the first effects of radiation damage are now observable in the silicon sensors. A regular monitoring program has been conducted and reveals an increase in the silicon leakage ...

  13. Operational Performance and Status of the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Jentzsch, J; The ATLAS collaboration

    2013-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC and its status after three years of operation will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The record breaking instantaneous luminosities of 7.7 x 10^33 cm-2 s-1 recently surpassed at the Large Hadron Collider generate a rapidly increasing particle fluence in the ATLAS Pixel Detector. As the radiation dose accumulates, the first effects of radiation damage are now observable in the silicon sensors. A regular monitoring program has been conducted and reveals an increase in the silicon leakage ...

  14. Operational Performance and Status of the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Jentzsch, J; The ATLAS collaboration

    2014-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experi- ment at the Large Hadron Collider at CERN. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individu- ally read out via chips bump-bonded to 1744 n+-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC and its status after three years of operation will be presented, including moni- toring, calibration procedures, timing optimization and detector performance. The record breaking instantaneous luminosities of 7.7 · 1033 cm−2s−1 recently surpassed at the Large Hadron Collider generate a rapidly increasing particle fluence in the ATLAS Pixel Detector. As the radiation dose accumulates, the first effects of radiation damage are now observable in the silicon sensors. A regular monitoring program has been conducted and reveals an increase in the silico...

  15. New pixelized Micromegas detector with low discharge rate for the COMPASS experiment

    CERN Document Server

    Neyret, D.; Anfreville, M.; Bedfer, Y.; Burtin, E.; Coquelet, C.; d'Hose, N.; Desforge, D.; Giganon, A.; Jourde, D.; Kunne, F.; Magnon, A.; Makke, N.; Marchand, C.; Paul, B.; Platchkov, S.; Thibaud, F.; Usseglio, M.; Vandenbroucke, M.

    2012-01-01

    New Micromegas (Micro-mesh gaseous detectors) are being developed in view of the future physics projects planned by the COMPASS collaboration at CERN. Several major upgrades compared to present detectors are being studied: detectors standing five times higher luminosity with hadron beams, detection of beam particles (flux up to a few hundred of kHz/mm^{2}, 10 times larger than for the present Micromegas detectors) with pixelized read-out in the central part, light and integrated electronics, and improved robustness. Two solutions of reduction of discharge impact have been studied, with Micromegas detectors using resistive layers and using an additional GEM foil. Performance of such detectors has also been measured. A large size prototypes with nominal active area and pixelized read-out has been produced and installed at COMPASS in 2010. In 2011 prototypes featuring an additional GEM foil, as well as an resistive prototype, are installed at COMPASS and preliminary results from those detectors presented very go...

  16. ProtoEXIST: Advanced Prototype CZT Coded Aperture Telescopes for EXIST

    CERN Document Server

    Allen, Branden; Grindlay, Josh; Barthelmy, Scott D; Baker, Robert G; Gehrels, Neil A; Garson, Trey; Krawwczynski, Henric S; Cook, Walter R; Harrison, Fiona A; Apple, Jeffery A; Ramsey, Brian D; 10.1117/12.857940

    2010-01-01

    {\\it ProtoEXIST1} is a pathfinder for the {\\it EXIST-HET}, a coded aperture hard X-ray telescope with a 4.5 m$^2$ CZT detector plane a 90$\\times$70 degree field of view to be flown as the primary instrument on the {\\it EXIST} mission and is intended to monitor the full sky every 3 h in an effort to locate GRBs and other high energy transients. {\\it ProtoEXIST1} consists of a 256 cm$^2$ tiled CZT detector plane containing 4096 pixels composed of an 8$\\times$8 array of individual 1.95 cm $\\times$ 1.95 cm $\\times$ 0.5 cm CZT detector modules each with a 8 $\\times$ 8 pixilated anode configured as a coded aperture telescope with a fully coded $10^\\circ\\times10^\\circ$ field of view employing passive side shielding and an active CsI anti-coincidence rear shield, recently completed its maiden flight out of Ft. Sumner, NM on the 9th of October 2009. During the duration of its 6 hour flight on-board calibration of the detector plane was carried out utilizing a single tagged 198.8 nCi Am-241 source along with the simult...

  17. Neural network based cluster creation in the ATLAS silicon Pixel Detector

    CERN Document Server

    Andreazza, A; The ATLAS collaboration

    2013-01-01

    The read-out from individual pixels on planar semi-conductor sensors are grouped into clusters to reconstruct the location where a charged particle passed through the sensor. The resolution given by individual pixel sizes is significantly improved by using the information from the charge sharing between pixels. Such analog cluster creation techniques have been used by the ATLAS experiment for many years to obtain an excellent performance. However, in dense environments, such as those inside high-energy jets, clusters have an increased probability of merging the charge deposited by multiple particles. Recently, a neural network based algorithm which estimates both the cluster position and whether a cluster should be split has been developed for the ATLAS Pixel Detector. The algorithm significantly reduces ambiguities in the assignment of pixel detector measurement to tracks within jets and improves the position accuracy with respect to standard interpolation techniques by taking into account the 2-dimensional ...

  18. Neural network based cluster creation in the ATLAS silicon Pixel Detector

    CERN Document Server

    Perez Cavalcanti, T; The ATLAS collaboration

    2012-01-01

    The hit signals read out from pixels on planar semi-conductor sensors are grouped into clusters, to reconstruct the location where a charged particle passed through. The resolution of the individual pixel sizes can be improved significantly using the information from the cluster of adjacent pixels. Such analog cluster creation techniques have been used by the ATLAS experiment for many years giving an excellent performance. However, in dense environments, such as those inside high-energy jets, is likely that the charge deposited by two or more close-by tracks merges into one single cluster. A new pattern recognition algorithm based on neural network methods has been developed for the ATLAS Pixel Detector. This can identify the shared clusters, split them if necessary, and estimate the positions of all particles traversing the cluster. The algorithm significantly reduces ambiguities in the assignment of pixel detector measurements to tracks within jets, and improves the positional accuracy with respect to stand...

  19. ASICs in nanometer and 3D technologies for readout of hybrid pixel detectors

    Science.gov (United States)

    Maj, Piotr; Grybos, Pawel; Kmon, Piotr; Szczygiel, Robert

    2013-07-01

    Hybrid pixel detectors working in a single photon counting mode are very attractive solutions for material science and medical X-ray imaging applications. Readout electronics of these detectors has to match the geometry of pixel detectors with an area of readout channel of 100 μm × 100 μm (or even less) and very small power consumption (a few tens of μW). New solutions of readout ASICs are going into directions of better spatial resolutions, higher data throughput and more advanced functionality. We report on the design and measurement results of two pixel prototype ASICs in nanometer technology and 3D technology which offer fast signal processing, low noise performance and advanced functionality per single readout pixel cell.

  20. Module Production and Qualification for the Phase I Upgrade of the CMS Pixel Detector

    CERN Document Server

    AUTHOR|(CDS)2086689

    2015-01-01

    After consolidation of the LHC in 2013/14 its centre-of-mass energy will increase to 13TeV and the luminosity will reach $2 \\cdot 10^{34}\\, \\textnormal{cm}^{-2} \\textnormal{s}^{-1}$, which is twice the design luminosity. The latter will result in more simultaneous particle collisions, which would significantly increase the dead time of the current readout chip of the CMS pixel detector. Therefore the entire CMS pixel detector is replaced in 2016/17 and a new digital readout with larger buffers will be used to handle increasing pixel hit rates. An additional fourth barrel-layer provides more space points to improve track reconstruction. Half of the required modules for layer four is being produced at Karlsruhe Institute of Technology (KIT). This poster deals with the smallest discrete subunit of the pixel detector, the module and its assembly process. Moreover first production experience will be shown.

  1. The upgraded Pixel Detector of the ATLAS Experiment for Run2 at the Large Hadron Collider

    CERN Document Server

    Backhaus, Malte; The ATLAS collaboration

    2015-01-01

    Run-2 of the LHC will provide new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 at a radius of 3.3 cm between the existing Pixel Detector and a new smaller radius beam-pipe. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, two different silicon sensor technologies (planar and 3D) have been developed as well as a new read-out chip within CMOS 130nm technology and with larger area, smaller pixel size and faster readout capability. The new detector is the first large scale application of of 3D detectors and CMOS 130nm technology. An overview of the lessons learned during the IBL project will be presented, focusing on the challenges and highlighting the issues met during the productio...

  2. The Dosepix detector—an energy-resolving photon-counting pixel detector for spectrometric measurements

    CERN Document Server

    Zang, A; Ballabriga, R; Bisello, F; Campbell, M; Celi, J C; Fauler, A; Fiederle, M; Jensch, M; Kochanski, N; Llopart, X; Michel, N; Mollenhauer, U; Ritter, I; Tennert, F; Wölfel, S; Wong, W; Michel, T

    2015-01-01

    The Dosepix detector is a hybrid photon-counting pixel detector based on ideas of the Medipix and Timepix detector family. 1 mm thick cadmium telluride and 300 μm thick silicon were used as sensor material. The pixel matrix of the Dosepix consists of 16 x 16 square pixels with 12 rows of (200 μm)2 and 4 rows of (55 μm)2 sensitive area for the silicon sensor layer and 16 rows of pixels with 220 μm pixel pitch for CdTe. Besides digital energy integration and photon-counting mode, a novel concept of energy binning is included in the pixel electronics, allowing energy-resolved measurements in 16 energy bins within one acquisition. The possibilities of this detector concept range from applications in personal dosimetry and energy-resolved imaging to quality assurance of medical X-ray sources by analysis of the emitted photon spectrum. In this contribution the Dosepix detector, its response to X-rays as well as spectrum measurements with Si and CdTe sensor layer are presented. Furthermore, a first evaluation wa...

  3. High Dynamic Range Pixel Array Detector for Scanning Transmission Electron Microscopy.

    Science.gov (United States)

    Tate, Mark W; Purohit, Prafull; Chamberlain, Darol; Nguyen, Kayla X; Hovden, Robert; Chang, Celesta S; Deb, Pratiti; Turgut, Emrah; Heron, John T; Schlom, Darrell G; Ralph, Daniel C; Fuchs, Gregory D; Shanks, Katherine S; Philipp, Hugh T; Muller, David A; Gruner, Sol M

    2016-02-01

    We describe a hybrid pixel array detector (electron microscope pixel array detector, or EMPAD) adapted for use in electron microscope applications, especially as a universal detector for scanning transmission electron microscopy. The 128×128 pixel detector consists of a 500 µm thick silicon diode array bump-bonded pixel-by-pixel to an application-specific integrated circuit. The in-pixel circuitry provides a 1,000,000:1 dynamic range within a single frame, allowing the direct electron beam to be imaged while still maintaining single electron sensitivity. A 1.1 kHz framing rate enables rapid data collection and minimizes sample drift distortions while scanning. By capturing the entire unsaturated diffraction pattern in scanning mode, one can simultaneously capture bright field, dark field, and phase contrast information, as well as being able to analyze the full scattering distribution, allowing true center of mass imaging. The scattering is recorded on an absolute scale, so that information such as local sample thickness can be directly determined. This paper describes the detector architecture, data acquisition system, and preliminary results from experiments with 80-200 keV electron beams.

  4. Tracking performance of a single-crystal and a polycrystalline diamond pixel-detector

    Energy Technology Data Exchange (ETDEWEB)

    Menasce, D.; et al.

    2013-06-01

    We present a comparative characterization of the performance of a single-crystal and a polycrystalline diamond pixel-detector employing the standard CMS pixel readout chips. Measurements were carried out at the Fermilab Test Beam Facility, FTBF, using protons of momentum 120 GeV/c tracked by a high-resolution pixel telescope. Particular attention was directed to the study of the charge-collection, the charge-sharing among adjacent pixels and the achievable position resolution. The performance of the single-crystal detector was excellent and comparable to the best available silicon pixel-detectors. The measured average detection-efficiency was near unity, ε = 0.99860±0.00006, and the position-resolution for shared hits was about 6 μm. On the other hand, the performance of the polycrystalline detector was hampered by its lower charge collection distance and the readout chip threshold. A new readout chip, capable of operating at much lower threshold (around 1 ke$-$), would be required to fully exploit the potential performance of the polycrystalline diamond pixel-detector.

  5. The Pixel Detector of the ATLAS Experiment for LHC Run-2

    CERN Document Server

    Pernegger, H; The ATLAS collaboration

    2014-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. Furthermore, the physics performance will be improved through the reduction of pixel size while, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system have been adopted. An overview of the refurbishing of the Pixel Detector and of the IBL project as ...

  6. Commissioning of the upgraded ATLAS Pixel Detector for Run2 at LHC

    CERN Document Server

    ATLAS Pixel Collaboration; The ATLAS collaboration

    2015-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. Furthermore, the physics performance will be improved through the reduction of pixel size while, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system have been adopted. An overview of the refurbishing of the Pixel Detector and of the IBL project as ...

  7. The ATLAS Pixel Detector for Run II at the Large Hadron Collider

    CERN Document Server

    Marx, Marilyn; The ATLAS collaboration

    2014-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. Furthermore, the physics performance will be improved through the reduction of pixel size while, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system have been adopted. An overview of the refurbishing of the Pixel Detector and of the IBL project as ...

  8. X-ray Characterization of a Multichannel Smart-Pixel Array Detector

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Steve; Haji-Sheikh, Michael; Huntington, Andrew; Kline, David; Lee, Adam; Li, Yuelin; Rhee, Jehyuk; Tarpley, Mary; Walko, Donald A.; Westberg, Gregg; Williams, George; Zou, Haifeng; Landahl, Eric

    2016-01-01

    The Voxtel VX-798 is a prototype X-ray pixel array detector (PAD) featuring a silicon sensor photodiode array of 48 x 48 pixels, each 130 mu m x 130 mu m x 520 mu m thick, coupled to a CMOS readout application specific integrated circuit (ASIC). The first synchrotron X-ray characterization of this detector is presented, and its ability to selectively count individual X-rays within two independent arrival time windows, a programmable energy range, and localized to a single pixel is demonstrated. During our first trial run at Argonne National Laboratory's Advance Photon Source, the detector achieved a 60 ns gating time and 700 eV full width at half-maximum energy resolution in agreement with design parameters. Each pixel of the PAD holds two independent digital counters, and the discriminator for X-ray energy features both an upper and lower threshold to window the energy of interest discarding unwanted background. This smart-pixel technology allows energy and time resolution to be set and optimized in software. It is found that the detector linearity follows an isolated dead-time model, implying that megahertz count rates should be possible in each pixel. Measurement of the line and point spread functions showed negligible spatial blurring. When combined with the timing structure of the synchrotron storage ring, it is demonstrated that the area detector can perform both picosecond time-resolved X-ray diffraction and fluorescence spectroscopy measurements.

  9. Edge pixel response studies of edgeless silicon sensor technology for pixellated imaging detectors

    Science.gov (United States)

    Maneuski, D.; Bates, R.; Blue, A.; Buttar, C.; Doonan, K.; Eklund, L.; Gimenez, E. N.; Hynds, D.; Kachkanov, S.; Kalliopuska, J.; McMullen, T.; O'Shea, V.; Tartoni, N.; Plackett, R.; Vahanen, S.; Wraight, K.

    2015-03-01

    Silicon sensor technologies with reduced dead area at the sensor's perimeter are under development at a number of institutes. Several fabrication methods for sensors which are sensitive close to the physical edge of the device are under investigation utilising techniques such as active-edges, passivated edges and current-terminating rings. Such technologies offer the goal of a seamlessly tiled detection surface with minimum dead space between the individual modules. In order to quantify the performance of different geometries and different bulk and implant types, characterisation of several sensors fabricated using active-edge technology were performed at the B16 beam line of the Diamond Light Source. The sensors were fabricated by VTT and bump-bonded to Timepix ROICs. They were 100 and 200 μ m thick sensors, with the last pixel-to-edge distance of either 50 or 100 μ m. The sensors were fabricated as either n-on-n or n-on-p type devices. Using 15 keV monochromatic X-rays with a beam spot of 2.5 μ m, the performance at the outer edge and corners pixels of the sensors was evaluated at three bias voltages. The results indicate a significant change in the charge collection properties between the edge and 5th (up to 275 μ m) from edge pixel for the 200 μ m thick n-on-n sensor. The edge pixel performance of the 100 μ m thick n-on-p sensors is affected only for the last two pixels (up to 110 μ m) subject to biasing conditions. Imaging characteristics of all sensor types investigated are stable over time and the non-uniformities can be minimised by flat-field corrections. The results from the synchrotron tests combined with lab measurements are presented along with an explanation of the observed effects.

  10. Preliminary test of an imaging probe for nuclear medicine using hybrid pixel detectors

    CERN Document Server

    Bertolucci, Ennio; Mettivier, G; Montesi, M C; Russo, P

    2002-01-01

    We are investigating the feasibility of an intraoperative imaging probe for lymphoscintigraphy with Tc-99m tracer, for sentinel node radioguided surgery, using the Medipix series of hybrid detectors coupled to a collimator. These detectors are pixelated semiconductor detectors bump-bonded to the Medipix1 photon counting read-out chip (64x64 pixel, 170 mu m pitch) or to the Medipix2 chip (256x256 pixel, 55 mu m pitch), developed by the European Medipix collaboration. The pixel detector we plan to use in the final version of the probe is a semi-insulating GaAs detector or a 1-2 mm thick CdZnTe detector. For the preliminary tests presented here, we used 300-mu m thick silicon detectors, hybridized via bump-bonding to the Medipix1 chip. We used a tungsten parallel-hole collimator (7 mm thick, matrix array of 64x64 100 mu m circular holes with 170 mu m pitch), and a 22, 60 and 122 keV point-like (1 mm diameter) radioactive sources, placed at various distances from the detector. These tests were conducted in order ...

  11. Design of analog-to-digital converters for energy sensitive hybrid pixel detectors

    NARCIS (Netherlands)

    San Segundo Bello, David; Nauta, Bram; Visschers, Jan

    2001-01-01

    An important feature of hybrid semiconductor pixel detectors is the fact that detector and readout electronics are manufactured separately, allowing the use of industrial state-of-the-art CMOS processes to manufacture the readout electronics. As the feature size of these processes decreases, faster

  12. Operational Experience and Performance with the ATLAS Pixel detector with emphasis on radiation damage

    CERN Document Server

    Butti, Pierfrancesco; The ATLAS collaboration

    2017-01-01

    The tracking performance of the ATLAS detector relies critically on its 4-layer Pixel Detector, that has undergone significant hardware and software upgrades to meet the challenges imposed by the higher collision energy, pileup and luminosity that are being delivered by the Large Hadron Collider, with record breaking instantaneous luminosities of 1.3 x 10^34 cm-2 s-1 recently surpassed. The key status and performance metrics of the ATLAS Pixel Detector are summarised, and the operational experience and requirements to ensure optimum data quality and data taking efficiency are described, with special emphasis to radiation damage experience.

  13. Operational Experience and Performance with the ATLAS Pixel detector with emphasis on radiation damage

    CERN Document Server

    Garcia Pascual, Juan Antonio; The ATLAS collaboration

    2017-01-01

    The tracking performance of the ATLAS detector relies critically on its 4-layer Pixel Detector, that has undergone significant hardware and software upgrades to meet the challenges imposed by the higher collision energy, pileup and luminosity that are being delivered by the Large Hadron Collider, with record breaking instantaneous luminosities of 1.3 x 10$^{34}$ cm$^{-2}$ s$^{-1}$ recently surpassed. The key status and performance metrics of the ATLAS Pixel Detector are summarised, and the operational experience and requirements to ensure optimum data quality and data taking efficiency are described, with special emphasis to radiation damage experience.

  14. Evaluation of Compton gamma camera prototype based on pixelated CdTe detectors

    OpenAIRE

    Y Calderón; Chmeissani, M.; Kolstein, M.; De Lorenzo, G.

    2014-01-01

    A proposed Compton camera prototype based on pixelated CdTe is simulated and evaluated in order to establish its feasibility and expected performance in real laboratory tests. The system is based on module units containing a 2×4 array of square CdTe detectors of 10×10 mm2 area and 2 mm thickness. The detectors are pixelated and stacked forming a 3D detector with voxel sizes of 2 × 1 × 2 mm3. The camera performance is simulated with Geant4-based Architecture for Medicine-Oriented Simulations(G...

  15. Pixel architectures in a HV-CMOS process for the ATLAS inner detector upgrade

    Science.gov (United States)

    Degerli, Y.; Godiot, S.; Guilloux, F.; Hemperek, T.; Krüger, H.; Lachkar, M.; Liu, J.; Orsini, F.; Pangaud, P.; Rymaszewski, P.; Wang, T.

    2016-12-01

    In this paper, design details and simulation results of new pixel architectures designed in LFoundry 150 nm high voltage CMOS process in the framework of the ATLAS high luminosity inner detector upgrade are presented. These pixels can be connected to the FE-I4 readout chip via bump bonding or glue and some of them can also be tested without a readout chip. Negative high voltage is applied to the high resistivity (> 2 kΩ .cm) substrate in order to deplete the deep n-well charge collection diode, ensuring good charge collection and radiation tolerance. In these pixels, the front-end has been implemented inside the diode using both NMOS and PMOS transistors. The pixel pitch is 50 μm × 250 μm for all pixels. These pixels have been implemented in a demonstrator chip called LFCPIX.

  16. The pixel hybrid photon detectors for the LHCb-RICH project

    CERN Document Server

    Gys, Thierry

    2001-01-01

    This paper describes a hybrid photon detector with integrated silicon pixel readout to be used in the ring imaging Cherenkov detectors of the LHCb experiment. The photon detector is based on a cross-focussed image intensifier tube geometry where the image is de-magnified by a factor of 5. The anode consists of a silicon pixel array, bump-bonded to a binary readout chip with matching pixel electronics. The paper starts with the general specification of the baseline option. Followed by a summary of the main results achieved so far during the R&D phase. It concludes with a description of the remaining work towards the final photon detector. (17 refs).

  17. The Layer 1 / Layer 2 readout upgrade for the ATLAS Pixel Detector

    CERN Document Server

    Mullier, Geoffrey; The ATLAS collaboration

    2016-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of the Large Hadron Collider (LHC). The increase of instantaneous luminosity foreseen during the LHC Run 2, will lead to an increased detector occupancy that is expected to saturate the readout links of the outermost layers of the pixel detector: Layers 1 and 2. To ensure a smooth data taking under such conditions, the read out system of the recently installed fourth innermost pixel layer, the Insertable B-Layer, was modified to accomodate the needs of the older detector. The Layer 2 upgrade installation took place during the 2015 winter shutdown, with the Layer 1 installation scheduled for 2016. A report of the successful installation, together with the design of novel dedicated optical to electrical converters and the software and firmware updates will be presented.

  18. Operational experience with the CMS pixel detector in LHC Run II

    CERN Document Server

    Karancsi, Janos

    2016-01-01

    The CMS pixel detector was repaired successfully, calibrated and commissioned for the second run of Large Hadron Collider during the first long shutdown between 2013 and 2015. The replaced pixel modules were calibrated separately and show the expected behavior of an un-irradiated detector. In 2015, the system performed very well with an even improved spatial resolution compared to 2012. During this time, the operational team faced various challenges including the loss of a sector in one half shell which was only partially recovered. In 2016, the detector is expected to withstand instantaneous luminosities beyond the design limits and will need a combined effort of both online and offline teams in order to provide the high quality data that is required to reach the physics goals of CMS. We present the operational experience gained during the second run of the LHC and show the latest performance results of the CMS pixel detector.

  19. Calibration of the CMS Pixel Detector at the Large Hadron Collider

    CERN Document Server

    Vami, Tamas Almos

    2014-01-01

    The Compact Muon Solenoid (CMS) detector is one of two general-purpose detectors that reconstruct the products of high energy particle interactions at the Large Hadron Collider (LHC) at CERN. The silicon pixel detector is the innermost component of the CMS tracking system. It determines the trajectories of charged particles originating from the interaction region in three points with high resolution enabling precise momentum and impact parameter measurements in the tracker. The pixel detector is exposed to intense ionizing radiation generated by particle collisions in the LHC. This irradiation could result in temporary or permanent malfunctions of the sensors and could decrease the efficiency of the detector. We have developed procedures in order to correct for these effects. In this paper, we present the types of malfunctions and the offline calibration procedures. We will also show the efficiency and the resolution of the detector in 2012.

  20. Calibration of the CMS Pixel Detector at the Large Hadron Collider

    CERN Document Server

    Vami, Tamas Almos

    2015-01-01

    The Compact Muon Solenoid (CMS) detector is one of two general-purpose detectors that reconstruct the products of high energy particle interactions at the Large Hadron Collider (LHC) at CERN. The silicon pixel detector is the innermost component of the CMS tracking system. It determines the trajectories of charged particles originating from the interaction region in three points with high resolution enabling precise momentum and impact parameter measurements in the tracker. The pixel detector is exposed to intense ionizing radiation generated by particle collisions in the LHC. This irradiation could result in temporary or permanent malfunctions of the sensors and could decrease the efficiency of the detector. We have developed procedures in order to correct for these effects. In this paper, we present the types of malfunctions and the offline calibration procedures. We will also show the efficiency and the resolution of the detector in 2012.

  1. DEPFET active pixel detectors for a future linear $e^+e^-$ collider

    CERN Document Server

    Alonso, O; Dieguez, A; Dingfelder, J; Hemperek, T; Kishishita, T; Kleinohl, T; Koch, M; Krueger, H; Lemarenko, M; Luetticke, F; Marinas, C; Schnell, M; Wermes, N; Campbell, A; Ferber, T; Kleinwort, C; Niebuhr, C; Soloviev, Y; Steder, M; Volkenborn, R; Yaschenko, S; Fischer, P; Kreidl, C; Peric, I; Knopf, J; Ritzert, M; Curras, E; Lopez-Virto, A; Moya, D; Vila, I; Boronat, M; Esperante, D; Fuster, J; Garcia Garcia, I; Lacasta, C; Oyanguren, A; Ruiz, P; Timon, G; Vos, M; Gessler, T; Kuehn, W; Lange, S; Muenchow, D; Spruck, B; Frey, A; Geisler, C; Schwenker, B; Wilk, F; Barvich, T; Heck, M; Heindl, S; Lutz, O; Mueller, Th; Pulvermacher, C; Simonis, H.J; Weiler, T; Krausser, T; Lipsky, O; Rummel, S; Schieck, J; Schlueter, T; Ackermann, K; Andricek, L; Chekelian, V; Chobanova, V; Dalseno, J; Kiesling, C; Koffmane, C; Gioi, L.Li; Moll, A; Moser, H.G; Mueller, F; Nedelkovska, E; Ninkovic, J; Petrovics, S; Prothmann, K; Richter, R; Ritter, A; Ritter, M; Simon, F; Vanhoefer, P; Wassatsch, A; Dolezal, Z; Drasal, Z; Kodys, P; Kvasnicka, P; Scheirich, J

    2013-01-01

    The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 $\\mathrm{\\mathbf{\\mu m}}$. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling and services. In this paper the status of DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear $\\mathbf{e^+ e^-}$ collider.

  2. Hard x-ray response of pixellated CdZnTe detectors

    Science.gov (United States)

    Abbene, L.; Del Sordo, S.; Caroli, E.; Gerardi, G.; Raso, G.; Caccia, S.; Bertuccio, G.

    2009-06-01

    In recent years, the development of cadmium zinc telluride (CdZnTe) detectors for x-ray and gamma ray spectrometry has grown rapidly. The good room temperature performance and the high spatial resolution of pixellated CdZnTe detectors make them very attractive in space-borne x-ray astronomy, mainly as focal plane detectors for the new generation of hard x-ray focusing telescopes. In this work, we investigated on the spectroscopic performance of two pixellated CdZnTe detectors coupled with a custom low noise and low power readout application specific integrated circuit (ASIC). The detectors (10×10×1 and 10×10×2 mm3 single crystals) have an anode layout based on an array of 256 pixels with a geometric pitch of 0.5 mm. The ASIC, fabricated in 0.8 μm BiCMOS technology, is equipped with eight independent channels (preamplifier and shaper) and characterized by low power consumption (0.5 mW/channel) and low noise (150-500 electrons rms). The spectroscopic results point out the good energy resolution of both detectors at room temperature [5.8% full width at half maximum (FWHM) at 59.5 keV for the 1 mm thick detector; 5.5% FWHM at 59.5 keV for the 2 mm thick detector) and low tailing in the measured spectra, confirming the single charge carrier sensing properties of the CdZnTe detectors equipped with a pixellated anode layout. Temperature measurements show optimum performance of the system (detector and electronics) at T =10 °C and performance degradation at lower temperatures. The detectors and the ASIC were developed by our collaboration as two small focal plane detector prototypes for hard x-ray multilayer telescopes operating in the 20-70 keV energy range.

  3. SU-C-201-03: Coded Aperture Gamma-Ray Imaging Using Pixelated Semiconductor Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, S [Wayne State University, Detroit, MI (United States); Kaye, W; Jaworski, J [H3D, Inc., Ann Arbor, MI (United States); He, Z [University of Michigan, Ann Arbor, MI (United States)

    2015-06-15

    Purpose: Improved localization of gamma-ray emissions from radiotracers is essential to the progress of nuclear medicine. Polaris is a portable, room-temperature operated gamma-ray imaging spectrometer composed of two 3×3 arrays of thick CdZnTe (CZT) detectors, which detect gammas between 30keV and 3MeV with energy resolution of <1% FWHM at 662keV. Compton imaging is used to map out source distributions in 4-pi space; however, is only effective above 300keV where Compton scatter is dominant. This work extends imaging to photoelectric energies (<300keV) using coded aperture imaging (CAI), which is essential for localization of Tc-99m (140keV). Methods: CAI, similar to the pinhole camera, relies on an attenuating mask, with open/closed elements, placed between the source and position-sensitive detectors. Partial attenuation of the source results in a “shadow” or count distribution that closely matches a portion of the mask pattern. Ideally, each source direction corresponds to a unique count distribution. Using backprojection reconstruction, the source direction is determined within the field of view. The knowledge of 3D position of interaction results in improved image quality. Results: Using a single array of detectors, a coded aperture mask, and multiple Co-57 (122keV) point sources, image reconstruction is performed in real-time, on an event-by-event basis, resulting in images with an angular resolution of ∼6 degrees. Although material nonuniformities contribute to image degradation, the superposition of images from individual detectors results in improved SNR. CAI was integrated with Compton imaging for a seamless transition between energy regimes. Conclusion: For the first time, CAI has been applied to thick, 3D position sensitive CZT detectors. Real-time, combined CAI and Compton imaging is performed using two 3×3 detector arrays, resulting in a source distribution in space. This system has been commercialized by H3D, Inc. and is being acquired for

  4. Data acquisition at the front-end of the Mu3e pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Perrevoort, Ann-Kathrin [Physikalisches Institut, Universitaet Heidelberg (Germany); Collaboration: Mu3e-Collaboration

    2016-07-01

    The Mu3e experiment - searching for the lepton-flavour violating decay of the muon into three electrons at an unprecedented sensitivity of one in 10{sup 16} decays - is based on a pixel tracking detector. The sensors are High-Voltage Monolithic Active Pixel Sensors, a technology which allows for very fast and thin detectors, and thus is an ideal fit for Mu3e where the trajectories of low-momentum electrons at high rates are to be measured. The detector will consist of about 275 million pixels and will be operated at up to 10{sup 9} muon stops per second. Therefore, a fast and trigger-less data readout is required. The pixel sensors feature zero-suppressed data output via high-speed serial links. The data is then buffered and sorted by time on a FPGA on the front-end before being processed to the following readout stage. In this talk, the readout of the Mu3e pixel detector at the front-end is introduced. Furthermore, a first firmware implementation of this concept in a beam telescope consisting of the current pixel sensor prototype MuPix7 is presented.

  5. High Dynamic Range Pixel Array Detector for Scanning Transmission Electron Microscopy

    CERN Document Server

    Tate, Mark W; Chamberlain, Darol; Nguyen, Kayla X; Hovden, Robert M; Chang, Celesta S; Deb, Pratiti; Turgut, Emrah; Heron, John T; Schlom, Darrell G; Ralph, Daniel C; Fuchs, Gregory D; Shanks, Katherine S; Philipp, Hugh T; Muller, David A; Gruner, Sol M

    2015-01-01

    We describe a hybrid pixel array detector (EMPAD - electron microscope pixel array detector) adapted for use in electron microscope applications, especially as a universal detector for scanning transmission electron microscopy. The 128 x 128 pixel detector consists of a 500 um thick silicon diode array bump-bonded pixel-by-pixel to an application-specific integrated circuit (ASIC). The in-pixel circuitry provides a 1,000,000:1 dynamic range within a single frame, allowing the direct electron beam to be imaged while still maintaining single electron sensitivity. A 1.1 kHz framing rate enables rapid data collection and minimizes sample drift distortions while scanning. By capturing the entire unsaturated diffraction pattern in scanning mode, one can simultaneously capture bright field, dark field, and phase contrast information, as well as being able to analyze the full scattering distribution, allowing true center of mass imaging. The scattering is recorded on an absolute scale, so that information such as loc...

  6. The Pixel Detector of the ATLAS experiment for the Run2 at the Large Hadron Collider

    CERN Document Server

    INSPIRE-00237659

    2015-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. Furthermore, the physics performance will be improved through the reduction of pixel size while, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system have been adopted. An overview of the refurbishing of the Pixel Detect or and of the IBL project as...

  7. High-speed X-ray imaging pixel array detector for synchrotron bunch isolation

    Energy Technology Data Exchange (ETDEWEB)

    Philipp, Hugh T., E-mail: htp2@cornell.edu; Tate, Mark W.; Purohit, Prafull; Shanks, Katherine S.; Weiss, Joel T. [Cornell University, Ithaca, NY 14853 (United States); Gruner, Sol M. [Cornell University, Ithaca, NY 14853 (United States); Cornell University, Ithaca, NY 14853 (United States)

    2016-01-28

    A high-speed pixel array detector for time-resolved X-ray imaging at synchrotrons has been developed. The ability to isolate single synchrotron bunches makes it ideal for time-resolved dynamical studies. A wide-dynamic-range imaging X-ray detector designed for recording successive frames at rates up to 10 MHz is described. X-ray imaging with frame rates of up to 6.5 MHz have been experimentally verified. The pixel design allows for up to 8–12 frames to be stored internally at high speed before readout, which occurs at a 1 kHz frame rate. An additional mode of operation allows the integration capacitors to be re-addressed repeatedly before readout which can enhance the signal-to-noise ratio of cyclical processes. This detector, along with modern storage ring sources which provide short (10–100 ps) and intense X-ray pulses at megahertz rates, opens new avenues for the study of rapid structural changes in materials. The detector consists of hybridized modules, each of which is comprised of a 500 µm-thick silicon X-ray sensor solder bump-bonded, pixel by pixel, to an application-specific integrated circuit. The format of each module is 128 × 128 pixels with a pixel pitch of 150 µm. In the prototype detector described here, the three-side buttable modules are tiled in a 3 × 2 array with a full format of 256 × 384 pixels. The characteristics, operation, testing and application of the detector are detailed.

  8. Leakage current measurements of a pixelated polycrystalline CVD diamond detector

    OpenAIRE

    Zain, R.M.; Maneuski, D.; O'Shea, V.; Bates, R.; Blue, A.; Cunnigham, L.; Stehl, C.; Berderman, E.; Rahim, R. A.

    2013-01-01

    Diamond has several desirable features when used as a material for radiation detection. With the invention of synthetic growth techniques, it has become feasible to look at developing diamond radiation detectors with reasonable surface areas. Polycrystalline diamond has been grown using a chemical vapour deposition (CVD) technique by the University of Augsburg and detector structures fabricated at the James Watt Nanofabrication Centre (JWNC) in the University of Glasgow in order to produce pi...

  9. The upgraded Pixel Detector of the ATLAS Experiment for Run2 at the Large Hadron Collider

    CERN Document Server

    Backhaus, Malte; The ATLAS collaboration

    2015-01-01

    During Run-1 of the Large Hadron Collider (LHC), the ATLAS Pixel Detector has shown excellent performance. The ATLAS collaboration took advantage of the first long shutdown of the LHC during 2013 and 2014 and extracted the ATLAS Pixel Detector from the experiment, brought it to surface and maintained the services. This includes the installation of new service quarter panels, the repair of cables, and the installation of the new Diamond Beam Monitor (DBM). Additionally a completely new innermost pixel detector layer, the Insertable B-Layer (IBL), was constructed and installed in May 2014 between a new smaller beam pipe and the existing Pixel Detector. With a radius of 3.3 cm the IBL is located extremely close to the interaction point. Therefore a new readout chip and two new sensor technologies (planar and 3D) are used in IBL. In order to achieve best possible physics performance the material budget was improved with respect to the existing Pixel Detector. This is realized using lightweight staves for mechanic...

  10. The upgraded Pixel Detector of the ATLAS Experiment for Run 2 at the Large Hadron Collider

    CERN Document Server

    Backhaus, M

    2016-01-01

    During Run 1 of the Large Hadron Collider (LHC), the ATLAS Pixel Detector has shown excellent performance. The ATLAS collaboration took advantage of the first long shutdown of the LHC during 2013 and 2014 and extracted the ATLAS Pixel Detector from the experiment, brought it to surface and maintained the services. This included the installation of new service quarter panels, the repair of cables, and the installation of the new Diamond Beam Monitor (DBM). Additionally, a completely new innermost pixel detector layer, the Insertable B-Layer (IBL), was constructed and installed in May 2014 between a new smaller beam pipe and the existing Pixel Detector. With a radius of 3.3 cm the IBL is located extremely close to the interaction point. Therefore, a new readout chip and two new sensor technologies (planar and 3D) are used in the IBL. In order to achieve best possible physics performance the material budget was improved with respect to the existing Pixel Detector. This is realized using lightweight staves for me...

  11. A new generation of small pixel pitch/SWaP cooled infrared detectors

    Science.gov (United States)

    Espuno, L.; Pacaud, O.; Reibel, Y.; Rubaldo, L.; Kerlain, A.; Péré-Laperne, N.; Dariel, A.; Roumegoux, J.; Brunner, A.; Kessler, A.; Gravrand, O.; Castelein, P.

    2015-10-01

    Following clear technological trends, the cooled IR detectors market is now in demand for smaller, more efficient and higher performance products. This demand pushes products developments towards constant innovations on detectors, read-out circuits, proximity electronics boards, and coolers. Sofradir was first to show a 10μm focal plane array (FPA) at DSS 2012, and announced the DAPHNIS 10μm product line back in 2014. This pixel pitch is a key enabler for infrared detectors with increased resolution. Sofradir recently achieved outstanding products demonstrations at this pixel pitch, which clearly demonstrate the benefits of adopting 10μm pixel pitch focal plane array-based detectors. Both HD and XGA Daphnis 10μm products also benefit from a global video datapath efficiency improvement by transitioning to digital video interfaces. Moreover, innovative smart pixels functionalities drastically increase product versatility. In addition to this strong push towards a higher pixels density, Sofradir acknowledges the need for smaller and lower power cooled infrared detector. Together with straightforward system interfaces and better overall performances, latest technological advances on SWAP-C (Size, Weight, Power and Cost) Sofradir products enable the advent of a new generation of high performance portable and agile systems (handheld thermal imagers, unmanned aerial vehicles, light gimbals etc...). This paper focuses on those features and performances that can make an actual difference in the field.

  12. The Pixel Detector of the ATLAS Experiment for LHC Run-2

    CERN Document Server

    Pernegger, Heinz; The ATLAS collaboration

    2015-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long shutdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and hit occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. Furthermore, the physics performance will be improved through the reduction of pixel size while, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system have been adopted. An overview of the refurbishing of the Pixel Detector and of the IBL project as we...

  13. Development of DC-DC converters for the upgrade of the CMS pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Feld, Lutz; Karpinski, Waclaw; Klein, Katja; Sammet, Jan; Wlochal, Michael [RWTH Aachen University (Germany)

    2012-07-01

    Around 2017, the pixel detector of the CMS experiment at LHC will be upgraded. The amount of current that has to be provided to the front-end electronics is expected to increase by a factor of two. Since the space available for cables is limited, this would imply unacceptable power losses in the available supply cables. Therefore it is foreseen to place DC-DC converters close to the front-end electronics, allowing to provide the power at higher voltages and thereby to facilitate the supply of the required currents with the present cable plant. The talk introduces the foreseen powering scheme of the pixel upgrade and summarizes the results of system test measurements with CMS pixel sensor modules, radiation tolerant DC-DC converters and the full power supply chain of the pixel detector. In addition, measurements of the converter efficiency and performance before, after and during thermal cycling are presented.

  14. Performance of silicon pixel detectors at small track incidence angles for the ATLAS Inner Tracker upgrade

    Science.gov (United States)

    Viel, Simon; Banerjee, Swagato; Brandt, Gerhard; Carney, Rebecca; Garcia-Sciveres, Maurice; Hard, Andrew Straiton; Kaplan, Laser Seymour; Kashif, Lashkar; Pranko, Aliaksandr; Rieger, Julia; Wolf, Julian; Wu, Sau Lan; Yang, Hongtao

    2016-09-01

    In order to enable the ATLAS experiment to successfully track charged particles produced in high-energy collisions at the High-Luminosity Large Hadron Collider, the current ATLAS Inner Detector will be replaced by the Inner Tracker (ITk), entirely composed of silicon pixel and strip detectors. An extension of the tracking coverage of the ITk to very forward pseudorapidity values is proposed, using pixel modules placed in a long cylindrical layer around the beam pipe. The measurement of long pixel clusters, detected when charged particles cross the silicon sensor at small incidence angles, has potential to significantly improve the tracking efficiency, fake track rejection, and resolution of the ITk in the very forward region. The performance of state-of-the-art pixel modules at small track incidence angles is studied using test beam data collected at SLAC and CERN.

  15. Pre- and post-irradiation performance of FBK 3D silicon pixel detectors for CMS

    Energy Technology Data Exchange (ETDEWEB)

    Krzywda, A., E-mail: akrzywda@purdue.edu [Purdue University, Department of Physics and Astronomy, West Lafayette, IN 47907-2036 (United States); Alagoz, E.; Bubna, M. [Purdue University, Department of Physics and Astronomy, West Lafayette, IN 47907-2036 (United States); Obertino, M. [Università del Piemonte Orientale, Novara (Italy); INFN, Sezione di Torino, Torino (Italy); Solano, A. [Università di Torino, Torino (Italy); INFN, Sezione di Torino, Torino (Italy); Arndt, K. [Purdue University, Department of Physics and Astronomy, West Lafayette, IN 47907-2036 (United States); Uplegger, L. [Fermi National Accelerator Laboratory, Batavia, IL 60510-5011 (United States); Betta, G.F. Dalla [TIFPA INFN and Dipartimento di Ingegneria Industriale, Università di Trento, Via Sommarive 9, I-38123 Povo di Trento, TN (Italy); Boscardin, M. [Centro per Materiali e i Microsistemi Fondazione Bruno Kessler (FBK), Trento, Via Sommarive 18, I-38123 Povo di Trento, TN (Italy); Ngadiuba, J. [Università di Milano-Bicocca, Milan (Italy); Rivera, R. [Fermi National Accelerator Laboratory, Batavia, IL 60510-5011 (United States); Menasce, D.; Moroni, L.; Terzo, S. [Università di Milano-Bicocca, Milan (Italy); Bortoletto, D. [Purdue University, Department of Physics and Astronomy, West Lafayette, IN 47907-2036 (United States); Prosser, A.; Adreson, J.; Kwan, S. [Fermi National Accelerator Laboratory, Batavia, IL 60510-5011 (United States); Osipenkov, I. [Texas A and M University, Department of Physics, College Station, TX 77843 (United States); Bolla, G. [Purdue University, Department of Physics and Astronomy, West Lafayette, IN 47907-2036 (United States); and others

    2014-11-01

    In preparation for the tenfold luminosity upgrade of the Large Hadron Collider (the HL-LHC) around 2020, three-dimensional (3D) silicon pixel sensors are being developed as a radiation-hard candidate to replace the planar ones currently being used in the CMS pixel detector. This study examines an early batch of FBK sensors (named ATLAS08) of three 3D pixel geometries: 1E, 2E, and 4E, which respectively contain one, two, and four readout electrodes for each pixel, passing completely through the bulk. We present electrical characteristics and beam test performance results for each detector before and after irradiation. The maximum fluence applied is 3.5×10{sup 15} n {sub eq}/cm{sup 2}.

  16. Performance of Silicon Pixel Detectors at Small Track Incidence Angles for the ATLAS Inner Tracker Upgrade

    CERN Document Server

    Viel, Simon; The ATLAS collaboration; Brandt, Gerhard; Carney, Rebecca; Garcia-Sciveres, Maurice; Hard, Andrew; Kaplan, Laser Seymour; Kashif, Lashkar; Pranko, Aliaksandr; Rieger, Julia; Wolf, Julian Choate; Wu, Sau Lan; Yang, Hongtao

    2015-01-01

    In order to enable the ATLAS experiment to successfully track charged particles produced in high-energy collisions at the High-Luminosity Large Hadron Collider, the current ATLAS Inner Detector will be replaced by the Inner Tracker (ITk), entirely composed of silicon pixel and strip detectors. An extension of the tracking coverage of the ITk to very forward pseudorapidity values is proposed, using pixel modules placed in a long cylindrical layer around the beam pipe. The measurement of long pixel clusters, detected when charged particles cross the silicon sensor at small incidence angles, has potential to significantly improve the tracking efficiency, fake track rejection, and resolution of the ITk in the very forward region. The performance of state-of-the-art pixel modules at small track incidence angles is studied using test beam data collected at SLAC and CERN.

  17. Imaging detector development for nuclear astrophysics using pixelated CdTe

    Science.gov (United States)

    Álvarez, J. M.; Gálvez, J. L.; Hernanz, M.; Isern, J.; Llopis, M.; Lozano, M.; Pellegrini, G.; Chmeissani, M.

    2010-11-01

    The concept of focusing telescopes in the energy range of lines of astrophysical interest (i.e., of energies around 1 MeV) should allow to reach unprecedented sensitivities, essential to perform detailed studies of cosmic explosions and cosmic accelerators. Our research and development activities aim to study a detector suited for the focal plane of a γ-ray telescope mission. A CdTe/CdZnTe detector operating at room temperature, that combines high detection efficiency with good spatial and spectral resolution is being studied in recent years as a focal plane detector, with the interesting option of also operating as a Compton telescope monitor. We present the current status of the design and development of a γ-ray imaging spectrometer in the MeV range, for nuclear astrophysics, consisting of a stack of CdTe pixel detectors with increasing thicknesses. We have developed an initial prototype based on CdTe ohmic detector. The detector has 11×11 pixels, with a pixel pitch of 1 mm and a thickness of 2 mm. Each pixel is stud bonded to a fanout board and routed to an front end ASIC to measure pulse height and rise time information for each incident γ-ray photon. First measurements of a 133Ba and 241Am source are reported here.

  18. Imaging detector development for nuclear astrophysics using pixelated CdTe

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, J.M., E-mail: alvarez@ieec.uab.e [Institut de Ciencies de l' Espai (CSIC-IEEC), Campus UAB, E-08193 Barcelona (Spain); Galvez, J.L.; Hernanz, M.; Isern, J.; Llopis, M. [Institut de Ciencies de l' Espai (CSIC-IEEC), Campus UAB, E-08193 Barcelona (Spain); Lozano, M.; Pellegrini, G. [Centro Nacional de Microelectronica - IMB-CNM (CSIC), Campus UAB, E-08193 Barcelona (Spain); Chmeissani, M. [Institut de Fisica d' Altes Energies (IFAE), Campus UAB, E-08193 Barcelona (Spain)

    2010-11-01

    The concept of focusing telescopes in the energy range of lines of astrophysical interest (i.e., of energies around 1 MeV) should allow to reach unprecedented sensitivities, essential to perform detailed studies of cosmic explosions and cosmic accelerators. Our research and development activities aim to study a detector suited for the focal plane of a {gamma}-ray telescope mission. A CdTe/CdZnTe detector operating at room temperature, that combines high detection efficiency with good spatial and spectral resolution is being studied in recent years as a focal plane detector, with the interesting option of also operating as a Compton telescope monitor. We present the current status of the design and development of a {gamma}-ray imaging spectrometer in the MeV range, for nuclear astrophysics, consisting of a stack of CdTe pixel detectors with increasing thicknesses. We have developed an initial prototype based on CdTe ohmic detector. The detector has 11x11 pixels, with a pixel pitch of 1 mm and a thickness of 2 mm. Each pixel is stud bonded to a fanout board and routed to an front end ASIC to measure pulse height and rise time information for each incident {gamma}-ray photon. First measurements of a {sup 133}Ba and {sup 241}Am source are reported here.

  19. The construction of the phase 1 upgrade of the CMS pixel detector

    CERN Document Server

    Weber, Hannsjorg Artur

    2017-01-01

    The innermost layers of the original CMS tracker were built out of pixel detectors arranged in three barrel layers and two forward disks in each endcap. The original CMS detector was designed for the nominal instantaneous LHC luminosity of $1\\times10^{34}\\,\\text{cm}^{-2}\\text{s}^{-1}$. Under the conditions expected in the coming years, which will see an increase of a factor two of the instantaneous luminosity, the CMS pixel detector would have seen a dynamic inefficiency caused by data losses due to buffer overflows. For this reason the CMS collaboration has installed during the recent extended end of year shutdown a replacement pixel detector. The phase-1 upgrade of the CMS pixel detector will operate at high efficiency at an instantaneous luminosity of $2\\times10^{34}\\,\\text{cm}^{-2}\\text{s}^{-1}$ with increased detector acceptance and additional redundancy for the tracking, while at the same time reducing the material budget. These goals are achieved using a new read-out chip and modified powering and rea...

  20. Performance verification of the CMS Phase 1 Upgrade pixel detector with collision data

    CERN Document Server

    Veszpremi, Viktor

    2017-01-01

    The CMS tracker consists of two tracking systems utilizing semiconductor technology: the inner pixel and the outer strip detectors. The tracker detectors occupy the volume around the beam interaction region between 3\\,cm and 110\\,cm in radius and up to 280\\,cm along the beam axis. The pixel detector consists of 124 million pixels, corresponding to about 2\\,m$^2$ total area. It plays a vital role in the seeding of the track reconstruction algorithms and in the reconstruction of primary interactions and secondary decay vertices. It is surrounded by the strip tracker with 10 million read-out channels, corresponding to 200\\,m$^2$ total area. The tracker is operated in a high-occupancy and high-radiation environment established by particle collisions in the LHC. The performance of the silicon strip detector continues to be of high quality. The pixel detector that has been used in Run 1 and in the first half of Run 2 was, however, replaced with the so-called Phase-1 Upgrade detector. The new system is better suite...

  1. \\title{Low-Cost Bump-Bonding Processes for High Energy Physics Pixel Detectors}

    CERN Document Server

    Caselle, Michele; Colombo, Fabio; Dierlamm, Alexander Hermann; Husemann, Ulrich; Kudella, Simon; Weber, M

    2015-01-01

    In the next generation of collider experiments detectors will be challenged by unprecedented particle fluxes. Thus large detector arrays of highly pixelated detectors with minimal dead area at reasonable costs are required. Bump-bonding of pixel detectors has been shown to be a major cost-driver. KIT is one of the production centers of the CMS barrel pixel detector for the Phase I Upgrade. In this contribution the SnPb bump-bonding process and the production yield is reported. In parallel to the production of the new CMS pixel detector, several alternatives to the expensive photolithography electroplating/electroless metal deposition technologies are developing. Recent progress and challenges faced in the development of bump-bonding technology based on gold-stud bonding by thin ($15\\,\\rm{\\mu m}$) gold wire is presented. This technique allows producing metal bumps with diameters down to $30\\,\\rm{\\mu m}$ without using photolithography processes, which are typically required to provide suitable under bu...

  2. The barrel sector assembly system of the ALICE silicon pixel detector

    CERN Document Server

    Antinori, F; Cinausero, M; Dima, R; Fabris, D; Fioretto, E; Lunardon, M; Moretto, S; Pepato, Adriano; Prete, G; Scarlassara, F; Segato, G F; Soramel, F; Turrisi, R; Vannucci, L; Viesti, G

    2004-01-01

    The Silicon Pixel Detector is the inner part of the ITS tracking system of the ALICE experiment at LHC. The 240 silicon modules, hosting almost 10 million pixel cells with dimension 50 . 425 mu m /sup 2/, have to be assembled on a carbon fiber support with micrometric precision. To reach this result, a dedicated high- precision computer-controlled tooling system has been developed at the INFN Padova. The assembly system and the mounting procedures are presented. (10 refs).

  3. Performance of the Insertable B-Layer for the ATLAS Pixel Detector during Quality Assurance and a Novel Pixel Detector Readout Concept based on PCIe

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00356268; Pernegger, Heinz

    2016-07-27

    During the first long shutdown of the LHC the Pixel detector has been upgraded with a new 4th innermost layer, the Insertable B-Layer (IBL). The IBL will increase the tracking performance and help with higher than nominal luminosity the LHC will produce. The IBL is made up of 14 staves and in total 20 staves have been produced for the IBL. This thesis presents the results of the final quality tests performed on these staves in an detector-like environment, in order to select the 14 best of the 20 staves for integration onto the detector. The test setup as well as the testing procedure is introduced and typical results of each testing stage are shown and discussed. The overall performance of all staves is presented in regards to: tuning performance, radioactive source measurements, and number of failing pixels. Other measurement, which did not directly impact the selection of staves, but will be important for the operation of the detector or production of a future detector, are included. Based on the experienc...

  4. Geneva University: Pixel Detectors – trends and options for the future

    CERN Multimedia

    Geneva University

    2012-01-01

    GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92   Wednesday 25 April 2012 SEMINAIRE DE PHYSIQUE CORPUSCULAIRE Science III, Auditoire 1S081 30Science III, Auditoire 1S081 30 Pixel Detectors – trends and options for the future Prof. Norbert Wermes - University of Bonn  Pixel detectors have been invented in the early 90s with the advancement of micro technologies. With the advent of the LHC, big vertex detectors have demonstrated that the pixel detector type is holding many of the promises it had made before. Meanwhile new, different or just improved variants of the pixel technology are being studied for their suitability for future experiments or experiment upgrades. The talk will address the various pro's and con's comparing hybrid and monolithic pixel technologies and their su...

  5. The upgraded Pixel Detector of the ATLAS Experiment for Run2 at the Large Hadron Collider

    CERN Document Server

    Mullier, Geoffrey Andre; The ATLAS collaboration

    2015-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL), a fourth layer of pixel detectors, installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and increased pixel occupancy due to the proximity to the interaction point, two different silicon sensor technologies (planar and 3D) have been developed. A new readout chip has been developed within CMOS 130nm technology with larger area, smaller pixel size and faster readout capability. Dedicated design features in combination with a new composite material were considered and used in order to reduce the material budget of the support structure while keeping the optimal thermo-mechanical performan...

  6. The Pixel Detector of the ATLAS experiment for the Run 2 at the Large Hadron Collider

    CERN Document Server

    Oide, H; The ATLAS collaboration

    2014-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run 1 of LHC. Taking advantage of the long shutdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). The IBL is the fourth layer of the Run 2 Pixel Detector, and it was installed in May 2014 between the existing Pixel Detector and the new smaller-radius beam pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. Furthermore, the physics performance will be improved through the reduction of pixel size while, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system have been adopted. IBL construction is now completed. An overview of the IBL project...

  7. The Pixel Detector of the ATLAS experiment for the Run2 at the Large Hadron Collider

    CERN Document Server

    Mandelli, B; The ATLAS collaboration

    2014-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long shutdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and will be installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. Furthermore, the physics performance will be improved through the reduction of pixel size while, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system have been adopted. IBL construction is now completed. An overview of the IBL project as well as the ...

  8. The Pixel Detector of the ATLAS experiment for the Run2 at the Large Hadron Collider

    CERN Document Server

    Oide, H; The ATLAS collaboration

    2014-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and will be installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. Furthermore, the physics performance will be improved through the reduction of pixel size while, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system have been adopted. IBL construction is now completed. An overview of the IBL project as well as the ...

  9. A 2D smart pixel detector for time-resolved protein crystallography

    Energy Technology Data Exchange (ETDEWEB)

    Beuville, E.; Cork, C.; Earnest, T. [and others

    1995-10-01

    A smart pixel detector is being developed for Time Resolved Crystallography for biological and material science applications. Using the Pixel detector presented here, the Laue method will enable the study of the evolution of structural changes that occur within the protein as a function of time. The x-ray pixellated detector is assembled to the integrated circuit through a bump bonding process. Within a pixel size of 150 x 150 {mu}m{sup 2}, a low noise preamplifier-shaper, a discriminator, a 3 bit counter and the readout logic are integrated. The readout, based on the Column Architecture principle, will accept hit rates above 5x10{sup 8}/cm{sup 2}/s with a maximum hit rate per pixel of 1 MHz. This detector will allow time resolved Laue crystallography to be performed in a frameless operation mode, without dead time. Target specifications, architecture, and preliminary results on the 8 x 8 front-end prototype and column readout are presented.

  10. Signal height in silicon pixel detectors irradiated with pions and protons

    CERN Document Server

    Rohe, T.; Bean, A.; Dambach, S.; Erdmann, W.; Langenegger, U.; Martin, C.; Meier, B.; Radicci, V.; Sibille, J.; Trub, P.

    2009-01-01

    Pixel detectors are used in the innermost part of multi purpose experiments at the Large Hadron Collider (LHC) and are therefore exposed to the highest fluences of ionising radiation, which in this part of the detectors consists mainly of charged pions. The radiation hardness of the detectors has thoroughly been tested up to the fluences expected at the LHC. In case of an LHC upgrade the fluence will be much higher and it is not yet clear up to which radii the present pixel technology can be used. In order to establish such a limit, pixel sensors of the size of one CMS pixel readout chip (PSI46V2.1) have been bump bonded and irradiated with positive pions up to 6E14 Neq/cm^2 at PSI and with protons up to 5E15 Neq/cm^2. The sensors were taken from production wafers of the CMS barrel pixel detector. They use n-type DOFZ material with a resistance of about 3.7kOhm cm and an n-side read out. As the performance of silicon sensors is limited by trapping, the response to a Sr-90 source was investigated. The highly e...

  11. Beam test characterization of CMS silicon pixel detectors for the phase-1 upgrade

    Science.gov (United States)

    Korol, I.

    2015-10-01

    The Silicon Pixel Detector forms the innermost part of the CMS tracking system and is critical to track and vertex reconstruction. Being in close proximity to the beam interaction point, it is exposed to the highest radiation levels in the silicon tracker. In order to preserve the tracking performance with the LHC luminosity increase which is foreseen for the next years, the CMS collaboration has decided to build a new pixel detector with four barrel layers mounted around a reduced diameter beam pipe, as compared to the present three layer pixel detector in the central region. A new digital version of the front-end readout chip has been designed and tested; it has increased data buffering and readout link speed to maintain high efficiency at increasing occupancy. In addition, it offers lower charge thresholds that will improve the tracking efficiency and position resolution. Single chip modules have been evaluated in the DESY electron test beam in terms of charge collection, noise, tracking efficiency and position resolution before and after irradiation with 24 GeV protons from the CERN Proton Synchroton equivalent to the fluence expected after 500 fb-1 of integrated luminosity in the fourth layer of the pixel tracker. High efficiency and an excellent position resolution have been observed which are well maintained even after the proton irradiation. The results are well described by the CMS pixel detector simulation.

  12. Performance of silicon pixel detectors at small track incidence angles for the ATLAS Inner Tracker upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Viel, Simon, E-mail: sviel@lbl.gov [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Banerjee, Swagato [Department of Physics, University of Wisconsin, Madison, WI, United States of America (United States); Brandt, Gerhard; Carney, Rebecca; Garcia-Sciveres, Maurice [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Hard, Andrew Straiton; Kaplan, Laser Seymour; Kashif, Lashkar [Department of Physics, University of Wisconsin, Madison, WI, United States of America (United States); Pranko, Aliaksandr [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Rieger, Julia [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); II Physikalisches Institut, Georg-August-Universität, Göttingen (Germany); Wolf, Julian [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Wu, Sau Lan; Yang, Hongtao [Department of Physics, University of Wisconsin, Madison, WI, United States of America (United States)

    2016-09-21

    In order to enable the ATLAS experiment to successfully track charged particles produced in high-energy collisions at the High-Luminosity Large Hadron Collider, the current ATLAS Inner Detector will be replaced by the Inner Tracker (ITk), entirely composed of silicon pixel and strip detectors. An extension of the tracking coverage of the ITk to very forward pseudorapidity values is proposed, using pixel modules placed in a long cylindrical layer around the beam pipe. The measurement of long pixel clusters, detected when charged particles cross the silicon sensor at small incidence angles, has potential to significantly improve the tracking efficiency, fake track rejection, and resolution of the ITk in the very forward region. The performance of state-of-the-art pixel modules at small track incidence angles is studied using test beam data collected at SLAC and CERN. - Highlights: • Extended inner pixel barrel layers are proposed for the ATLAS ITk upgrade. • Test beam results at small track incidence angles validate this ATLAS ITk design. • Long pixel clusters are reconstructed with high efficiency at low threshold values. • Excellent angular resolution is achieved using pixel cluster length information.

  13. Design of a 12-bit 1 MS/s SAR-ADC for front-end readout of 32-channel CZT detector imaging system

    Science.gov (United States)

    Liu, Wei; Wei, Tingcun; Li, Bo; Guo, Panjie; Hu, Yongcai

    2015-06-01

    A 12-bit 1MS/s SAR-ADC for the front-end readout of a 32-channel CZT detector imaging system is presented. In order to improve the performances of the ADC, several techniques are proposed. First, a novel offset cancellation method for comparator is proposed, in which no any capacitor is introduced in the signal pathway, thus it has faster operation speed than traditional one. Second, the architecture of unit capacitor array is adopted in the charge-redistribution DAC to reduce the capacitor mismatch. Third, the radiation-hardened ability is enhanced through circuit and layout design. The prototype chip was fabricated using a TSMC 0.35 um 2P4M CMOS process. At a 3.3/5 V power supply, the proposed SAR-ADC achieves 67.64 dB SINAD at 1MS/s, consumes 10 mW power and occupies a core area of 1180×1080 um2.

  14. Design of a 12-bit 1 MS/s SAR-ADC for front-end readout of 32-channel CZT detector imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wei, E-mail: liouwei930@sina.com [School of Computer Science and Technology, Northwestern Polytechnical University, Xi' an 710072, Shaanxi (China); Wei, Tingcun; Li, Bo; Guo, Panjie [School of Computer Science and Technology, Northwestern Polytechnical University, Xi' an 710072, Shaanxi (China); Hu, Yongcai [Institut Pluridisciplinaire Hubert CURIEN, Strasbourg (France)

    2015-06-21

    A 12-bit 1MS/s SAR-ADC for the front-end readout of a 32-channel CZT detector imaging system is presented. In order to improve the performances of the ADC, several techniques are proposed. First, a novel offset cancellation method for comparator is proposed, in which no any capacitor is introduced in the signal pathway, thus it has faster operation speed than traditional one. Second, the architecture of unit capacitor array is adopted in the charge-redistribution DAC to reduce the capacitor mismatch. Third, the radiation-hardened ability is enhanced through circuit and layout design. The prototype chip was fabricated using a TSMC 0.35 um 2P4M CMOS process. At a 3.3/5 V power supply, the proposed SAR-ADC achieves 67.64 dB SINAD at 1MS/s, consumes 10 mW power and occupies a core area of 1180×1080 um{sup 2}.

  15. Assembly procedure of the module (half-stave) of the ALICE Silicon Pixel Detector

    CERN Document Server

    Caselle, M; Antinori, F; Burns, M; Campbell, M; Chochula, P; Dinapoli, R; Elia, D; Formenti, F; Fini, R A; Ghidini, B; Kluge, A; Lenti, V; Manzari, V; Meddi, F; Morel, M; Navach, F; Nilsson, P; Pepato, Adriano; Riedler, P; Santoro, R; Stefanini, G; Viesti, G; Wyllie, K

    2004-01-01

    The Silicon Pixel Detector (SPD) forms the two innermost layers of the ALICE Inner Tracking System (ITS). The detector includes 1200 readout ASICs, each containing 8192 pixel cells, bump-bonded to Si sensor elements. The thickness of the readout chip and the sensor element is 150mum and 200mum, respectively. Low-mass solutions are implemented for the bus and the mechanical support. In this contribution, we describe the basic module (half-stave) of the two SPD layers and we give an overview of its assembly procedure.

  16. Compressive spectral polarization imaging by a pixelized polarizer and colored patterned detector.

    Science.gov (United States)

    Fu, Chen; Arguello, Henry; Sadler, Brian M; Arce, Gonzalo R

    2015-11-01

    A compressive spectral and polarization imager based on a pixelized polarizer and colored patterned detector is presented. The proposed imager captures several dispersed compressive projections with spectral and polarization coding. Stokes parameter images at several wavelengths are reconstructed directly from 2D projections. Employing a pixelized polarizer and colored patterned detector enables compressive sensing over spatial, spectral, and polarization domains, reducing the total number of measurements. Compressive sensing codes are specially designed to enhance the peak signal-to-noise ratio in the reconstructed images. Experiments validate the architecture and reconstruction algorithms.

  17. Gamma spectroscopic measurements using the PID350 pixelated CdTe radiation detector

    CERN Document Server

    Karafasoulis, K; Seferlis, S; Papadakis, I; Loukas, D; Lambropoulos, C; Potiriadis, C

    2010-01-01

    Spectroscopic measurements are presented using the PID350 pixelated gamma radiation detectors. A high-speed data acquisition system has been developed in order to reduce the data loss during the data reading in case of a high flux of photons. A data analysis framework has been developed in order to improve the resolution of the acquired energy spectra, using specific calibration parameters for each PID350's pixel. Three PID350 detectors have been used to construct a stacked prototype system and spectroscopic measurements have been performed in order to test the ability of the prototype to localize radioactive sources.

  18. A Leakage Current-based Measurement of the Radiation Damage in the ATLAS Pixel Detector

    CERN Document Server

    Gorelov, Igor; The ATLAS collaboration

    2015-01-01

    A measurement has been made of the radiation damage incurred by the ATLAS Pixel Detector barrel silicon modules from the beginning of operations through the end of 2012. This translates to hadronic fluence received over the full period of operation at energies up to and including 8 TeV. The measurement is based on a per-module measurement of the silicon sensor leakage current. The results are presented as a function of integrated luminosity and compared to predictions by the Hamburg Model. This information can be used to predict limits on the lifetime of the Pixel Detector due to current, for various operating scenarios.

  19. Versatile, reprogrammable area pixel array detector for time-resolved synchrotron x-ray applications

    Energy Technology Data Exchange (ETDEWEB)

    Gruner, Sol [Cornell Univ., Ithaca, NY (United States)

    2010-05-01

    The final technical report for DOE grant DE-SC0004079 is presented. The goal of the grant was to perform research, development and application of novel imaging x-ray detectors so as to effectively utilize the high intensity and brightness of the national synchrotron radiation facilities to enable previously unfeasible time-resolved x-ray research. The report summarizes the development of the resultant imaging x-ray detectors. Two types of detector platforms were developed: The first is a detector platform (called a Mixed-Mode Pixel Array Detector, or MM-PAD) that can image continuously at over a thousand images per second while maintaining high efficiency for wide dynamic range signals ranging from 1 to hundreds of millions of x-rays per pixel per image. Research on an even higher dynamic range variant is also described. The second detector platform (called the Keck Pixel Array Detector) is capable of acquiring a burst of x-ray images at a rate of millions of images per second.

  20. 3D silicon pixel detectors for the High-Luminosity LHC

    CERN Document Server

    Lange, J.

    2016-01-01

    3D silicon pixel detectors have been investigated as radiation-hard candidates for the innermost layers of the HL-LHC upgrade of the ATLAS pixel detector. 3D detectors are already in use today in the ATLAS IBL and AFP experiments. These are based on 50x250 um2 large pixels connected to the FE-I4 readout chip. Detectors of this generation were irradiated to HL-LHC fluences and demonstrated excellent radiation hardness with operational voltages as low as 180 V and power dissipation of 12--15 mW/cm2 at a fluence of about 1e16 neq/cm2, measured at -25 degree C. Moreover, to cope with the higher occupancies expected at the HL-LHC, a first run of a new generation of 3D detectors designed for the HL-LHC was produced at CNM with small pixel sizes of 50x50 and 25x100 um2, matched to the FE-I4 chip. They demonstrated a good performance in the laboratory and in beam tests with hit efficiencies of about 97% at already 1--2V before irradiation.

  1. Testing and Integration of the Service Cylinders for the CMS Phase 1 pixel detector

    CERN Document Server

    Ngadiuba, Jennifer

    2016-01-01

    The present 3-layer CMS pixel detector will be replaced with a new 4-layer pixel system, referred to as Phase~1 upgrade, during the LHC extended technical stop in winter 2016/2017. The upgraded detector will allow to maintain the excellent tracking performance of CMS at the upcoming higher luminosity conditions at the LHC. The addition of an extra layer, closer to the beam pipe, demands a complete redesign of its services. The barrel pixel detector is attached to four half cylinders which carry the services along the beam pipe, accommodate the cooling lines and house the electronics for detector readout and control. The service cylinders are a complex system in design as well as in production due to the large number of channels and tight space requirements. In this document we present the design of the system and discuss the construction and testing of the service cylinders for the barrel pixel detector. Furthermore, we present results of the testing and calibrations carried out with a set of new digital dete...

  2. 3D silicon pixel detectors for the High-Luminosity LHC

    Science.gov (United States)

    Lange, J.; Carulla Areste, M.; Cavallaro, E.; Förster, F.; Grinstein, S.; López Paz, I.; Manna, M.; Pellegrini, G.; Quirion, D.; Terzo, S.; Vázquez Furelos, D.

    2016-11-01

    3D silicon pixel detectors have been investigated as radiation-hard candidates for the innermost layers of the HL-LHC upgrade of the ATLAS pixel detector. 3D detectors are already in use today in the ATLAS IBL and AFP experiments. These are based on 50 × 250 μm2 large pixels connected to the FE-I4 readout chip. Detectors of this generation were irradiated to HL-LHC fluences and demonstrated excellent radiation hardness with operational voltages as low as 180 V and power dissipation of 12-15 mW/cm2 at a fluence of about 1016 neq/cm2, measured at -25°C. Moreover, to cope with the higher occupancies expected at the HL-LHC, a first run of a new generation of 3D detectors designed for the HL-LHC was produced at CNM with small pixel sizes of 50 × 50 and 25 × 100 μm2, matched to the FE-I4 chip. They demonstrated a good performance in the laboratory and in beam tests with hit efficiencies of about 97% at already 1-2 V before irradiation.

  3. Pixel detectors for use in retina neurophysiology studies

    CERN Document Server

    Cunningham, W; Chichilnisky, E J; Horn, M; Litke, A M; Mathieson, K; McEwan, F A; Melone, J; O'Shea, V; Rahman, M; Smith, K M

    2003-01-01

    One area of major inter-disciplinary co-operation is between the particle physics and bio-medical communities. The type of large detector arrays and fast electronics developed in laboratories like CERN are becoming used for a wide range of medical and biological experiments. In the present work fabrication technology developed for producing semiconductor radiation detectors has been applied to produce arrays which have been used in neuro-physiological experiments on retinal tissue. We have exploited UVIII, a low molecular weight resist, that has permitted large area electron beam lithography. This allows the resolution to go below that of conventional photolithography and hence the production of densely packed similar to 500 electrode arrays with feature sizes down to below 2 mum. The neural signals from significant areas of the retina may thus be captured.

  4. Medipix3: A 64 k pixel detector readout chip working in single photon counting mode with improved spectrometric performance

    CERN Document Server

    Ballabriga, R; Wong, W; Heijne, E; Campbell, M; Llopart, X

    2011-01-01

    Medipix3 is a 256 x 256 channel hybrid pixel detector readout chip working in a single photon counting mode with a new inter-pixel architecture, which aims to improve the energy resolution in pixelated detectors by mitigating the effects of charge sharing between channels. Charges are summed in all 2 x 2 pixel clusters on the chip and a given hit is allocated locally to the pixel summing circuit with the biggest total charge on an event-by-event basis. Each pixel contains also two 12-bit binary counters with programmable depth and overflow control. The chip is configurable such that either the dimensions of each detector pixel match those of one readout pixel or detector pixels are four times greater in area than the readout pixels. In the latter case, event-by-event summing is still possible between the larger pixels. Each pixel has around 1600 transistors and the analog static power consumption is below 15 mu W in the charge summing mode and 9 mu W in the single pixel mode. The chip has been built in an 8-m...

  5. Design Optimization of Pixel Structure for α-Si based Uncooled Infrared Detector

    Directory of Open Access Journals (Sweden)

    Sudha Gupta

    2013-11-01

    Full Text Available In this paper authors present the design and simulation results achieved for pixel structure of amorphous Si (α-Si based bolometer array. Most uncooled IR detectors in the world are based on VOx material. But this is not a standard material in IC technology and has many inherent disadvantages. The α-Si, an alternative material with high TCR is becoming as popular. However, large TCR values, in this material are achieved only in films of high resistivity. To achieve TCR value more than 2.5%/K, α-Si film resistivity is ~ 80 ohms-cm. This gives rise to very large pixel resistance of the order of 100 Mega ohms depending upon the design of the leg structure. This high pixel resistance causes very large noise and hence lower sensitivity. If leg width or membrane thickness is increased in order to reduce the pixel resistance, then this results in higher thermal conductance which also decreases sensitivity. To overcome this problem, pixel structure is so designed that within a pixel, only part of the electrical conduction is through α-Si and rest is through metal. Simulation using Coventorware software has been done to optimize pixel resistance as well as thermal conductance through legs so that maximum sensitivity could be obtained. Optimization is also carried out in order to reduce sensitivity of pixel resistance to variation in material resistivity.

  6. Test of a fine pitch SOI pixel detector with laser beam

    CERN Document Server

    Liu, Yi; Ju, Xudong; Ouyang, Qun

    2015-01-01

    A fine pitch pixel detector, developed on SOI (Silicon on Insulator) technology, has been tested under the illumination of infrared laser pulses. As an alternative way beside particel beam test, the laser pulses are tuned to very short duration and small transverse profile to simulate tracks of MIPs (Minimum Ionization Particles) in silicon. Hit cluster size and substrate depletion characteristics of this SOI detector are obtained. When focused laser pulses propagate through SOI detector perpendicularly to its surface, the hit cluster is measured, and most of signal charges are collected directly by the seed pixel. The signal amplitude as a function of applied bias voltage has been measured on this SOI detector for the first time, which helps us better understand of depletion characteristics.

  7. Silicon micro-fluidic cooling for NA62 GTK pixel detectors

    CERN Document Server

    Romagnoli, G; Brunel, B; Catinaccio, A; Degrange, J; Mapelli, A; Morel, M; Noel, J; Petagna, P

    2015-01-01

    Silicon micro-channel cooling is being studied for efficient thermal management in application fields such as high power computing and 3D electronic integration. This concept has been introduced in 2010 for the thermal management of silicon pixel detectors in high energy physics experiments. Combining the versatility of standard micro-fabrication processes with the high thermal efficiency typical of micro-fluidics, it is possible to produce effective thermal management devices that are well adapted to different detector configurations. The production of very thin cooling devices in silicon enables a minimization of material of the tracking sensors and eliminates mechanical stresses due to the mismatch of the coefficient of thermal expansion between detectors and cooling systems. The NA62 experiment at CERN will be the first high particle physics experiment that will install a micro-cooling system to perform the thermal management of the three detection planes of its Gigatracker pixel detector.

  8. Studies for the detector control system of the ATLAS pixel at the HL-LHC

    CERN Document Server

    Püllen, L; Boek, J; Kersten, S; Kind, P; Mättig, P; Zeitnitz, C

    2012-01-01

    experiment will be replaced completely. As part of this redesign there will also be a new pixel detector. This new pixel detector requires a control system which meets the strict space requirements for electronics in the ATLAS experiment. To accomplish this goal we propose a DCS (Detector Control System) network with the smallest form factor currently available. This network consists of a DCS chip located in close proximity to the interaction point and a DCS controller located in the outer regions of the ATLAS detector. These two types of chips form a star shaped network with several DCS chips being controlled by one DCS controller. Both chips are manufactured in deep sub-micron technology. We present prototypes with emphasis on studies concerning single event upsets.

  9. An Interdigitated Pixel PIN Detector for Energetic Particle Spectroscopy in Space

    OpenAIRE

    1993-01-01

    We describe a new two-dimensional position-sensitive detector, now under development, for use in space-borne energetic particle spectrometers. The novel feature of this device is the use of interdigitated pixels to provide both dimensions of position information from a single side of the detector, while a measurement of the energy deposition is derived from the opposite side. An advantage of this approach is that significant reductions in the complexity, power, and weight of th...

  10. 3 mega-pixel InSb detector with 10μm pitch

    Science.gov (United States)

    Gershon, G.; Albo, A.; Eylon, M.; Cohen, O.; Calahorra, Z.; Brumer, M.; Nitzani, M.; Avnon, E.; Aghion, Y.; Kogan, I.; Ilan, E.; Shkedy, L.

    2013-06-01

    SCD has developed a new 1920x1536 / 10 μm digital Infrared detector for the MWIR window named Blackbird. The Blackbird detector features a Focal Plane Array (FPA) that incorporates two technological building blocks developed over the past few years. The first one is a 10 μm InSb pixel based on the matured planar technology. The second building block is an innovative 10 μm ReadOut Integrated Circuit (ROIC) pixel. The InSb and the ROIC arrays are connected using Flip-Chip technology by means of indium bumps. The digital ROIC consists a matrix of 1920x1536 pixels and has an analog to digital (A/D) converter per-channel (total of 1920x2 A/Ds). It allows for full frame readout at a high frame rate of up to 120 Hz. Such an on-chip A/D conversion eliminates the need for several A/D converters with fairly high power consumption at the system level. The ROIC power consumption at maximum bandwidth is less than 400 mW. It features a wide range of pixel-level functionality such as several conversion gain options and a 2x2 pixel binning. The ROIC design makes use of the advanced and matured CMOS technology, 0.18 μm, which allows for high functionality and relatively low power consumption. The FPA is mounted on a Cold-Finger by a specially designed ceramic substrate. The whole assembly is housed in a stiffened Dewar that withstands harsh environmental conditions while minimizing the environment heat load contribution to the heat load of the detector. The design enables a 3-megapixel detector with overall low size, weight, and power (SWaP) with respect to comparable large format detectors. In this work we present in detail the characteristic performance of the new Blackbird detector.

  11. Charge-Sensitive Front-End Electronics with Operational Amplifiers for CdZnTe Detectors

    CERN Document Server

    Födisch, P; Lange, B; Kirschke, T; Enghardt, W; Kaever, P

    2016-01-01

    Cadmium zinc telluride (CdZnTe, "CZT") radiation detectors are announced to be a game-changing detector technology. However, state-of-the-art detector systems require high-performance readout electronics as well. Even though an application-specific integrated circuit (ASIC) is an adequate solution for the readout, our demands on a high dynamic range for energy measurement and a high throughput are not served by any commercially available circuit. Consequently, we had to develop the analog front-end electronics with operational amplifiers for an 8x8 pixelated CZT detector. For this purpose, we model an electrical equivalent circuit of the CZT detector with the associated charge-sensitive amplifier (CSA). Therefore, we present the mathematical equations for a detailed network analysis. Additionally, we enhance the design with numerical values for various features such as ballistic deficit, charge-to-voltage gain, rise time, noise level and verify the performance with synthetic detector signals. With this benchm...

  12. The high dynamic range pixel array detector (HDR-PAD): Concept and design

    Energy Technology Data Exchange (ETDEWEB)

    Shanks, Katherine S.; Philipp, Hugh T.; Weiss, Joel T.; Becker, Julian; Tate, Mark W. [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Gruner, Sol M., E-mail: smg26@cornell.edu [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853 (United States)

    2016-07-27

    Experiments at storage ring light sources as well as at next-generation light sources increasingly require detectors capable of high dynamic range operation, combining low-noise detection of single photons with large pixel well depth. XFEL sources in particular provide pulse intensities sufficiently high that a purely photon-counting approach is impractical. The High Dynamic Range Pixel Array Detector (HDR-PAD) project aims to provide a dynamic range extending from single-photon sensitivity to 10{sup 6} photons/pixel in a single XFEL pulse while maintaining the ability to tolerate a sustained flux of 10{sup 11} ph/s/pixel at a storage ring source. Achieving these goals involves the development of fast pixel front-end electronics as well as, in the XFEL case, leveraging the delayed charge collection due to plasma effects in the sensor. A first prototype of essential electronic components of the HDR-PAD readout ASIC, exploring different options for the pixel front-end, has been fabricated. Here, the HDR-PAD concept and preliminary design will be described.

  13. Enhanced R200 with Frisch-Grid CZT

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov, Aleksey [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-02-01

    Current technology using hand-held NaI scintillators with poor energy resolution can be greatly improved upon by using Virtual Frisch Grid-CZT detectors. The CZT semiconductor detectors will provide more reliable isotope identification and more precise measurement of photopeak areas in the presence of strong Compton background. The Virtual Frisch Grid design allows for correction of charge losses that occur at defects with much less expensive industrial grade crystals.

  14. TSV last for hybrid pixel detectors: Application to particle physics and imaging experiments

    CERN Document Server

    Henry, D; Berthelot, A; Cuchet, R; Chantre, C; Campbell, M

    Hybrid pixel detectors are now widely used in particle physics experiments and at synchrotron light sources. They have also stimulated growing interest in other fields and, in particular, in medical imaging. Through the continuous pursuit of miniaturization in CMOS it has been possible to increase the functionality per pixel while maintaining or even shrinking pixel dimensions. The main constraint on the more extensive use of the technology in all fields is the cost of module building and the difficulty of covering large areas seamlessly [1]. On another hand, in the field of electronic component integration, a new approach has been developed in the last years, called 3D Integration. This concept, based on using the vertical axis for component integration, allows improving the global performance of complex systems. Thanks to this technology, the cost and the form factor of components could be decreased and the performance of the global system could be enhanced. In the field of radiation imaging detectors the a...

  15. Simulation of active-edge pixelated CdTe radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, D.D., E-mail: diana.duarte@stfc.ac.uk [STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX (United Kingdom); Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Lipp, J.D.; Schneider, A.; Seller, P.; Veale, M.C.; Wilson, M.D. [STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX (United Kingdom); Baker, M.A.; Sellin, P.J. [Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

    2016-01-11

    The edge surfaces of single crystal CdTe play an important role in the electronic properties and performance of this material as an X-ray and γ-ray radiation detector. Edge effects have previously been reported to reduce the spectroscopic performance of the edge pixels in pixelated CdTe radiation detectors without guard bands. A novel Technology Computer Aided Design (TCAD) model based on experimental data has been developed to investigate these effects. The results presented in this paper show how localized low resistivity surfaces modify the internal electric field of CdTe creating potential wells. These result in a reduction of charge collection efficiency of the edge pixels, which compares well with experimental data.

  16. Development and characterization of a DEPFET pixel prototype system for the ILC vertex detector

    Energy Technology Data Exchange (ETDEWEB)

    Kohrs, Robert

    2008-09-15

    For the future TeV-scale linear collider ILC (International Linear Collider) a vertex detector of unprecedented performance is needed to fully exploit its physics potential. By incorporating a field effect transistor into a fully depleted sensor substrate the DEPFET (Depleted Field Effect Transistor) sensor combines radiation detection and in-pixel amplification. For the operation at a linear collider the excellent noise performance of DEPFET pixels allows building very thin detectors with a high spatial resolution and a low power consumption. With this thesis a prototype system consisting of a 64 x 128 pixels sensor, dedicated steering and readout ASICs and a data acquisition board has been developed and successfully operated in the laboratory and under realistic conditions in beam test environments at DESY and CERN. A DEPFET matrix has been successfully read out using the on-chip zero-suppression of the readout chip CURO 2. The results of the system characterization and beam test results are presented. (orig.)

  17. Test Beam Performance Measurements for the Phase I Upgrade of the CMS Pixel Detector

    CERN Document Server

    Dragicevic, M.; Hrubec, J.; Steininger, H.; Gädda, A.; Härkönen, J.; Lampén, T.; Luukka, P.; Peltola, T.; Tuominen, E.; Tuovinen, E.; Winkler, A.; Eerola, P.; Tuuva, T.; Baulieu, G.; Boudoul, G.; Caponetto, L.; Combaret, C.; Contardo, D.; Dupasquier, T.; Gallbit, G.; Lumb, N.; Mirabito, L.; Perries, S.; Donckt, M.Vander; Viret, S.; Bonnin, C.; Charles, L.; Gross, L.; Hosselet, J.; Tromson, D.; Feld, L.; Karpinski, W.; Klein, K.; Lipinski, M.; Pierschel, G.; Preuten, M.; Rauch, M.; Wlochal, M.; Aldaya, M.; Asawatangtrakuldee, C.; Beernaert, K.; Bertsche, D.; Contreras-Campana, C.; Eckerlin, G.; Eckstein, D.; Eichhorn, T.; Gallo, E.; Garcia, J.Garay; Hansen, K.; Haranko, M.; Harb, A.; Hauk, J.; Keaveney, J.; Kalogeropoulos, A.; Kleinwort, C.; Lohmann, W.; Mankel, R.; Maser, H.; Mittag, G.; Muhl, C.; Mussgiller, A.; Pitzl, D.; Reichelt, O.; Savitskyi, M.; Schütze, P.; Sola, V.; Spannagel, S.; Walsh, R.; Zuber, A.; Biskop, H.; Buhmann, P.; Centis-Vignali, M.; Garutti, E.; Haller, J.; Hoffmann, M.; Klanner, R.; Lapsien, T.; Matysek, M.; Perieanu, A.; Scharf, Ch.; Schleper, P.; Schmidt, A.; Schwandt, J.; Sonneveld, J.; Steinbrück, G.; Vormwald, B.; Wellhausen, J.; Abbas, M.; Amstutz, C.; Barvich, T.; Barth, Ch.; Boegelspacher, F.; Boer, W.De; Butz, E.; Casele, M.; Colombo, F.; Dierlamm, A.; Freund, B.; Hartmann, F.; Heindl, S.; Husemann, U.; Kornmeyer, A.; Kudella, S.; Muller, Th.; Simonis, H.J.; Steck, P.; Weber, M.; Weiler, Th.; Kiss, T.; Siklér, F.; Tölyhi, T.; Veszprémi, V.; Cariola, P.; Creanza, D.; Palma, M.De; Robertis, G.De; Fiore, L.; Franco, M.; Loddo, F.; Sala, G.; Silvestris, L.; Maggi, G.; My, S.; Selvaggi, G.; Albergo, S.; Cappello, G.; Costa, S.; Mattia, A.Di; Giordano, F.; Potenza, R.; Saizu, M.A.; Tricomi, A.; Tuve, C.; Focardi, E.; Dinardo, M.E.; Fiorendi, S.; Gennai, S.; Malvezzi, S.; Manzoni, R.A.; Menasce, D.; Moroni, L.; Pedrini, D.; Azzi, P.; Bacchetta, N.; Bisello, D.; Dall'Osso, M.; Pozzobon, N.; Tosi, M.; Solestizi, L.Alunni; Biasini, M.; Bilei, G.M.; Cecchi, C.; Checcucci, B.; Ciangottini, D.; Fanò, L.; Gentsos, C.; Ionica, M.; Leonardi, R.; Manoni, E.; Mantovani, G.; Marconi, S.; Mariani, V.; Menichelli, M.; Modak, A.; Morozzi, A.; Moscatelli, F.; Passeri, D.; Placidi, P.; Postolache, V.; Rossi, A.; Saha, A.; Santocchia, A.; Storchi, L.; Spiga, D.; Androsov, K.; Azzurri, P.; Bagliesi, G.; Basti, A.; Boccali, T.; Borrello, L.; Bosi, F.; Castaldi, R.; Ceccanti, M.; Ciocci, M.A.; Dell'Orso, R.; Donato, S.; Fedi, G.; Giassi, A.; Grippo, M.T.; Ligabue, F.; Magazzu, G.; Mammini, P.; Mariani, F.; Mazzoni, E.; Messineo, A.; Moggi, A.; Morsani, F.; Palla, F.; Palmonari, F.; Profeti, A.; Raffaelli, F.; Ragonesi, A.; Rizzi, A.; Soldani, A.; Spagnolo, P.; Tenchini, R.; Tonelli, G.; Venturi, A.; Verdini, P.G.; Abbaneo, D.; Ahmed, I.; Albert, E.; Auzinger, G.; Berruti, G.; Bonnaud, J.; Daguin, J.; D'Auria, A.; Detraz, S.; Dondelewski, O.; Engegaard, B.; Faccio, F.; Frank, N.; Gill, K.; Honma, A.; Kornmayer, A.; Labaza, A.; Manolescu, F.; McGill, I.; Mersi, S.; Michelis, S.; Onnela, A.; Ostrega, M.; Pavis, S.; Peisert, A.; Pernot, J.F.; Petagna, P.; Postema, H.; Rapacz, K.; Sigaud, C.; Tropea, P.; Troska, J.; Tsirou, A.; Vasey, F.; Verlaat, B.; Vichoudis, P.; Zwalinski, L.; Bachmair, F.; Becker, R.; di Calafiori, D.; Casal, B.; Berger, P.; Djambazov, L.; Donega, M.; Grab, C.; Hits, D.; Hoss, J.; Kasieczka, G.; Lustermann, W.; Mangano, B.; Marionneau, M.; Arbol, P.Martinez Ruiz del; Masciovecchio, M.; Meinhard, M.; Perozzi, L.; Roeser, U.; Starodumov, A.; Tavolaro, V.; Wallny, R.; Zhu, D.; Amsler, C.; Bösiger, K.; Caminada, L.; Canelli, F.; Chiochia, V.; de Cosa, A.; Galloni, C.; Hreus, T.; Kilminster, B.; Lange, C.; Maier, R.; Ngadiuba, J.; Pinna, D.; Robmann, P.; Taroni, S.; Yang, Y.; Bertl, W.; Deiters, K.; Erdmann, W.; Horisberger, R.; Kaestli, H.C.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Streuli, S.; Chen, P.H.; Dietz, C.; Fiori, F.; Grundler, U.; Hou, W.S.; Lu, R.S.; Moya, M.; Tsai, J.F.; Tzeng, Y.M.; Cussans, D.; Goldstein, J.; Grimes, M.; Newbold, D.; Hobson, P.; Reid, I.D.; Auzinger, G.; Bainbridge, R.; Dauncey, P.; Hall, G.; James, T.; Magnan, A.M.; Pesaresi, M.; Raymond, D.M.; Uchida, K.; Durkin, T.; Harder, K.; Shepherd-Themistocleous, C.; Chertok, M.; Conway, J.; Conway, R.; Flores, C.; Lander, R.; Pellett, D.; Ricci-Tam, F.; Squires, M.; Thomson, J.; Yohay, R.; Burt, K.; Ellison, J.; Hanson, G.; Olmedo, M.; Si, W.; Yates, B.R.; Dominguez, A.; Bartek, R.; Bentele, B.; Cumalat, J.P.; Ford, W.T.; Jensen, F.; Johnson, A.; Krohn, M.; Leontsinis, S.; Mulholland, T.; Stenson, K.; Wagner, S.R.; Apresyan, A.; Bolla, G.; Burkett, K.; Butler, J.N.; Canepa, A.; Cheung, H.W.K.; Christian, D.; Cooper, W.E.; Deptuch, G.; Derylo, G.; Gingu, C.; Grünendahl, S.; Hasegawa, S.; Hoff, J.; Howell, J.; Hrycyk, M.; Jindariani, S.; Johnson, M.; Kahlid, F.; Kwan, S.; Lei, C.M.; Lipton, R.; Sá, R.Lopes De; Liu, T.; Los, S.; Matulik, M.; Merkel, P.; Nahn, S.; Prosser, A.; Rivera, R.; Schneider, B.; Sellberg, G.; Shenai, A.; Siehl, K.; Spiegel, L.; Tran, N.; Uplegger, L.; Voirin, E.; Berry, D.R.; Chen, X.; Ennesser, L.; Evdokimov, A.; Gerber, C.E.; Makauda, S.; Mills, C.; Gonzalez, I.D.Sandoval; Alimena, J.; Antonelli, L.J.; Francis, B.; Hart, A.; Hill, C.S.; Parashar, N.; Stupak, J.; Bortoletto, D.; Bubna, M.; Hinton, N.; Jones, M.; Miller, D.H.; Shi, X.; Baringer, P.; Bean, A.; Khalil, S.; Kropivnitskaya, A.; Majumder, D.; Schmitz, E.; Wilson, G.; Ivanov, A.; Mendis, R.; Mitchell, T.; Skhirtladze, N.; Taylor, R.; Anderson, I.; Fehling, D.; Gritsan, A.; Maksimovic, P.; Martin, C.; Nash, K.; Osherson, M.; Swartz, M.; Xiao, M.; Acosta, J.G.; Cremaldi, L.M.; Oliveros, S.; Perera, L.; Summers, D.; Bloom, K.; Claes, D.R.; Fangmeier, C.; Suarez, R.Gonzalez; Monroy, J.; Siado, J.; Bartz, E.; Gershtein, Y.; Halkiadakis, E.; Kyriacou, S.; Lath, A.; Nash, K.; Osherson, M.; Schnetzer, S.; Stone, R.; Walker, M.; Malik, S.; Norberg, S.; Vargas, J.E.Ramirez; Alyari, M.; Dolen, J.; Godshalk, A.; Harrington, C.; Iashvili, I.; Kharchilava, A.; Nguyen, D.; Parker, A.; Rappoccio, S.; Roozbahani, B.; Alexander, J.; Chaves, J.; Chu, J.; Dittmer, S.; McDermott, K.; Mirman, N.; Rinkevicius, A.; Ryd, A.; Salvati, E.; Skinnari, L.; Soffi, L.; Tao, Z.; Thom, J.; Tucker, J.; Zientek, M.; Akgün, B.; Ecklund, K.M.; Kilpatrick, M.; Nussbaum, T.; Zabel, J.; D'Angelo, P.; Johns, W.; Rose, K.

    2017-05-30

    A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These upgrades allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. In this paper, comprehensive test beam studies are presented which have been conducted to verify the design and to quantify the performance of the new detector assemblies in terms of tracking efficiency and spatial resolution. Under optimal conditions, the tracking efficiency has been determined to be ($99.95 \\pm 0.05$) \\%, while the intrinsic spatial resolution has been measured to be ($4.80 \\pm 0.25$) $\\mu$m and ($7.99 \\pm 0.21$...

  18. The Pixel Detector of the ATLAS Experiment for the Run-2 at the Large Hadron Collider

    CERN Document Server

    Guescini, F; The ATLAS collaboration

    2014-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radial distance of 3.3 cm from the beam axis. The realization of the IBL required the development of several new technologies and solutions in order to overcome the challenges introduced by the extreme environment and working conditions, such as the high radiation levels, the high pixel occupancy and the need of an exceptionally low material budget. Two silicon sensor technologies have been adopted for the IBL modules: planar n-in-n and 3D. Both of these are connected via bump bonding to the new generation 130 nm IBM CMOS FE-I4 ...

  19. Low noise pixel detectors based on gated geiger mode avalanche photodiodes

    OpenAIRE

    Vilella Figueras, Eva; Comerma Montells, Albert; Alonso Casanovas, Oscar; Diéguez Barrientos, Àngel

    2011-01-01

    The gated operation is proposed as an effective method to reduce the noise in pixel detectors based on Geiger mode avalanche photodiodes. A prototype with the sensor and the front-end electronics monolithically integrated has been fabricated with a conventional HV-CMOS process. Experimental results demonstrate the increase of the dynamic range of the sensor by applying this technique.

  20. Design and TCAD simulation of double-sided pixelated low gain avalanche detectors

    Energy Technology Data Exchange (ETDEWEB)

    Dalla Betta, Gian-Franco, E-mail: gianfranco.dallabetta@unitn.it [Dipartimento di Ingegneria Industriale, Università di Trento, Via Sommarive 9, 38123 Trento (Italy); TIFPA INFN, Via Sommarive 14, 38123 Trento (Italy); Pancheri, Lucio [Dipartimento di Ingegneria Industriale, Università di Trento, Via Sommarive 9, 38123 Trento (Italy); TIFPA INFN, Via Sommarive 14, 38123 Trento (Italy); Boscardin, Maurizio [Fondazione Bruno Kessler, Via Sommarive 18, 38123 Trento (Italy); TIFPA INFN, Via Sommarive 14, 38123 Trento (Italy); Paternoster, Giovanni [Fondazione Bruno Kessler, Via Sommarive 18, 38123 Trento (Italy); Piemonte, Claudio [Fondazione Bruno Kessler, Via Sommarive 18, 38123 Trento (Italy); TIFPA INFN, Via Sommarive 14, 38123 Trento (Italy); Cartiglia, Nicolo; Cenna, Francesca [INFN Sezione di Torino, Via P. Giuria 2, 10125 Torino (Italy); Bruzzi, Mara [Dipartimento di FIsica e Astronomia, Università di Firenze, and INFN Sezione di Firenze, Via Giovanni Sansone 1, 50019 Sesto Fiorentino (Italy)

    2015-10-01

    We introduce a double-sided variant of low gain avalanche detector, suitable for pixel arrays without dead-area in between the different read-out elements. TCAD simulations were used to validate the device concept and predict its performance. Different design options and selected simulation results are presented, along with the proposed fabrication process.

  1. Cluster Properties and Lorentz Angle Measurement in the 4-Layer Pixel Detector Using Cosmic Rays

    CERN Document Server

    The ATLAS collaboration

    2015-01-01

    The 4-layer Pixel Detector with the recently installed innermost layer called IBL saw its first data during the 2014 fall cosmic run. This note shows cluster properties and Lorentz angle fits for IBL sensors as well as old barrel layer sensors.

  2. A near-infrared 64-pixel superconducting nanowire single photon detector array with integrated multiplexed readout

    Energy Technology Data Exchange (ETDEWEB)

    Allman, M. S., E-mail: shane.allman@boulder.nist.gov; Verma, V. B.; Stevens, M.; Gerrits, T.; Horansky, R. D.; Lita, A. E.; Mirin, R.; Nam, S. W. [National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305-3328 (United States); Marsili, F.; Beyer, A.; Shaw, M. D. [Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, California 91109 (United States); Kumor, D. [Purdue University, 610 Purdue Mall, West Lafayette, Indiana 47907 (United States)

    2015-05-11

    We demonstrate a 64-pixel free-space-coupled array of superconducting nanowire single photon detectors optimized for high detection efficiency in the near-infrared range. An integrated, readily scalable, multiplexed readout scheme is employed to reduce the number of readout lines to 16. The cryogenic, optical, and electronic packaging to read out the array as well as characterization measurements are discussed.

  3. A Near-Infrared 64-pixel Superconducting Nanowire Single Photon Detector Array with Integrated Multiplexed Readout

    CERN Document Server

    Allman, M S; Stevens, M; Gerrits, T; Horansky, R D; Lita, A E; Marsili, F; Beyer, A; Shaw, M D; Kumor, D; Mirin, R; Nam, S W

    2015-01-01

    We demonstrate a 64-pixel free-space-coupled array of superconducting nanowire single photon detectors optimized for high detection efficiency in the near-infrared range. An integrated, readily scalable, multiplexed readout scheme is employed to reduce the number of readout lines to 16. The cryogenic, optical, and electronic packaging to read out the array, as well as characterization measurements are discussed.

  4. Module production for the Phase 1 upgrade of the CMS forward pixel detector

    Science.gov (United States)

    Siado Castaneda, Joaquin

    2017-01-01

    For Run 2 the Large Hadron Collider will run at a much higher instantaneous luminosity, which requires an upgrade of the CMS pixel detector. The detector consists of rectangular silicon sensors, segmented into 100 μm by 150 μm pixels, bonded to readout chips, with one sensor and a 8x2 array of readout chips forming a module. Due to its high granularity and good spatial resolution, about 10 μm for a single hit, the pixel detector is used for track reconstruction, pileup mitigation, and b-quark tagging in many physics analyses. Being the innermost sub-detector of CMS it receives the most radiation damage, and therefore needs to be replaced most often. For the phase 1 upgrade an additional disk in the forward region and increased buffer space in the readout chip will improve the pixel performance by increasing efficiency and reducing fake rates. The University of Nebraska-Lincoln is one of the two sites where modules are being assembled. This talk features the steps of the assembly process as well as challenges encountered and overcome during production of over 500 modules. The CMS Collaboration.

  5. A method for precise charge reconstruction with pixel detectors using binary hit information

    CERN Document Server

    Pohl, David-Leon; Hemperek, Tomasz; Hügging, Fabian; Wermes, Norbert

    2014-01-01

    A method is presented to precisely reconstruct charge spectra with pixel detectors using binary hit information of individual pixels. The method is independent of the charge information provided by the readout circuitry and has a resolution mainly limited by the electronic noise. It relies on the ability to change the detection threshold in small steps while counting hits from a particle source. The errors are addressed and the performance of the method is shown based on measurements with the ATLAS pixel chip FE-I4 bump bonded to a 230 {\\mu}m 3D-silicon sensor. Charge spectra from radioactive sources and from electron beams are presented serving as examples. It is demonstrated that a charge resolution ({\\sigma}<200 e) close to the electronic noise of the ATLAS FE-I4 pixel chip can be achieved.

  6. 18k Channels single photon counting readout circuit for hybrid pixel detector

    Science.gov (United States)

    Maj, P.; Grybos, P.; Szczygiel, R.; Zoladz, M.; Sakumura, T.; Tsuji, Y.

    2013-01-01

    We have performed measurements of an integrated circuit named PXD18k designed for hybrid pixel semiconductor detectors used in X-ray imaging applications. The PXD18k integrated circuit, fabricated in CMOS 180 nm technology, has dimensions of 9.64 mm×20 mm and contains approximately 26 million transistors. The core of the IC is a matrix of 96×192 pixels with 100 μm×100 μm pixel size. Each pixel works in a single photon counting mode. A single pixel contains two charge sensitive amplifiers with Krummenacher feedback scheme, two shapers, two discriminators (with independent thresholds A and B) and two 16-bit ripple counters. The data are read out via eight low voltage differential signaling (LVDS) outputs with 100 Mbps rate. The power consumption is dominated by analog blocks and it is about 23 μW/pixel. The effective peaking time at the discriminator input is 30 ns and is mainly determined by the time constants of the charge sensitive amplifier (CSA). The gain is equal to 42.5 μV/e- and the equivalent noise charge is 168 e- rms (with bump-bonded silicon pixel detector). Thanks to the use of trim DACs in each pixel, the effective threshold spread at the discriminator input is only 1.79 mV. The dead time of the front end electronics for a standard setting is 172 ns (paralyzable model). In the standard readout mode (when the data collection time is separated from the time necessary to readout data from the chip) the PXD18k IC works with two energy thresholds per pixel. The PXD18k can also be operated in the continuous readout mode (with a zero dead time) where one can select the number of bits readout from each pixel to optimize the PXD18k frame rate. For example, for reading out 16 bits/pixel the frame rate is 2.7 kHz and for 4 bits/pixel it rises to 7.1 kHz.

  7. 18k Channels single photon counting readout circuit for hybrid pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Maj, P., E-mail: piotr.maj@agh.edu.pl [AGH University of Science and Technology, Department of Measurements and Electronics, Al. Mickiewicza 30, 30-059 Krakow (Poland); Grybos, P.; Szczygiel, R.; Zoladz, M. [AGH University of Science and Technology, Department of Measurements and Electronics, Al. Mickiewicza 30, 30-059 Krakow (Poland); Sakumura, T.; Tsuji, Y. [X-ray Analysis Division, Rigaku Corporation, Matsubara, Akishima, Tokyo 196-8666 (Japan)

    2013-01-01

    We have performed measurements of an integrated circuit named PXD18k designed for hybrid pixel semiconductor detectors used in X-ray imaging applications. The PXD18k integrated circuit, fabricated in CMOS 180 nm technology, has dimensions of 9.64 mm Multiplication-Sign 20 mm and contains approximately 26 million transistors. The core of the IC is a matrix of 96 Multiplication-Sign 192 pixels with 100 {mu}m Multiplication-Sign 100 {mu}m pixel size. Each pixel works in a single photon counting mode. A single pixel contains two charge sensitive amplifiers with Krummenacher feedback scheme, two shapers, two discriminators (with independent thresholds A and B) and two 16-bit ripple counters. The data are read out via eight low voltage differential signaling (LVDS) outputs with 100 Mbps rate. The power consumption is dominated by analog blocks and it is about 23 {mu}W/pixel. The effective peaking time at the discriminator input is 30 ns and is mainly determined by the time constants of the charge sensitive amplifier (CSA). The gain is equal to 42.5 {mu}V/e{sup -} and the equivalent noise charge is 168 e{sup -} rms (with bump-bonded silicon pixel detector). Thanks to the use of trim DACs in each pixel, the effective threshold spread at the discriminator input is only 1.79 mV. The dead time of the front end electronics for a standard setting is 172 ns (paralyzable model). In the standard readout mode (when the data collection time is separated from the time necessary to readout data from the chip) the PXD18k IC works with two energy thresholds per pixel. The PXD18k can also be operated in the continuous readout mode (with a zero dead time) where one can select the number of bits readout from each pixel to optimize the PXD18k frame rate. For example, for reading out 16 bits/pixel the frame rate is 2.7 kHz and for 4 bits/pixel it rises to 7.1 kHz.

  8. Developing fine-pixel CdTe detectors for the next generation of high-resolution hard x-ray telescopes

    Science.gov (United States)

    Christe, Steven

    Over the past decade, the NASA Marshall Space Flight Center (MSFC) has been improving the angular resolution of hard X-ray (HXR; 20 "70 keV) optics to the point that we now routinely manufacture optics modules with an angular resolution of 20 arcsec Half Power Diameter (HDP), almost three times the performance of NuSTAR optics (Ramsey et al. 2013; Gubarev et al. 2013a; Atkins et al. 2013). New techniques are currently being developed to provide even higher angular resolution. High angular resolution HXR optics require detectors with a large number of fine pixels in order to adequately sample the telescope point spread function (PSF) over the entire field of view. Excessively over-sampling the PSF will increase readout noise and require more processing with no appreciable increase in image quality. An appropriate level of over-sampling is to have 3 pixels within the HPD. For the HERO mirrors, where the HPD is 26 arcsec over a 6-m focal length converts to 750 μm, the optimum pixel size is around 250 μm. At a 10-m focal length these detectors can support a 16 arcsec HPD. Of course, the detectors must also have high efficiency in the HXR region, good energy resolution, low background, low power requirements, and low sensitivity to radiation damage (Ramsey 2001). The ability to handle high counting rates is also desirable for efficient calibration. A collaboration between Goddard Space Flight Center (GSFC), MSFC, and Rutherford Appleton Laboratory (RAL) in the UK is developing precisely such detectors under an ongoing, funded APRA program (FY2015 to FY2017). The detectors use the RALdeveloped Application Specific Integrated Circuit (ASIC) dubbed HEXITEC, for High Energy X-Ray Imaging Technology. These HEXITEC ASICs can be bonded to 1- or 2- mm-thick Cadmium Telluride (CdTe) or Cadmium-Zinc-Telluride (CZT) to create a fine (250 μm pitch) HXR detector (Jones et al. 2009; Seller et al. 2011). The objectives of this funded effort are to develop and test a HEXITEC

  9. Operational Experience of the ATLAS SemiConductor Tracker and Pixel Detector

    CERN Document Server

    Robinson, Dave; The ATLAS collaboration

    2016-01-01

    The tracking performance of the ATLAS detector relies critically on the silicon and gaseous tracking subsystems that form the ATLAS Inner Detector. Those subsystems have undergone significant hardware and software upgrades to meet the challenges imposed by the higher collision energy, pileup and luminosity that are being delivered by the LHC during Run2. The key status and performance metrics of the Pixel Detector and the Semi Conductor Tracker are summarised, and the operational experience and requirements to ensure optimum data quality and data taking efficiency are described.

  10. Towards hybrid pixel detectors for energy-dispersive or soft X-ray photon science.

    Science.gov (United States)

    Jungmann-Smith, J H; Bergamaschi, A; Brückner, M; Cartier, S; Dinapoli, R; Greiffenberg, D; Huthwelker, T; Maliakal, D; Mayilyan, D; Medjoubi, K; Mezza, D; Mozzanica, A; Ramilli, M; Ruder, Ch; Schädler, L; Schmitt, B; Shi, X; Tinti, G

    2016-03-01

    JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications at free-electron lasers and synchrotron light sources. The JUNGFRAU 0.4 prototype presented here is specifically geared towards low-noise performance and hence soft X-ray detection. The design, geometry and readout architecture of JUNGFRAU 0.4 correspond to those of other JUNGFRAU pixel detectors, which are charge-integrating detectors with 75 µm × 75 µm pixels. Main characteristics of JUNGFRAU 0.4 are its fixed gain and r.m.s. noise of as low as 27 e(-) electronic noise charge (X-ray irradiation from an X-ray tube and a synchrotron light source are successfully demonstrated with an r.m.s. energy resolution of 20% (no mask) and 14% (with the mask) at 1.2 keV and of 5% at 13.3 keV. The performance evaluation of the JUNGFRAU 0.4 prototype suggests that this detection system could be the starting point for a future detector development effort for either applications in the soft X-ray energy regime or for an energy-dispersive detection system.

  11. X-ray Imaging Using a Hybrid Photon Counting GaAs Pixel Detector

    CERN Document Server

    Schwarz, C; Göppert, R; Heijne, Erik H M; Ludwig, J; Meddeler, G; Mikulec, B; Pernigotti, E; Rogalla, M; Runge, K; Smith, K M; Snoeys, W; Söldner-Rembold, S; Watt, J

    1999-01-01

    The performance of hybrid GaAs pixel detectors as X-ray imaging sensors were investigated at room temperature. These hybrids consist of 300 mu-m thick GaAs pixel detectors, flip-chip bonded to a CMOS Single Photon Counting Chip (PCC). This chip consists of a matrix of 64 x 64 identical square pixels (170 mu-m x 170 mu-m) and covers a total area of 1.2 cm**2. The electronics in each cell comprises a preamplifier, a discriminator with a 3-bit threshold adjust and a 15-bit counter. The detector is realized by an array of Schottky diodes processed on semi-insulating LEC-GaAs bulk material. An IV-charcteristic and a detector bias voltage scan showed that the detector can be operated with voltages around 200 V. Images of various objects were taken by using a standard X-ray tube for dental diagnostics. The signal to noise ratio (SNR) was also determined. The applications of these imaging systems range from medical applications like digital mammography or dental X-ray diagnostics to non destructive material testing (...

  12. Real-time control of the beam attenuation with XPAD hybrid pixel detector

    Science.gov (United States)

    Dawiec, A.; Garreau, Y.; Bisou, J.; Hustache, S.; Kanoute, B.; Picca, F.; Renaud, G.; Coati, A.

    2016-12-01

    In order to fully benefit from a beam produced by modern synchrotron light sources, characterised by a wide and continuous energy spectrum, high brightness and a very high intensity, advancement in detector technology has been made over the last decades. However, one of the main limitations of the state-of-the-art counting hybrid pixel detectors is the maximum count-rate that is very often few orders of magnitudes lower than of the incident, reflected or diffracted beam flux. Therefore, direct beam attenuation is mandatory in order to perform the measurements according to the detector's characteristics. In this work we present a major upgrade of a fast attenuation system developed at Synchrotron SOLEIL, which allows for a dynamical change of the beam attenuation as a function of the photon flux received by XPAD S140 photon counting detector. The system performs a cyclic real-time estimation of the flux received by every pixel during acquisition of an image and searches for clusters of at least two pixels that exceed user defined levels of counts/s. The beam attenuation is immediately and automatically changed in order to guarantee that the detector will always operate in its linear range even during a long continuous scan, by acting on the direct attenuators.

  13. Boundary scan test of Belle II pixel detector electronics

    Energy Technology Data Exchange (ETDEWEB)

    Leitl, Philipp [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany)

    2015-07-01

    For the upgrade of the Vertex Detector at the Belle II experiment, DEPFET sensors will be used. These sensors need Application-Specific Integrated Circuits (ASICs) for control, readout and data processing. Because of high demands for a low material budget in the sensitive area, there is only little space left for these ASICs. Using state-of-the-art technologies like Ball Grid Array (BGA) chips, which are flip-chip mounted, the requirement of 14 ASICs on each of the 40 half ladders can be fulfilled. However, this highly integrated on-sensor ASIC solution results in a lack of physical access to the electrical connections, which is a problem for traditional testing methods. To overcome these limitations, the JTAG standard IEEE 1149.1 is used to check if the circuit is in working condition. This method provides electrical access to the boundary scan cells implemented in the ASICs. Therefore it is possible to perform connectivity tests and verify if the production of the circuit was successful.

  14. TCAD simulations of High-Voltage-CMOS Pixel structures for the CLIC vertex detector

    CERN Document Server

    Buckland, Matthew Daniel

    2016-01-01

    The requirements for precision physics and the experimental conditions at CLIC result in stringent constraints for the vertex detector. Capacitively coupled active pixel sensors with 25 μm pitch implemented in a commercial 180 nm High-Voltage CMOS (HV-CMOS) process are currently under study as a candidate technology for the CLIC vertex detector. Laboratory calibration measurements and beam tests with prototypes are complemented by detailed TCAD and electronic circuit simulations, aiming for a comprehensive understanding of the signal formation in the HV-CMOS sensors and subsequent readout stages. In this note 2D and 3D TCAD simulation results of the prototype sensor, the Capacitively Coupled Pixel Detector version three (CCPDv3), will be presented. These include the electric field distribution, leakage current, well capacitance, transient response to minimum ionising particles and charge-collection.

  15. Development of 3D-DDTC pixel detectors for the ATLAS upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Dalla Betta, Gian-Franco, E-mail: dallabe@disi.unitn.it [INFN, Sezione di Padova (Gruppo Collegato di Trento), and DISI, Universita di Trento, Via Sommarive 14, 38123 Povo di Trento (Italy); Boscardin, Maurizio [Fondazione Bruno Kessler (FBK-irst), Via Sommarive 18, 38123 Povo di Trento (Italy); Darbo, Giovanni; Gemme, Claudia [INFN, Sezione di Genova, Via Dodecaneso 33, 16146 Genova (Italy); La Rosa, Alessandro; Pernegger, Heinz [CERN-PH, CH-1211 Geneve 23 (Switzerland); Piemonte, Claudio [Fondazione Bruno Kessler (FBK-irst), Via Sommarive 18, 38123 Povo di Trento (Italy); Povoli, Marco [INFN, Sezione di Padova (Gruppo Collegato di Trento), and DISI, Universita di Trento, Via Sommarive 14, 38123 Povo di Trento (Italy); Ronchin, Sabina [Fondazione Bruno Kessler (FBK-irst), Via Sommarive 18, 38123 Povo di Trento (Italy); Zoboli, Andrea [INFN, Sezione di Padova (Gruppo Collegato di Trento), and DISI, Universita di Trento, Via Sommarive 14, 38123 Povo di Trento (Italy); Zorzi, Nicola [Fondazione Bruno Kessler (FBK-irst), Via Sommarive 18, 38123 Povo di Trento (Italy)

    2011-04-21

    We report on the development of n-on-p, 3D Double-Side Double Type Column (3D-DDTC) pixel detectors fabricated at FBK-irst (Trento, Italy) and oriented to the ATLAS upgrade. The considered fabrication technology is simpler than that required for full 3D detectors with active edge, but the detector efficiency and radiation hardness critically depend on the columnar electrode overlap and should be carefully evaluated. The first assemblies of these sensors (featuring 2, 3, or 4 columns per pixel) with the ATLAS FEI3 read-out chip have been tested in laboratory. Selected results from the electrical and functional characterization with radioactive sources are discussed here.

  16. Development of 3D-DDTC pixel detectors for the ATLAS upgrade

    CERN Document Server

    Betta, G -F Dalla; Darbo, G; Gemme, C; La Rosa, A; Pernegger, H; Piemonte, C; Povoli, M; Ronchin, S; Zoboli, A; Zorzi, N

    2011-01-01

    We report on the development of n-on-p, 3D Double-Side Double Type Column (3D-DDTC) pixel detectors fabricated at FBK-irst (Trento, Italy) and oriented to the ATLAS upgrade. The considered fabrication technology is simpler than that required for full 3D detectors with active edge, but the detector efficiency and radiation hardness critically depend on the columnar electrode overlap and should be carefully evaluated. The first assemblies of these sensors (featuring 2, 3, or 4 columns per pixel) with the ATLAS FEI3 read-out chip have been tested in laboratory. Selected results from the electrical and functional characterization with radioactive sources are here discussed.

  17. DEPFET: A silicon pixel detector for future colliders. Fundamentals, characterization and performance

    CERN Document Server

    Marinas Pardo, Carlos Manuel; Vos, Marcel Andre

    2011-01-01

    The future electron-positron colliders, either breaking the energy frontier (like ILC or CLIC) or the luminosity frontier (SuperKEKB), impose unprecedented constraints over the new generation of detectors that will be operated in those facilities. In particular, the vertex detectors must be designed for an efficient flavour tagging and excellent vertex reconstruction. To cope with these requirements, highly pixelated sensors with a fast readout, very low material budget and low power consumption must be developed. Although the combination of these factors is a substantial challenge, the DEPFET Collaboration has developed a new generation of sensors that can be operated in such a harsh environment. The DEpleted P-channel Field Effect Transistor (DEPFET) is a pixel sensor that combines detection and internal amplification at the same time. With such configuration, thin detectors with good signal-to-noise ratio and low power consumption can be produced. In this thesis, the optimization and performance of two gen...

  18. Development of the Pixelated Photon Detector Using Silicon on Insulator Technology for TOF-PET

    CERN Document Server

    Koyama, Akihiro; Takahashi, Hiroyuki; Orita, Tadashi; Arai, Yasuo; Kurachi, Ikuo; Miyoshi, Toshinobu; Nio, Daisuke; Hamasaki, Ryutaro

    2015-01-01

    To measure light emission pattern in scintillator, higher sensitivity and faster response are required to photo detector. Such as single photon avalanche diode (SPAD), conventional pixelated photo detector is operated at Geiger avalanche multiplication. However higher gain of SPAD seems very attractive, photon detection efficiency per unit area is low. This weak point is mainly caused by Geiger avalanche mechanism. To overcome these difficulties, we designed Pixelated Linear Avalanche Integration Detector using Silicon on Insulator technology (SOI-Plaid). To avoid dark count noise and dead time comes from quench circuit, we are planning to use APD in linear multiplication mode. SOI technology enables laminating readout circuit and APD layer, and high-speed and low-noise signal reading regardless smaller gain of linear APD. This study shows design of linear APD by using SOI fabrication process. We designed test element group (TEG) of linear APD and inspected optimal structure of linear APD.

  19. Analysis of Full Charge Reconstruction Algorithms for X-Ray Pixelated Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Baumbaugh, A.; /Fermilab; Carini, G.; /SLAC; Deptuch, G.; /Fermilab; Grybos, P.; /AGH-UST, Cracow; Hoff, J.; /Fermilab; Siddons, P., Maj.; /Brookhaven; Szczygiel, R.; /AGH-UST, Cracow; Trimpl, M.; Yarema, R.; /Fermilab

    2012-05-21

    Existence of the natural diffusive spread of charge carriers on the course of their drift towards collecting electrodes in planar, segmented detectors results in a division of the original cloud of carriers between neighboring channels. This paper presents the analysis of algorithms, implementable with reasonable circuit resources, whose task is to prevent degradation of the detective quantum efficiency in highly granular, digital pixel detectors. The immediate motivation of the work is a photon science application requesting simultaneous timing spectroscopy and 2D position sensitivity. Leading edge discrimination, provided it can be freed from uncertainties associated with the charge sharing, is used for timing the events. Analyzed solutions can naturally be extended to the amplitude spectroscopy with pixel detectors.

  20. Analysis of full charge reconstruction algorithms for x-ray pixelated detectors

    Energy Technology Data Exchange (ETDEWEB)

    Baumbaugh, A.; /Fermilab; Carini, G.; /SLAC; Deptuch, G.; /Fermilab; Grybos, P.; /AGH-UST, Cracow; Hoff, J.; /Fermilab; Siddons, P., Maj.; /Brookhaven; Szczygiel, R.; /AGH-UST, Cracow; Trimpl, M.; Yarema, R.; /Fermilab

    2011-11-01

    Existence of the natural diffusive spread of charge carriers on the course of their drift towards collecting electrodes in planar, segmented detectors results in a division of the original cloud of carriers between neighboring channels. This paper presents the analysis of algorithms, implementable with reasonable circuit resources, whose task is to prevent degradation of the detective quantum efficiency in highly granular, digital pixel detectors. The immediate motivation of the work is a photon science application requesting simultaneous timing spectroscopy and 2D position sensitivity. Leading edge discrimination, provided it can be freed from uncertainties associated with the charge sharing, is used for timing the events. Analyzed solutions can naturally be extended to the amplitude spectroscopy with pixel detectors.

  1. ProtoEXIST: advanced prototype CZT coded aperture telescopes for EXIST

    Science.gov (United States)

    Allen, Branden; Hong, Jaesub; Grindlay, Josh; Barthelmy, Scott D.; Baker, Robert G.; Gehrels, Neil A.; Garson, Trey; Krawczynski, Henric S.; Cook, Walter R.; Harrison, Fiona A.; Apple, Jeffrey A.; Ramsey, Brian D.

    2010-07-01

    ProtoEXIST1 is a pathfinder for the EXIST-HET, a coded aperture hard X-ray telescope with a 4.5 m2 CZT detector plane a 90x70 degree field of view to be flown as the primary instrument on the EXIST mission and is intended to monitor the full sky every 3 h in an effort to locate GRBs and other high energy transients. ProtoEXIST1 consists of a 256 cm2 tiled CZT detector plane containing 4096 pixels composed of an 8x8 array of individual 1.95 cm x 1.95 cm x 0.5 cm CZT detector modules each with a 8 x 8 pixilated anode configured as a coded aperture telescope with a fully coded 10° x 10° field of view employing passive side shielding and an active CsI anti-coincidence rear shield, recently completed its maiden flight out of Ft. Sumner, NM on the 9th of October 2009. During the duration of its 6 hour flight on-board calibration of the detector plane was carried out utilizing a single tagged 198.8 nCi Am-241 source along with the simultaneous measurement of the background spectrum and an observation of Cygnus X-1. Here we recount the events of the flight and report on the detector performance in a near space environment. We also briefly discuss ProtoEXIST2: the next stage of detector development which employs the NuSTAR ASIC enabling finer (32×32) anode pixilation. When completed ProtoEXIST2 will consist of a 256 cm2 tiled array and be flown simultaneously with the ProtoEXIST1 telescope.

  2. Design of a Low-Noise Readout Circuit for CZT Detector%CZT探测器低噪声读出电路设计

    Institute of Scientific and Technical Information of China (English)

    曾蕙明; 魏廷存; 高武

    2013-01-01

    采用TSMC 0.35 μm CMOS工艺,设计了CZT探测器低噪声读出电路链和一款多通道能量读出ASIC,该电路将应用于8×8 CZT像素探测器的能量读出.给出了系统框图及低噪声能量读出电路链,分析了低噪声技术策略.实验结果表明,能量分辨范围为20 keV~4 MeV,等效噪声电荷(ENC)小于150个电子,电荷转电压增益为9.2 V/pC,非线性度小于3%,多通道串扰小于10个电子,满足设计需求.%A low-noise front-end readout circuit chain and a multi-channel energy readout ASIC for CZT detector in PET imaging system were designed based on TSMC's 0.35 μm mixed-signal CMOS process.Architecture of the PET imaging system and the low-noise energy readout circuit chain were presented,and low-noise technology strategy was analyzed.Simulation results showed that the energy resolution was from 20 keV to 4 MeV,the equivalent noise charge (ENC) was less than 150 electrons (rms),the charge-to-voltage gain was 9.2 V/pC,the non-linearity was below 3%,and crosstalk of multi channels was less than 10 electrons,satisfying requirements of the design.

  3. Finite-element simulations of coupling capacitances in capacitively coupled pixel detectors

    CERN Document Server

    AUTHOR|(SzGeCERN)755510

    2017-01-01

    Capacitively coupled hybrid silicon pixel-detector assemblies are under study for the vertex detector at the proposed future CLIC linear electron-positron collider. The assemblies consist of active CCPDv3 sensors, with 25 μm pixel pitch implemented in a 180 nm High- Voltage CMOS process, which are glued to the CLICpix readout ASIC, with the same pixel pitch and processed in a commercial 65 nm CMOS technology. The signal created in the silicon bulk of the active sensors passes a two-stage amplifier, in each pixel, and gets transferred as a voltage pulse to metal pads facing the readout chip (ROC). The coupling of the signal to the metal pads on the ROC side proceeds through the capacitors formed between the two chips by a thin layer of epoxy glue. The coupling strength and the amount of unwanted cross coupling to neighbouring pixels depends critically on the uniformity of the glue layer, its thickness and on the alignment precision during the flip-chip assembly process. Finite-element calculations of the coup...

  4. Data concentrator with FPGA-based track reconstruction for the Belle II DEPFET pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Schnell, Michael; Dingfelder, Jochen; Marinas, Carlos [Physikalisches Institut, Universitaet Bonn (Germany)

    2013-07-01

    The innermost two layers of the Belle II vertex detector at the KEK facility in Tsukuba, Japan, will be covered by high-granularity DEPFET pixel sensors. The large number of pixels leads to a high data rate of around 60 Gbps, which has to be significantly reduced by the Data Acquisition System. For the data reduction the hit information of the surrounding Silicon strip Vertex Detector (SVD) is utilized to define so-called Regions of Interest (ROI). Only hit information of the pixels located inside these ROIs are saved. The ROIs for the Pixel Detector (PXD) are computed by reconstructing track segments from SVD data and back extrapolation to the PXD. A data reduction of up to a factor of 10 is intended to be achieved by this design. All the necessary processing stages, the receiving and multiplexing of the data from the SVD on 48 optical fibers, the track reconstruction and the definition of the ROIs, will be performed by the Data Concentrator. The planned hardware design is based on a distributed set of Advanced Mezzanine Cards (AMC) each equipped with a Field Programmable Gate Array (FPGA) chip and 4 optical transceivers. In this talk, the hardware and the FPGA-based tracking algorithm is introduced with some preliminary simulation results. In addition, the acquisition and pre-processing of the SVD data are discussed. The presentation concludes with an outlook on a distributed tracking design.

  5. Spatial and vertex resolution studies on the ATLAS Pixel Detector based on Combined Testbeam 2004 data

    CERN Document Server

    Reisinger, Ingo; Klingenberg, Reiner

    2006-01-01

    This diploma thesis deals with spatial and vertex resolution studies on the ATLAS Pixel detector based on real data taken during the Combined Testbeam period 2004 (17th May - 15th November). For the Combined Testbeam a barrel segment of the ATLAS Detector was build up and tested under real experimental conditions. Several data sets, being recorded during that time, are reconstructed by the ATLAS control framework called ATHENA. The input information for the reconstruction of the particle tracks through the Pixel Detector are the so-called spacepoints. Their uncertainty affects the resolution of the reconstructed particle tracks and thus, also the accuracy of the vertex reconstruction. Since traversing particles deposite their charge mostly (but not compellingly) within more than one pixel, all pixels corresponding to one hit have to be grouped together to a cluster. To compute the spacepoint from the cluster information two different strategies can be performed. The first one is a digital clustering, w...

  6. Development of the MCM-D technique for pixel detector modules

    CERN Document Server

    Grah, Christian

    2005-01-01

    This thesis treats a copper--polymer based thin film technology, the MCM-D technique and its application when building hybrid pixel detector modules. The ATLAS experiment at the LHC will be equipped with a pixel detector system. The basic mechanical units of the pixel detector are multi chip modules. The main components of these modules are: 16 electronic chips, a controller chip and a large sensor tile, featuring more than 46000 sensor cells. MCM-D is a superior technique to build the necessary signal bus system and the power distribution system directly on the active sensor tile. In collaboration with the Fraunhofer Institute for Reliability and Microintegration, IZM, the thin film process is reviewed and enhanced. The multi layer system was designed and optimized for the interconnection system as well as for the 46000 pixel contacts. Laboratory measurements on prototypes prove that complex routing schemes for geometrically optimized single chips are suitable and have negligible influence on the front--end ...

  7. 3D Particle Track Reconstrution in a Single Layer Cadmium-Telluride Hybrid Active Pixel Detector

    CERN Document Server

    Filipenko, Mykhaylo; Anton, Gisela; Michel, Thilo

    2014-01-01

    In the past 20 years the search for neutrinoless double beta decay has driven many developements in all kind of detector technology. A new branch in this field are highly-pixelated semiconductor detectors - such as the CdTe-Timepix detectors. It compromises a cadmium-telluride sensor of 14 mm x 14 mm x 1 mm size with an ASIC which has 256 x 256 pixel of 55 \\textmu m pixel pitch and can be used to obtain either spectroscopic or timing information in every pixel. In regular operation it can provide a 2D projection of particle trajectories; however, three dimensional trajectories are desirable for neutrinoless double beta decay and other applications. In this paper we present a method to obtain such trajectories. The method was developed and tested with simulations that assume some minor modifications to the Timepix ASIC. Also, we were able to test the method experimentally and in the best case achieved a position resolution of about 90 \\textmu m with electrons of 4.4 GeV.

  8. Signal and noise of Diamond Pixel Detectors at High Radiation Fluences

    CERN Document Server

    Tsung, Jieh-Wen; Hügging, Fabian; Kagan, Harris; Krüger, Hans; Wermes, Norbert

    2012-01-01

    CVD diamond is an attractive material option for LHC vertex detectors because of its strong radiation-hardness causal to its large band gap and strong lattice. In particular, pixel detectors operating close to the interaction point profit from tiny leakage currents and small pixel capacitances of diamond resulting in low noise figures when compared to silicon. On the other hand, the charge signal from traversing high energy particles is smaller in diamond than in silicon by a factor of about 2.2. Therefore, a quantitative determination of the signal-to-noise ratio (S/N) of diamond in comparison with silicon at fluences in excess of 10$^{15}$ n$_{eq}$ cm$^{-2}$, which are expected for the LHC upgrade, is important. Based on measurements of irradiated diamond sensors and the FE-I4 pixel readout chip design, we determine the signal and the noise of diamond pixel detectors irradiated with high particle fluences. To characterize the effect of the radiation damage on the materials and the signal decrease, the chang...

  9. Studies on irradiated pixel detectors for the ATLAS IBL and HL-LHC upgrade

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00371978; Gößling, Claus; Pernegger, Heinz

    The constant demand for higher luminosity in high energy physics is the reason for the continuous effort to adapt the accelerators and the experiments. The upgrade program for the experiments and the accelerators at CERN already includes several expansion stages of the Large Hadron Collider (LHC) which will increase the luminosity and the energy of the accelerator. Simultaneously the LHC experiments prepare the individual sub-detectors for the increasing demands in the coming years. Especially the tracking detectors have to cope with fluence levels unprecedented for high energy physics experiments. Correspondingly to the fluence increases the impact of the radiation damage which reduces the life time of the detectors by decreasing the detector performance and efficiency. To cope with this effect new and more radiation hard detector concepts become necessary to extend the life time. This work concentrates on the impact of radiation damage on the pixel sensor technologies to be used in the next upgrade of the ...

  10. Testbeam and laboratory test results of irradiated 3D CMS pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bubna, Mayur [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Purdue University, School of Electrical and Computer Engineering, West Lafayette, IN 47907-1396 (United States); Alagoz, Enver, E-mail: enver.alagoz@cern.ch [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Cervantes, Mayra; Krzywda, Alex; Arndt, Kirk [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Obertino, Margherita; Solano, Ada [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, 10125 Torino (Italy); Dalla Betta, Gian-Franco [INFN Padova (Gruppo Collegato di Trento) (Italy); Dipartimento di Ingegneria e Scienzadella Informazione, Universitá di Trento, I-38123 Povo di Trento (Italy); Menace, Dario; Moroni, Luigi [Istituto Nazionale di Fisica Nucleare, Sezione di Milano Bicocca (Italy); Universitá degli Studi di Milano Bicocca, 20126 Milano (Italy); Uplegger, Lorenzo; Rivera, Ryan [Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States); Osipenkov, Ilya [Texas A and M University, Department of Physics, College Station, TX 77843-4242 (United States); Andresen, Jeff [Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States); Bolla, Gino; Bortoletto, Daniela [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Boscardin, Maurizio [Centro per i Materiali e i Microsistemi Fondazione Bruno Kessler (FBK), Trento, I-38123 Povo di Trento (Italy); Marie Brom, Jean [Strasbourg IPHC, Institut Pluriedisciplinaire Hubert Curien, F-67037 Strasbourg Cedex (France); Brosius, Richard [State University of New York at Buffalo (SUNY), Department of Physics, Buffalo, NY 14260-1500 (United States); Chramowicz, John [Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States); and others

    2013-12-21

    The CMS silicon pixel detector is the tracking device closest to the LHC p–p collisions, which precisely reconstructs the charged particle trajectories. The planar technology used in the current innermost layer of the pixel detector will reach the design limit for radiation hardness at the end of Phase I upgrade and will need to be replaced before the Phase II upgrade in 2020. Due to its unprecedented performance in harsh radiation environments, 3D silicon technology is under consideration as a possible replacement of planar technology for the High Luminosity-LHC or HL-LHC. 3D silicon detectors are fabricated by the Deep Reactive-Ion-Etching (DRIE) technique which allows p- and n-type electrodes to be processed through the silicon substrate as opposed to being implanted through the silicon surface. The 3D CMS pixel devices presented in this paper were processed at FBK. They were bump bonded to the current CMS pixel readout chip, tested in the laboratory, and testbeams carried out at FNAL with the proton beam of 120 GeV/c. In this paper we present the laboratory and beam test results for the irradiated 3D CMS pixel devices. -- Highlights: •Pre-irradiation and post-irradiation electrical properties of 3D sensors and 3D diodes from various FBK production batches were measured and analyzed. •I–T measurements of gamma irradiated diodes were analyzed to understand leakage current generation mechanism in 3D diodes. •Laboratory measurements: signal to noise ratio and charge collection efficiency of 3D sensors before and after irradiation. •Testbeam measurements: pre- and post-irradiation pixel cell efficiency and position resolution of 3D sensors.

  11. High Dynamic Range X-ray Detector Pixel Architectures Utilizing Charge Removal

    CERN Document Server

    Weiss, Joel T; Philipp, Hugh T; Becker, Julian; Chamberlain, Darol; Purohit, Prafull; Tate, Mark W; Gruner, Sol M

    2016-01-01

    Several charge integrating CMOS pixel front-ends utilizing charge removal techniques have been fabricated to extend dynamic range for x-ray diffraction applications at synchrotron sources and x-ray free electron lasers (XFELs). The pixels described herein build on the Mixed Mode Pixel Array Detector (MM-PAD) framework, developed previously by our group to perform high dynamic range imaging. These new pixels boast several orders of magnitude improvement in maximum flux over the MM-PAD, which is capable of measuring a sustained flux in excess of 10$^{8}$ x-rays/pixel/second while maintaining sensitivity to smaller signals, down to single x-rays. To extend dynamic range, charge is removed from the integration node of the front-end amplifier without interrupting integration. The number of times this process occurs is recorded by a digital counter in the pixel. The parameter limiting full well is thereby shifted from the size of an integration capacitor to the depth of a digital counter. The result is similar to t...

  12. Silicon Pixel Detector for the PHENIX experiment at the BNL RHIC

    CERN Document Server

    Ichimiya, Ryo; Akiba, Yasuyuki; Atomssa, Ermias; Chollet, Simon; Drapier, Olivier; En'yo, Hideto; Fujiwara, Kohei; Gastaldi, Franck; de Cassagnac, Raphael Granier; Kasai, Miki; Kurita, Kazuyosi; Kurosawa, Maki; Mannel, Eric J; Ohnishi, Hiroaki; Onuki, Yoshiyuki; Pak, Robart; Pancake, Charles; Sekimoto, Michiko; Shafto, Eugene; Sondheim, Walter; Taketani, Atsushi

    2008-01-01

    PHENIX is one of the major experiments at the Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory. It has been exploring the spin structure of the nucleon utilizing polarized proton-proton collisions and characteristics of the Quark Gluon Plasma (QGP) created in heavy ion collisions. The Silicon Vertex Tracker (VTX) will be implemented in 2010 to enhance physics capabilities. It will be installed very close to the collision point and will cover | \\eta | < 1.2 and | \\phi | ~2{\\pi} by four layers of silicon sensors. Inner two layers are silicon pixel detectors and outer two layers are silicon strip layers. In this paper, the inner silicon pixel detector is reported. We used 200 {\\mu}m thick silicon sensor and readout chip developed for ALICE experiment. As a part of PHENIX detector, it needs to be read out by four times faster from ALICE experiment and to be thin in material to minimize the radiation length. To meet the criteria, the PHENIX silicon pixel detector has been designed an...

  13. Low mass hybrid pixel detectors for the high luminosity LHC upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Gonella, Laura

    2013-10-15

    Reducing material in silicon trackers is of major importance for a good overall detector performance, and poses severe challenges to the design of the tracking system. To match the low mass constraints for trackers in High Energy Physics experiments at high luminosity, dedicated technological developments are required. This dissertation presents three technologies to design low mass hybrid pixel detectors for the high luminosity upgrades of the LHC. The work targets specifically the reduction of the material from the detector services and modules, with novel powering schemes, flip chip and interconnection technologies. A serial powering scheme is prototyped, featuring a new regulator concept, a control and protection element, and AC-coupled data transmission. A modified flip chip technology is developed for thin, large area Front-End chips, and a via last Through Silicon Via process is demonstrated on existing pixel modules. These technologies, their developments, and the achievable material reduction are discussed using the upgrades of the ATLAS pixel detector as a case study.

  14. Comparison of CCD, CMOS and Hybrid Pixel x-ray detectors: detection principle and data quality

    Science.gov (United States)

    Allé, P.; Wenger, E.; Dahaoui, S.; Schaniel, D.; Lecomte, C.

    2016-06-01

    We compare, from a crystallographic point of view, the data quality obtained using laboratory x-ray diffractometers equipped with a Molybdenum micro-source using different detector types: CCD, CMOS and XPAD hybrid pixel. First we give an overview of the working principle of these different detector types with a focus on their principal differences and their impact on the data quality. Then, using the example of an organic crystal, a comparison between the detector systems concerning the raw data statistics, the refinement agreement factors, the deformation electron density maps, and the residual density after multipolar refinement is presented. It is found that the data quality obtained with the XPAD detector is the best, even though the detection efficiency at the Mo energy (17.5 keV) is only 37% due to the Si-sensor layer thickness of 300 μm. Finally, we discuss the latest x-ray detector developments with an emphasis on the sensor material, where replacing Si by another material such as GaAs would yield detection efficiencies close to 100%, up to energies of 40 keV for hybrid pixel detectors.

  15. Energy calibration of the pixels of spectral X-ray detectors.

    Science.gov (United States)

    Panta, Raj Kumar; Walsh, Michael F; Bell, Stephen T; Anderson, Nigel G; Butler, Anthony P; Butler, Philip H

    2015-03-01

    The energy information acquired using spectral X-ray detectors allows noninvasive identification and characterization of chemical components of a material. To achieve this, it is important that the energy response of the detector is calibrated. The established techniques for energy calibration are not practical for routine use in pre-clinical or clinical research environment. This is due to the requirements of using monochromatic radiation sources such as synchrotron, radio-isotopes, and prohibitively long time needed to set up the equipment and make measurements. To address these limitations, we have developed an automated technique for calibrating the energy response of the pixels in a spectral X-ray detector that runs with minimal user intervention. This technique uses the X-ray tube voltage (kVp) as a reference energy, which is stepped through an energy range of interest. This technique locates the energy threshold where a pixel transitions from not-counting (off) to counting (on). Similarly, we have developed a technique for calibrating the energy response of individual pixels using X-ray fluorescence generated by metallic targets directly irradiated with polychromatic X-rays, and additionally γ-rays from (241)Am. This technique was used to measure the energy response of individual pixels in CdTe-Medipix3RX by characterizing noise performance, threshold dispersion, gain variation and spectral resolution. The comparison of these two techniques shows the energy difference of 1 keV at 59.5 keV which is less than the spectral resolution of the detector (full-width at half-maximum of 8 keV at 59.5 keV). Both techniques can be used as quality control tools in a pre-clinical multi-energy CT scanner using spectral X-ray detectors.

  16. Design optimization of Pixel Structure for α-Si based uncooled Infrared detector

    Directory of Open Access Journals (Sweden)

    Sudha Gupta

    2013-12-01

    Full Text Available In this paper authors present the design and simulation results achieved for pixel structure of amorphous Si (α-Si based bolometer array. Most uncooled IR detectors in the world are based on VOx material. But this is not a standard material in IC technology and has many inherent disadvantages. The α-Si, an alternative material with high TCR is becoming as popular. However, large TCR values, in this material are achieved only in films of high resistivity. To achieve TCR value more than 2.5%/K, α-Si film resistivity is ~ 80 ohms-cm. This gives rise to very large pixel resistance of the order of 100 Mega ohms depending upon the design of the leg structure. This high pixel resistance causes very large noise and hence lower sensitivity. If leg width or membrane thickness is increased in order to reduce the pixel resistance, then this results in higher thermal conductance which also decreases sensitivity. To overcome this problem, pixel structure is so designed that within a pixel, only part of the electrical conduction is through α-Si and rest is through metal. Simulation using Coventorware software has been done to optimize pixel resistance as well as thermal conductance through legs so that maximum sensitivity could be obtained. Optimization is also carried out in order to reduce sensitivity of pixel resistance to variation in material resistivity.Defence Science Journal, 2013, 63(6, pp.581-588, DOI:http://dx.doi.org/10.14429/dsj.63.5758

  17. MTF Issues in Small-Pixel-Pitch Planar Quantum IR Detectors

    Science.gov (United States)

    Gravrand, O.; Baier, N.; Ferron, A.; Rochette, F.; Berthoz, J.; Rubaldo, L.; Cluzel, R.

    2014-08-01

    The current trend in quantum infrared (IR) detector development is the design of very small-pixel-pitch large arrays. From the previous 30 μm pitch, the standard pixel pitch today is 15 μm and is expected to decrease to 12 μm in the next few years. Furthermore, focal-plane arrays (FPAs) with pixel pitch as small as 10 μm have been demonstrated. Such ultrasmall-pixel pitches are very small compared with the typical length ruling the electrical characteristics of the absorbing materials, namely the minority-carrier diffusion length. As an example, for low-doped n-type HgCdTe or InSb material, this diffusion length is on the order of 30 μm to 50 μm, i.e., three to five times the targeted pixel pitches. This has strong consequences for the modulation transfer function (MTF) of planar structures, where the lateral extension of the photodiode is limited by diffusion. For such aspect ratios, the self-confinement of neighboring diodes may not be efficient enough to maintain an optimal MTF. Therefore, this issue has to be addressed to take full advantage of the pixel pitch reduction in terms of image resolution. The aim of this work is to investigate the evolution of the MTF of HgCdTe and InSb FPAs when decreasing the pixel pitch below 15 μm. Both experimental measurements and finite-element simulations are used to discuss this issue. Different scenarios are compared, namely deep mesa etch between pixels, internal drift, surface recombination, and thin absorbing layers.

  18. Vectors and submicron precision: redundancy and 3D stacking in silicon pixel detectors

    CERN Document Server

    Heijne, E H M; Wong, W; Idarraga, J; Visser, J; Jakubek, J; Leroy, C; Turecek, D; Visschers, J; Pospisil, S; Ballabriga, R; Vykydal, Z; Vermeulen, J; Plackett, R; Heijne, E H M; Llopart, X; Boltje, D; Campbell, M

    2010-01-01

    Measurements are shown of GeV pions and muons in two 300 mu m thick, Si Medipix pixel detector assemblies that are stacked on top of each other, with a 25 mu m thick brass foil in between. In such a radiation imaging semiconductor matrix with a large number of pixels along the particle trail, one can determine local space vectors for the particle trajectory instead of points. This improves pattern recognition and track reconstruction, especially in a crowded environment. Stacking of sensor planes is essential for resolving directional ambiguities. Signal charge sharing can be employed for measuring positions with submicron precision. In the measurements one notices accompanying `delta' electrons that emerge outside the particle trail, far beyond the boundaries of the 55 mu m pixel cells. The frequency of such corrupted position measurements is similar to one per 2.5mm of traversed Si.

  19. Modeling and analysis of hybrid pixel detector deficiencies for scientific applications

    Science.gov (United States)

    Fahim, Farah; Deptuch, Grzegorz W.; Hoff, James R.; Mohseni, Hooman

    2015-08-01

    Semiconductor hybrid pixel detectors often consist of a pixellated sensor layer bump bonded to a matching pixelated readout integrated circuit (ROIC). The sensor can range from high resistivity Si to III-V materials, whereas a Si CMOS process is typically used to manufacture the ROIC. Independent, device physics and electronic design automation (EDA) tools are used to determine sensor characteristics and verify functional performance of ROICs respectively with significantly different solvers. Some physics solvers provide the capability of transferring data to the EDA tool. However, single pixel transient simulations are either not feasible due to convergence difficulties or are prohibitively long. A simplified sensor model, which includes a current pulse in parallel with detector equivalent capacitor, is often used; even then, spice type top-level (entire array) simulations range from days to weeks. In order to analyze detector deficiencies for a particular scientific application, accurately defined transient behavioral models of all the functional blocks are required. Furthermore, various simulations, such as transient, noise, Monte Carlo, inter-pixel effects, etc. of the entire array need to be performed within a reasonable time frame without trading off accuracy. The sensor and the analog front-end can be modeling using a real number modeling language, as complex mathematical functions or detailed data can be saved to text files, for further top-level digital simulations. Parasitically aware digital timing is extracted in a standard delay format (sdf) from the pixel digital back-end layout as well as the periphery of the ROIC. For any given input, detector level worst-case and best-case simulations are performed using a Verilog simulation environment to determine the output. Each top-level transient simulation takes no more than 10-15 minutes. The impact of changing key parameters such as sensor Poissonian shot noise, analog front-end bandwidth, jitter due to

  20. Modeling and Analysis of Hybrid Pixel Detector Deficiencies for Scientific Applications

    Energy Technology Data Exchange (ETDEWEB)

    Fahim, Farah [Northwestern U. (main); Deptuch, Grzegorz W. [Fermilab; Hoff, James R. [Fermilab; Mohseni, Hooman [Northwestern U. (main)

    2015-08-28

    Semiconductor hybrid pixel detectors often consist of a pixellated sensor layer bump bonded to a matching pixelated readout integrated circuit (ROIC). The sensor can range from high resistivity Si to III-V materials, whereas a Si CMOS process is typically used to manufacture the ROIC. Independent, device physics and electronic design automation (EDA) tools are used to determine sensor characteristics and verify functional performance of ROICs respectively with significantly different solvers. Some physics solvers provide the capability of transferring data to the EDA tool. However, single pixel transient simulations are either not feasible due to convergence difficulties or are prohibitively long. A simplified sensor model, which includes a current pulse in parallel with detector equivalent capacitor, is often used; even then, spice type top-level (entire array) simulations range from days to weeks. In order to analyze detector deficiencies for a particular scientific application, accurately defined transient behavioral models of all the functional blocks are required. Furthermore, various simulations, such as transient, noise, Monte Carlo, inter-pixel effects, etc. of the entire array need to be performed within a reasonable time frame without trading off accuracy. The sensor and the analog front-end can be modeling using a real number modeling language, as complex mathematical functions or detailed data can be saved to text files, for further top-level digital simulations. Parasitically aware digital timing is extracted in a standard delay format (sdf) from the pixel digital back-end layout as well as the periphery of the ROIC. For any given input, detector level worst-case and best-case simulations are performed using a Verilog simulation environment to determine the output. Each top-level transient simulation takes no more than 10-15 minutes. The impact of changing key parameters such as sensor Poissonian shot noise, analog front-end bandwidth, jitter due to

  1. The Shunt-LDO regulator to power the upgraded ATLAS pixel detector

    CERN Document Server

    Gonella, L; Hügging, F; Krüger, H; Wermes, N

    2012-01-01

    The shunt-LDO regulator is a new regulator concept which combines a shunt and a Low Drop-Out (LDO) regulator. Designed as an improved shunt regulator to match the needs of serially powered detector systems, it can also be used as a pure LDO regulator for general application in powering schemes requiring linear regulation. The flexibility of the design makes the shunt-LDO regulator a good candidate for use in the powering schemes envisaged for the upgrades of the ATLAS pixel detector. Two shunt-LDO regulators integrated in the prototype of the next ATLAS pixel front-end chip, the FE-I4A, are used to demonstrate the feasibility of the proposed powering solutions.

  2. ATLAS-TPX: a two-layer pixel detector setup for neutron detection and radiation field characterization

    Science.gov (United States)

    Bergmann, B.; Caicedo, I.; Leroy, C.; Pospisil, S.; Vykydal, Z.

    2016-10-01

    A two-layer pixel detector setup (ATLAS-TPX), designed for thermal and fast neutron detection and radiation field characterization is presented. It consists of two segmented silicon detectors (256 × 256 pixels, pixel pitch 55 μm, thicknesses 300 μm and 500 μm) facing each other. To enhance the neutron detection efficiency a set of converter layers is inserted in between these detectors. The pixelation and the two-layer design allow a discrimination of neutrons against γs by pattern recognition and against charged particles by using the coincidence and anticoincidence information. The neutron conversion and detection efficiencies are measured in a thermal neutron field and fast neutron fields with energies up to 600 MeV. A Geant4 simulation model is presented, which is validated against the measured detector responses. The reliability of the coincidence and anticoincidence technique is demonstrated and possible applications of the detector setup are briefly outlined.

  3. Status of the ATLAS Pixel Detector at the LHC and its performance after three years of operation

    CERN Document Server

    Andreazza, A; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experi- ment at the Large Hadron Collider at CERN, providing high-resolution mea- surements of charged particle tracks in the high radiation environment close to the collision region. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. After three years of operation the detector performance is excellent: 96% of the pixels are opera- tional, at 3500 e threshold noise occupancy and efficiency exceed the design specification. The effect of radiation on the silicon sensor is measured and compared with model of radiation damage.

  4. A DC-DC converter based powering scheme for the upgrade of the CMS pixel detector

    Science.gov (United States)

    Feld, L.; Karpinski, W.; Klein, K.; Merz, J.; Sammet, J.; Wlochal, M.

    2011-11-01

    Around 2016, the pixel detector of the CMS experiment will be upgraded. The amount of current that has to be provided to the front-end electronics is expected to increase by a factor of two. Since the space available for cables is limited, this would imply unacceptable power losses in the currently installed supply cables. Therefore it is foreseen to place DC-DC converters close to the front-end electronics, allowing the provision of power at higher voltages, thereby facilitating the supply of the required currents with the present cable plant. This conference report introduces the foreseen powering scheme of the pixel upgrade. For the first time, system tests have been conducted with pixel barrel sensor modules, radiation tolerant DC-DC converters and the full power supply chain of the pixel detector. In addition, studies of the stability of different powering schemes under various conditions are summarized. In particular the impact of large and fast load variations, which are related to the bunch structure of the LHC beam, has been studied.

  5. Firmware development and testing of the ATLAS Pixel Detector / IBL ROD card

    Science.gov (United States)

    Gabrielli, A.; Backhaus, M.; Balbi, G.; Bindi, M.; Chen, S. P.; Falchieri, D.; Flick, T.; Hauck, S.; Hsu, S. C.; Kretz, M.; Kugel, A.; Lama, L.; Travaglini, R.; Wensing, M.

    2015-03-01

    The ATLAS Experiment is reworking and upgrading systems during the current LHC shut down. In particular, the Pixel detector has inserted an additional inner layer called the Insertable B-Layer (IBL). The Readout-Driver card (ROD), the Back-of-Crate card (BOC), and the S-Link together form the essential frontend data path of the IBL's off-detector DAQ system. The strategy for IBL ROD firmware development was three-fold: keeping as much of the Pixel ROD datapath firmware logic as possible, employing a complete new scheme of steering and calibration firmware, and designing the overall system to prepare for a future unified code version integrating IBL and Pixel layers. Essential features such as data formatting, frontend-specific error handling, and calibration are added to the ROD data path. An IBL DAQ test bench using a realistic front-end chip model was created to serve as an initial framework for full offline electronic system simulation. In this document, major firmware achievements concerning the IBL ROD data path implementation, test on the test bench and ROD prototypes, will be reported. Recent Pixel collaboration efforts focus on finalizing hardware and firmware tests for the IBL. The plan is to approach a complete IBL DAQ hardware-software installation by the end of 2014.

  6. Development of high data readout rate pixel module and detector hybridization at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Sergio Zimmermann et al.

    2001-03-20

    This paper describes the baseline design and a variation of the pixel module to handle the data rate required for the BTeV experiment at Fermilab. The present prototype has shown good electrical performance characteristics. Indium bump bonding is proven to be capable of successful fabrication at 50 micron pitch on real detectors. For solder bumps at 50 micron pitch, much better results have been obtained with the fluxless PADS processed detectors. The results are adequate for our needs and our tests have validated it as a viable technology.

  7. Development of pixel detectors for the IBL and HL-LHC ATLAS experiment upgrade

    CERN Document Server

    Baselga Bacardit, Marta

    2016-03-18

    This thesis presents the development of advanced silicon technology detectors fabricated at CNM-Barcelona for High Energy Physics (HEP) experiments. The pixel size of the tracking silicon detectors for the upgrade of the HL-LHC will have to decrease in size in order to enhance the resolution in position for the measurements and they need to have lower occupancy for the electronics. The future experiments at CERN will cope with fuences up to 2 x 10^^16 neq/cm2, and the smaller 3D silicon detectors will have less trapping of the electron-holes generated in the bulk leading to a better performance under high radiation environment. This thesis studies silicon detectors fabricated at CNM-Barcelona applied to HEP experiments with two different kinds of novel technologies: 3D and Low Gain Avalanche Detectors (LGAD). The 3D detectors make it possible to reduce the size of the depleted region inside the detector and to work at lower voltages, whereas the LGAD detectors have an intrinsic gain which increases the collec...

  8. Testing, installation and development of hardware and software components for the forward pixel detector of CMS

    CERN Document Server

    Florez Bustos, Carlos Andres

    2007-01-01

    The LHC (Large Hadron Collider) will be the particle accelerator with the highest collision energy ever. CMS (Compact Muon Solenoid) is one of the two largest experiments at the LHC. A main goal of CMS is to elucidate the electroweak symmetry breaking and determine if the Higgs mechanism is responsible for it. The pixel detector in CMS is the closest detector to the interaction point and is part of the tracker system. This thesis presents four different projects related to the forward pixel detector, performed as part of the testing and development of its hardware and software components. It presents the methods, implementation and results for the data acquisition and installation of the detector control system at the Meson Test Beam Facility of Fermilab for the beam test of the detector; the study of the C.A.E.N power supply and the multi service cable; the layout of the test stands for the assembly of the half-disk and half-service cylinder and the development of a software interface to the data acquisition...

  9. The CT-PPS tracking system with 3D pixel detectors

    Science.gov (United States)

    Ravera, F.

    2016-11-01

    The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) detector will be installed in Roman pots (RP) positioned on either side of CMS, at about 210 m from the interaction point. This detector will measure leading protons, allowing detailed studies of diffractive physics and central exclusive production in standard LHC running conditions. An essential component of the CT-PPS apparatus is the tracking system, which consists of two detector stations per arm equipped with six 3D silicon pixel-sensor modules, each read out by six PSI46dig chips. The front-end electronics has been designed to fulfill the mechanical constraints of the RP and to be compatible as much as possible with the readout chain of the CMS pixel detector. The tracking system is currently under construction and will be installed by the end of 2016. In this contribution the final design and the expected performance of the CT-PPS tracking system is presented. A summary of the studies performed, before and after irradiation, on the 3D detectors produced for CT-PPS is given.

  10. Development of a detector control system for the serially powered ATLAS pixel detector at the HL-LHC

    Energy Technology Data Exchange (ETDEWEB)

    Puellen, Lukas

    2015-02-10

    In the years around 2020 the LHC will be upgraded to the HL-LHC. In terms of this upgrade, the ATLAS detector will also be upgraded. This also includes the pixel detector, the innermost of the sub-detectors in ATLAS. Thereby the powering concept of the pixel detector will be changed to reduce the material budget of the detector. From individual powering of each detector module, the concept changes to serial powering, where all modules of a powering group are connected in series. This change makes the development of a new detector control system (DCS) mandatory. Therefore, a new concept for the ATLAS pixel DCS is being developed at the University of Wuppertal. This concept is split into three paths: a safety path, a control path, and a diagnostics path. The safety path is a hard wired interlock system. The concept of this system will not differ significantly, compared to the interlock system of the current detector. The diagnostics path is embedded into the optical data read-out of the detector and will be used for detector tuning with high precision and granularity. The control path supervises the detector and provides a user interface to the hardware components. A concept for this path, including a prototype and proof-of-principle studies, has been developed in terms of this thesis. The control path consists of the DCS network, a read-out and controlling topology created by two types of ASICs: the DCS controller and the DCS chip. These ASICs measure and control all values, necessary for a safe detector operation in situ. This reduces the number of required cables and hence the material budget of the system. For the communication between these ASICs, two very fault tolerant bus protocols have been chosen: CAN bus carries data from the DCS computers, outside of the detector, to the DCS controllers at the edge of the pixel detector. For the communication between the DCS controller and the DCS chip, which is located close to each detector module, an enhanced I2C

  11. dE/dx measurement in the ATLAS Pixel Detector and its use for particle identification

    CERN Document Server

    The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector provides a measurement of the charge deposited by each track crossing it. This note presents a study of how this information can be used to identify low beta particles. This study uses hits recorded in the 7 TeV proton-proton collisions during the 2010 run period and the corresponding Monte Carlo simulation. The track reconstruction has been done in the standard ATLAS software environment.

  12. Calibration status and plans for the charge integrating JUNGFRAU pixel detector for SwissFEL

    Science.gov (United States)

    Redford, S.; Bergamaschi, A.; Brückner, M.; Cartier, S.; Dinapoli, R.; Ekinci, Y.; Fröjdh, E.; Greiffenberg, D.; Mayilyan, D.; Mezza, D.; Mozzanica, A.; Rajeev, R.; Ramilli, M.; Ruder, C.; Schädler, L.; Schmitt, B.; Shi, X.; Thattil, D.; Tinti, G.; Zhang, J.

    2016-11-01

    JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector under development for photon science applications at free electron laser and synchrotron facilities. In particular, JUNGFRAU detectors will equip the Aramis end stations of SwissFEL, an X-ray free electron laser currently under construction at the Paul Scherrer Institut in Villigen, Switzerland. JUNGFRAU has been designed specifically to meet the challenges of photon science at XFELs, including high frame rates, single photon sensitivity in combination with a high dynamic range, vacuum compatibility and tilable modules. This has resulted in a charge integrating detector with three dynamically adjusting gains, a low noise of 55 ENC RMS, readout speeds in excess of 2 kHz, single photon sensitivity down to 2 keV (with a signal to noise ratio of 10) and a dynamic range covering four orders of magnitude at 12 keV. Each JUNGFRAU module consists of eight chips of 256 × 256 pixels, each 75 × 75 μm2 in size. The chips are arranged in 2 × 4 formation and bump-bonded to a single silicon sensor 320 μm thick, resulting in an active area of approximately 4 × 8 cm2 per module. Multi-module vacuum compatible systems comprising up to 16 Mpixels (32 modules) will be used at SwissFEL. The design of SwissFEL and the JUNGFRAU system for the Aramis end station A will be introduced, together with results from early prototypes and a characterisation using the first batch of final JUNGFRAU modules. Plans and first results of the pixel-by-pixel calibration will also be shown. The vacuum compatibility of the JUNGFRAU module is demonstrated for the first time.

  13. High-dynamic-range coherent diffractive imaging: ptychography using the mixed-mode pixel array detector

    Energy Technology Data Exchange (ETDEWEB)

    Giewekemeyer, Klaus, E-mail: klaus.giewekemeyer@xfel.eu [European XFEL GmbH, Hamburg (Germany); Philipp, Hugh T. [Cornell University, Ithaca, NY (United States); Wilke, Robin N. [Georg-August-Universität Göttingen, Göttingen (Germany); Aquila, Andrew [European XFEL GmbH, Hamburg (Germany); Osterhoff, Markus [Georg-August-Universität Göttingen, Göttingen (Germany); Tate, Mark W.; Shanks, Katherine S. [Cornell University, Ithaca, NY (United States); Zozulya, Alexey V. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Salditt, Tim [Georg-August-Universität Göttingen, Göttingen (Germany); Gruner, Sol M. [Cornell University, Ithaca, NY (United States); Cornell University, Ithaca, NY (United States); Kavli Institute of Cornell for Nanoscience, Ithaca, NY (United States); Mancuso, Adrian P. [European XFEL GmbH, Hamburg (Germany)

    2014-08-07

    The advantages of a novel wide dynamic range hard X-ray detector are demonstrated for (ptychographic) coherent X-ray diffractive imaging. Coherent (X-ray) diffractive imaging (CDI) is an increasingly popular form of X-ray microscopy, mainly due to its potential to produce high-resolution images and the lack of an objective lens between the sample and its corresponding imaging detector. One challenge, however, is that very high dynamic range diffraction data must be collected to produce both quantitative and high-resolution images. In this work, hard X-ray ptychographic coherent diffractive imaging has been performed at the P10 beamline of the PETRA III synchrotron to demonstrate the potential of a very wide dynamic range imaging X-ray detector (the Mixed-Mode Pixel Array Detector, or MM-PAD). The detector is capable of single photon detection, detecting fluxes exceeding 1 × 10{sup 8} 8-keV photons pixel{sup −1} s{sup −1}, and framing at 1 kHz. A ptychographic reconstruction was performed using a peak focal intensity on the order of 1 × 10{sup 10} photons µm{sup −2} s{sup −1} within an area of approximately 325 nm × 603 nm. This was done without need of a beam stop and with a very modest attenuation, while ‘still’ images of the empty beam far-field intensity were recorded without any attenuation. The treatment of the detector frames and CDI methodology for reconstruction of non-sensitive detector regions, partially also extending the active detector area, are described.

  14. Study on thermal annealing of cadmium zinc telluride (CZT) crystals

    Energy Technology Data Exchange (ETDEWEB)

    Yang, G.; Bolotnikov, A.E.; Fochuk, P.M.; Camarda, G.S.; Cui, Y.; Hossain, A.; Kim, K.; Horace, J.; McCall, B.; Gul, R.; Xu, L.; Kopach, O.V.; and James, R.B.

    2010-08-01

    Cadmium Zinc Telluride (CZT) has attracted increasing interest with its promising potential as a room-temperature nuclear-radiation-detector material. However, different defects in CZT crystals, especially Te inclusions and dislocations, can degrade the performance of CZT detectors. Post-growth annealing is a good approach potentially to eliminate the deleterious influence of these defects. At Brookhaven National Laboratory (BNL), we built up different facilities for investigating post-growth annealing of CZT. Here, we report our latest experimental results. Cd-vapor annealing reduces the density of Te inclusions, while large temperature gradient promotes the migration of small-size Te inclusions. Simultaneously, the annealing lowers the density of dislocations. However, only-Cd-vapor annealing decreases the resistivity, possibly reflecting the introduction of extra Cd in the lattice. Subsequent Te-vapor annealing is needed to ensure the recovery of the resistivity after removing the Te inclusions.

  15. The color of X-rays: Spectral X-ray computed tomography using energy sensitive pixel detectors

    NARCIS (Netherlands)

    Schioppa, E.J.

    2014-01-01

    Energy sensitive X-ray imaging detectors are produced by connecting a semiconductor sensor to a spectroscopic pixel readout chip. In this thesis, the applicability of such detectors to X-ray Computed Tomography (CT) is studied. A prototype Medipix based silicon detector is calibrated using X-ray flu

  16. Investigating the Inverse Square Law with the Timepix Hybrid Silicon Pixel Detector: A CERN [at] School Demonstration Experiment

    Science.gov (United States)

    Whyntie, T.; Parker, B.

    2013-01-01

    The Timepix hybrid silicon pixel detector has been used to investigate the inverse square law of radiation from a point source as a demonstration of the CERN [at] school detector kit capabilities. The experiment described uses a Timepix detector to detect the gamma rays emitted by an [superscript 241]Am radioactive source at a number of different…

  17. Prototypes and system test stands for the Phase 1 upgrade of the CMS pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, S., E-mail: satoshi@fnal.gov

    2016-09-21

    The CMS pixel phase-1 upgrade project replaces the current pixel detector with an upgraded system with faster readout electronics during the extended year-end technical stop of 2016/2017. New electronics prototypes for the system have been developed, and tests in a realistic environment for a comprehensive evaluation are needed. A full readout test stand with either the same hardware as used in the current CMS pixel detector or the latest prototypes of upgrade electronics has been built. The setup enables the observation and investigation of a jitter increase in the data line associated with trigger rate increases. This effect is due to the way in which the clock and trigger distribution is implemented in CMS. A new prototype of the electronics with a PLL based on a voltage controlled quartz crystal oscillator (QPLL), which works as jitter filter, in the clock distribution path was produced. With the test stand, it was confirmed that the jitter increase is not seen with the prototype, and also good performance was confirmed at the expected detector operation temperature (−20 °C).

  18. System test and noise performance studies at the ATLAS pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Weingarten, J.

    2007-09-15

    The central component of the ATLAS Inner Tracker is the pixel detector. It consists of three barrel layers and three disk-layers in the end-caps in both forward directions. The innermost barrel layer is mounted at a distance of about 5 cm from the interaction region. With its very high granularity, truly two-dimensional hit information, and fast readout it is well suited to cope with the high densities of charged tracks, expected this close to the interaction region. The huge number of readout channels necessitates a very complex services infrastructure for powering, readout and safety. After a description of the pixel detector and its services infrastructure, key results from the system test at CERN are presented. Furthermore the noise performance of the pixel detector, crucial for high tracking and vertexing efficiencies, is studied. Measurements of the single-channel random noise are presented together with studies of common mode noise and measurements of the noise occupancy using a random trigger generator. (orig.)

  19. Prototypes and system test stands for the Phase 1 upgrade of the CMS pixel detector

    Science.gov (United States)

    Hasegawa, S.

    2016-09-01

    The CMS pixel phase-1 upgrade project replaces the current pixel detector with an upgraded system with faster readout electronics during the extended year-end technical stop of 2016/2017. New electronics prototypes for the system have been developed, and tests in a realistic environment for a comprehensive evaluation are needed. A full readout test stand with either the same hardware as used in the current CMS pixel detector or the latest prototypes of upgrade electronics has been built. The setup enables the observation and investigation of a jitter increase in the data line associated with trigger rate increases. This effect is due to the way in which the clock and trigger distribution is implemented in CMS. A new prototype of the electronics with a PLL based on a voltage controlled quartz crystal oscillator (QPLL), which works as jitter filter, in the clock distribution path was produced. With the test stand, it was confirmed that the jitter increase is not seen with the prototype, and also good performance was confirmed at the expected detector operation temperature (-20 °C).

  20. A 65 nm CMOS analog processor with zero dead time for future pixel detectors

    Science.gov (United States)

    Gaioni, L.; Braga, D.; Christian, D. C.; Deptuch, G.; Fahim, F.; Nodari, B.; Ratti, L.; Re, V.; Zimmerman, T.

    2017-02-01

    Next generation pixel chips at the High-Luminosity (HL) LHC will be exposed to extremely high levels of radiation and particle rates. In the so-called Phase II upgrade, ATLAS and CMS will need a completely new tracker detector, complying with the very demanding operating conditions and the delivered luminosity (up to 5×1034 cm-2 s-1 in the next decade). This work is concerned with the design of a synchronous analog processor with zero dead time developed in a 65 nm CMOS technology, conceived for pixel detectors at the HL-LHC experiment upgrades. It includes a low noise, fast charge sensitive amplifier featuring a detector leakage compensation circuit, and a compact, single ended comparator that guarantees very good performance in terms of channel-to-channel dispersion of threshold without needing any pixel-level trimming. A flash ADC is exploited for digital conversion immediately after the charge amplifier. A thorough discussion on the design of the charge amplifier and the comparator is provided along with an exhaustive set of simulation results.

  1. Applications of pixellated GaAs X-ray detectors in a synchrotron radiation beam

    CERN Document Server

    Watt, J; Campbell, M; Mathieson, K; Mikulec, B; O'Shea, V; Passmore, M S; Schwarz, C; Smith, K M; Whitehill, C

    2001-01-01

    Hybrid semiconductor pixel detectors are being investigated as imaging devices for radiography and synchrotron radiation beam applications. Based on previous work in the CERN RD19 and the UK IMPACT collaborations, a photon counting GaAs pixel detector (PCD) has been used in an X-ray powder diffraction experiment. The device consists of a 200 mu m thick SI-LEC GaAs detector patterned in a 64*64 array of 170 mu m pitch square pixels, bump-bonded to readout electronics operating in single photon counting mode. Intensity peaks in the powder diffraction pattern of KNbO/sub 3/ have been resolved and compared with results using the standard scintillator, and a PCD predecessor (the Omega 3). The PCD shows improved speed, dynamic range, 2-D information and comparable spatial resolution to the standard scintillator based systems. It also overcomes the severe dead time limitations of the Omega 3 by using a shutter based acquisition mode. A brief demonstration of the possibilities of the system for dental radiography and...

  2. Applications of pixellated GaAs X-ray detectors in a synchrotron radiation beam

    Energy Technology Data Exchange (ETDEWEB)

    Watt, J. E-mail: j.watt@physics.gla.ac.uk; Bates, R.; Campbell, M.; Mathieson, K.; Mikulec, B.; O' Shea, V.; Passmore, M-S.; Schwarz, C.; Smith, K.M.; Whitehill, C

    2001-03-11

    Hybrid semiconductor pixel detectors are being investigated as imaging devices for radiography and synchrotron radiation beam applications. Based on previous work in the CERN RD19 and the UK IMPACT collaborations, a photon counting GaAs pixel detector (PCD) has been used in an X-ray powder diffraction experiment. The device consists of a 200 {mu}m thick SI-LEC GaAs detector patterned in a 64x64 array of 170 {mu}m pitch square pixels, bump-bonded to readout electronics operating in single photon counting mode. Intensity peaks in the powder diffraction pattern of KNbO{sub 3} have been resolved and compared with results using the standard scintillator, and a PCD predecessor (the {omega}3). The PCD shows improved speed, dynamic range, 2-D information and comparable spatial resolution to the standard scintillator based systems. It also overcomes the severe dead time limitations of the {omega}3 by using a shutter based acquisition mode. A brief demonstration of the possibilities of the system for dental radiography and image processing are given, showing a marked reduction in patient dose and dead time compared with film.

  3. The electro-mechanical integration of the NA62 GigaTracker time tagging pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Morel, M; Kluge, A; Rinella, G Aglieri; Ceccucci, A; Daguin, J; Fiorini, M; Kaplon, J; Noy, M; Perktold, L; Petagna, P; Riedler, P [CERN, CH-1211 Geneva 23 (Switzerland); Carassiti, V [INFN Ferrara, Via Saragat 1, 44100 Ferrara (Italy); Jarron, P; Marchetto, F [INFN Torino, Via P. Giurial 1, 10125 Torino (Italy); Mapelli, A; Nuessle, G, E-mail: michel.morel@cern.ch [Universite Catholique de Louvain, 1348 Louvain-la-Neuve (Belgium)

    2010-12-15

    The NA62 GigaTracker is a low mass time tagging hybrid pixel detector operating in a beam with a particle rate of 750 MHz. It consists of three stations with a sensor size of 60 x 27mm{sup 2} containing 18000 pixels, each 300 x 300{mu}m{sup 2}. The active area is connected to a matrix of 2 x 5 pixel ASICs, which time tag the arrival of the particles with a binning of 100 ps. The detector operates in vacuum at -20 to 0{sup 0}C and the material budget per station must be below 0.5% X{sub 0}. Due to the high radiation environment of 2 x 10{sup 14} 1 MeV neutron equivalent cm{sup -2}/yr{sup -1} it is planned to exchange the detector modules regularly. The low material budget, cooling requirements and the request for easy module access has driven the electro-mechanical integration of the GigaTracker, which is presented in this paper.

  4. Atomic Layer Deposition (ALD) grown thin films for ultra-fine pitch pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Härkönen, J. [Helsinki Institute of Physics, CMS Upgrade Project, Helsinki (Finland); Ott, J. [Helsinki Institute of Physics, CMS Upgrade Project, Helsinki (Finland); Laboratory of Radio Chemistry, University of Helsinki (Finland); Mäkelä, M. [Laboratory of Inorganic Chemistry, University of Helsinki (Finland); Arsenovich, T.; Gädda, A.; Peltola, T. [Helsinki Institute of Physics, CMS Upgrade Project, Helsinki (Finland); Tuovinen, E. [Helsinki Institute of Physics, CMS Upgrade Project, Helsinki (Finland); VTT Technical Research Centre of Finland, Microsystem and Nanoelectronics (Finland); Luukka, P.; Tuominen, E. [Helsinki Institute of Physics, CMS Upgrade Project, Helsinki (Finland); Junkes, A. [Institute for Experimental Physics, University of Hamburg (Germany); Niinistö, J.; Ritala, M. [Laboratory of Inorganic Chemistry, University of Helsinki (Finland)

    2016-09-21

    In this report we cover two special applications of Atomic Layer Deposition (ALD) thin films to solve these challenges of the very small size pixel detectors. First, we propose to passivate the p-type pixel detector with ALD grown Al{sub 2}O{sub 3} field insulator with a negative oxide charge instead of using the commonly adopted p-stop or p-spray technologies with SiO{sub 2}, and second, to use plasma-enhanced ALD grown titanium nitride (TiN) bias resistors instead of the punch through biasing structures. Surface passivation properties of Al{sub 2}O{sub 3} field insulator was studied by Photoconductive Decay (PCD) method and our results indicate that after appropriate annealing Al{sub 2}O{sub 3} provides equally low effective surface recombination velocity as thermally oxidized Si/SiO{sub 2} interface. Furthermore, with properly designed annealing steps, the TiN thin film resistors can be tuned to have up to several MΩ resistances with a few µm of physical size required in ultra-fine pitch pixel detectors.

  5. Atomic Layer Deposition (ALD) grown thin films for ultra-fine pitch pixel detectors

    Science.gov (United States)

    Härkönen, J.; Ott, J.; Mäkelä, M.; Arsenovich, T.; Gädda, A.; Peltola, T.; Tuovinen, E.; Luukka, P.; Tuominen, E.; Junkes, A.; Niinistö, J.; Ritala, M.

    2016-09-01

    In this report we cover two special applications of Atomic Layer Deposition (ALD) thin films to solve these challenges of the very small size pixel detectors. First, we propose to passivate the p-type pixel detector with ALD grown Al2O3 field insulator with a negative oxide charge instead of using the commonly adopted p-stop or p-spray technologies with SiO2, and second, to use plasma-enhanced ALD grown titanium nitride (TiN) bias resistors instead of the punch through biasing structures. Surface passivation properties of Al2O3 field insulator was studied by Photoconductive Decay (PCD) method and our results indicate that after appropriate annealing Al2O3 provides equally low effective surface recombination velocity as thermally oxidized Si/SiO2 interface. Furthermore, with properly designed annealing steps, the TiN thin film resistors can be tuned to have up to several MΩ resistances with a few μm of physical size required in ultra-fine pitch pixel detectors.

  6. Fully 3D-Integrated Pixel Detectors for X-Rays

    Energy Technology Data Exchange (ETDEWEB)

    Deptuch, Grzegorz W. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Gabriella, Carini [SLAC National Accelerator Lab., Menlo Park, CA (United States); Enquist, Paul [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Grybos, Pawel [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Holm, Scott [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lipton, Ronald [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Maj, Piotr [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Patti, Robert [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Siddons, David Peter [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Szczygiel, Robert [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Yarema, Raymond [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2016-01-01

    The vertically integrated photon imaging chip (VIPIC1) pixel detector is a stack consisting of a 500-μm-thick silicon sensor, a two-tier 34-μm-thick integrated circuit, and a host printed circuit board (PCB). The integrated circuit tiers were bonded using the direct bonding technology with copper, and each tier features 1-μm-diameter through-silicon vias that were used for connections to the sensor on one side, and to the host PCB on the other side. The 80-μm-pixel-pitch sensor was the direct bonding technology with nickel bonded to the integrated circuit. The stack was mounted on the board using Sn–Pb balls placed on a 320-μm pitch, yielding an entirely wire-bond-less structure. The analog front-end features a pulse response peaking at below 250 ns, and the power consumption per pixel is 25 μW. We successful completed the 3-D integration and have reported here. Additionally, all pixels in the matrix of 64 × 64 pixels were responding on well-bonded devices. Correct operation of the sparsified readout, allowing a single 153-ns bunch timing resolution, was confirmed in the tests on a synchrotron beam of 10-keV X-rays. An equivalent noise charge of 36.2 e- rms and a conversion gain of 69.5 μV/e- with 2.6 e- rms and 2.7 μV/e- rms pixel-to-pixel variations, respectively, were measured.

  7. Prototype imaging Cd-Zn-Te array detector

    Energy Technology Data Exchange (ETDEWEB)

    Bloser, P.F.; Narita, T.; Grindlay, J.E. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Shah, K. [Radiation Monitoring Devices, Inc., Watertown, MA (United States)

    1998-12-31

    The authors describe initial results of their program to develop and test Cd-Zn-Te (CZT) detectors with a pixellated array readout. Their primary interest is in the development of relatively thick CZT detectors for use in astrophysical coded aperture telescopes with response extending over the energy range {approximately}10--600 keV. The coded aperture imaging configuration requires only relatively large area pixels (1--3 mm), whereas the desired high energy response requires detector thicknesses of at least 3--5 mm. They have developed a prototype detector employing a 10 x 10 x 5 mm CZT substrate and 4 x 4 pixel (1.5 mm each) readout with gold metal contacts for the pixels and continuous gold contact for the bias on the opposite detector face. This MSM contact configuration was fabricated by RMD and tested at Harvard for uniformity, efficiency and spatial as well as spectral resolution. The authors have developed an ASIC readout (IDE-VA-1) and analysis system and report results, including {approximately}4% (FWHM) energy resolution at 60 keV. A prototype design for a full imaging detector array is discussed.

  8. Detection of secondary electrons with pixelated hybrid semiconductor detectors; Sekundaerelektronennachweis mit pixelierten hybriden Halbleiterdetektoren

    Energy Technology Data Exchange (ETDEWEB)

    Gebert, Ulrike Sonja

    2011-09-14

    Within the scope of this thesis, secondary electrons were detected with a pixelated semiconductor detector named Timepix. The Timepix detector consists of electronics and a sensor made from a semiconductor material. The connection of sensor and electronics is done for each pixel individually using bump bonds. Electrons with energies above 3 keV can be detected with the sensor. One electron produces a certain amount of electron-hole pairs according to its energy. The charge then drifts along an electric field to the pixel electronics, where it induces an electric signal. Even without a sensor it is possible to detect an electric signal from approximately 1000 electrons directly in the pixel electronics. Two different detector systems to detect secondary electrons using the Timepix detector were investigated during this thesis. First of all, a hybrid photon detector (HPD) was used to detect single photoelectrons. The HPD consists of a vacuum vessel with an entrance window and a cesium iodine photocathode at the inner surface of the window. Photoelectrons are released from the photocathode by incident light and are accelerated in an electric field towards the Timepix detector, where the point of interaction and the arrival time of the electron is determined. With a proximity focusing setup, a time resolution of 12 ns (with an acceleration voltage of 20 kV between photocathode and Timepix detector) was obtained. The HPD examined in this thesis showed a strong dependence of the dark rate form the acceleration voltage and the pressure in the vacuum vessel. At a pressure of few 10{sup -5} mbar and an acceleration voltage of 20 kV, the dark rate was about 800 Hz per mm{sup 2} area of the read out photocathode. One possibility to reduce the dark rate is to identify ion feedback events. With a slightly modified setup it was possible to reduce the dark rate to 0.5 Hz/mm{sup 2}. To achieve this, a new photocathode was mounted in a shorter distance to the detector. The

  9. An investigation of performance characteristics of a pixellated room-temperature semiconductor detector for medical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Guerra, P; Santos, A [Centro de Investigacion Biomedica de Bioningenieria, Biomateriales y Nanomedicina, CEEI-Modulo 3, C/ Maria de Luna, 11, 50018 Zaragoza (United States); Darambara, D G, E-mail: pguerra@ciber-bbn.e [Joint Department of Physics, Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Fulham Road, London SW3 6JJ (United Kingdom)

    2009-09-07

    The operation of any semiconductor detector depends on the movement of the charge carriers, which are created within the material when radiation passes through, as a result of energy deposition. The carrier movement in the bulk semiconductor induces charges on the metal electrodes, and therefore a current on the electrodes and the external circuit. The induced charge strongly depends on the material transport parameters as well as the geometrical dimensions of a pixellated semiconductor detector. This work focuses on the performance optimization in terms of energy resolution, detection efficiency and intrinsic spatial resolution of a room-temperature semiconductor pixellated detector based on CdTe/CdZnTe. It analyses and inter-relates these performance figures for various dimensions of CdTe and CdZnTe detectors and for an energy range spanning from x-ray (25 keV) to PET (511 keV) imaging. Monte Carlo simulations, which integrate a detailed and accurate noise model, are carried out to investigate several CdTe/CdZnTe configurations and to determine possible design specifications. Under the considered conditions, the simulations demonstrate the superiority of the CdZnTe over the CdTe in terms of energy resolution and sensitivity in the photopeak. Further, according to the results, the spatial resolution is maximized at high energies and the energy resolution at low energies, while a reasonable detection efficiency is achieved at high energies, with a 1 x 1 x 6 mm{sup 3} CdZnTe pixellated detector.

  10. Rapid-acquisition myocardial perfusion scintigraphy (MPS) on a novel gamma camera using multipinhole collimation and miniaturized cadmium-zinc-telluride (CZT) detectors: prognostic value and diagnostic accuracy in a 'real-world' nuclear cardiology service.

    Science.gov (United States)

    Chowdhury, F U; Vaidyanathan, S; Bould, M; Marsh, J; Trickett, C; Dodds, K; Clark, T P R; Sapsford, R J; Dickinson, C J; Patel, C N; Thorley, P J

    2014-03-01

    To study the prognostic value of rapid-acquisition adenosine stress-rest myocardial perfusion scintigraphy (MPS) on a gamma camera using multipinhole collimation and cadmium-zinc-telluride (CZT) detectors. The secondary aim was to assess the diagnostic accuracy of the technique compared with invasive coronary angiography. Retrospective analysis of 1109 consecutive patients undergoing MPS in a routine clinical setting on a high-efficiency multipinhole gamma camera. MPS acquisition, performed with a standard injection of 550 MBq of (99m)Tc-tetrofosmin, required a mean (±SD) scanning time of 322 ± 51 s. The hard cardiac event rate at a median (inter-quartile range) follow-up of 624 (552-699) days was 0.4% (95% CI 0.1-1.1) in patients with no significant perfusion abnormality versus 6.8% (95% CI 4.3-10.7%, P MPS of 84% (95% CI 74-91), 79% (95% CI 68-87), 82% (95% CI 72-89), 81% (95% CI 70-89), and 82% (95% CI 73-89), respectively. MPS performed on a CZT solid-state detector camera with multipinhole collimation is an evolutionary development that provides reliable prognostic and diagnostic information, while significantly reducing image acquisition time.

  11. High-dynamic-range coherent diffractive imaging: ptychography using the mixed-mode pixel array detector

    Science.gov (United States)

    Giewekemeyer, Klaus; Philipp, Hugh T.; Wilke, Robin N.; Aquila, Andrew; Osterhoff, Markus; Tate, Mark W.; Shanks, Katherine S.; Zozulya, Alexey V.; Salditt, Tim; Gruner, Sol M.; Mancuso, Adrian P.

    2014-01-01

    Coherent (X-ray) diffractive imaging (CDI) is an increasingly popular form of X-ray microscopy, mainly due to its potential to produce high-resolution images and the lack of an objective lens between the sample and its corresponding imaging detector. One challenge, however, is that very high dynamic range diffraction data must be collected to produce both quantitative and high-resolution images. In this work, hard X-ray ptychographic coherent diffractive imaging has been performed at the P10 beamline of the PETRA III synchrotron to demonstrate the potential of a very wide dynamic range imaging X-ray detector (the Mixed-Mode Pixel Array Detector, or MM-PAD). The detector is capable of single photon detection, detecting fluxes exceeding 1 × 108 8-keV photons pixel−1 s−1, and framing at 1 kHz. A ptychographic reconstruction was performed using a peak focal intensity on the order of 1 × 1010 photons µm−2 s−1 within an area of approximately 325 nm × 603 nm. This was done without need of a beam stop and with a very modest attenuation, while ‘still’ images of the empty beam far-field intensity were recorded without any attenuation. The treatment of the detector frames and CDI methodology for reconstruction of non-sensitive detector regions, partially also extending the active detector area, are described. PMID:25178008

  12. Electrical-modelling, design and simulation of cumulative radiation effects in semiconductor pixels detectors: prospects and limits

    CERN Document Server

    Fourches, Nicolas T; Chipaux, Rémi

    2014-01-01

    Silicon detectors have gained in popularity since silicon became a widely used micro/nanoelectronic semiconductor material. Silicon detectors are used in particle physics as well as imaging for pixel based detecting systems. Over the past twenty years a lot of experimental efforts have been focused on the effects of ionizing and non-ionizing radiation on silicon pixels. Some of this research was done in the framework of high luminosity particle physics experiments, along with radiation hardness studies of basic semiconductors devices. In its simplest form the semiconductor pixel detectors reduce to a PIN or PN structure partially or totally depleted, or in some MOS and APD (Avalanche PhotoDiode) structures. Bulk or surface defects affect considerably transport of free carriers. We propose guidelines for pixel design, which will be tested through a few pixel structures. This design method includes into the design the properties of defects. The electrical properties reduce to parameters, which can be introduced...

  13. Development of a pixel sensor with fine space-time resolution based on SOI technology for the ILC vertex detector

    Science.gov (United States)

    Ono, Shun; Togawa, Manabu; Tsuji, Ryoji; Mori, Teppei; Yamada, Miho; Arai, Yasuo; Tsuboyama, Toru; Hanagaki, Kazunori

    2017-02-01

    We have been developing a new monolithic pixel sensor with silicon-on-insulator (SOI) technology for the International Linear Collider (ILC) vertex detector system. The SOI monolithic pixel detector is realized using standard CMOS circuits fabricated on a fully depleted sensor layer. The new SOI sensor SOFIST can store both the position and timing information of charged particles in each 20×20 μm2 pixel. The position resolution is further improved by the position weighted with the charges spread to multiple pixels. The pixel also records the hit timing with an embedded time-stamp circuit. The sensor chip has column-parallel analog-to-digital conversion (ADC) circuits and zero-suppression logic for high-speed data readout. We are designing and evaluating some prototype sensor chips for optimizing and minimizing the pixel circuit.

  14. Commissioning and Operation of the New CMS Phase-1 Pixel Detector

    CERN Document Server

    Si, Weinan

    2017-01-01

    The Phase-1 upgrade of the CMS pixel detector is built out of four barrel layers (BPix) and three forward disks in each endcap (FPix). It comprises a total of 124M pixel channels in 1,856 modules, and it is designed to withstand instantaneous luminosities of up to $2 \\times 10^{34}$\\,cm$^{-2}$s$^{-1}$. Different parts of the detector were assembled over the last year and later brought to CERN for installation inside the CMS tracker. At various stages during the assembly tests have been performed to ensure that the readout and power electronics and the cooling system meet the design specifications. After tests of the individual components, system tests were performed before the installation inside CMS. In addition to reviewing these tests, we also present results from the final commissioning of the detector in-situ using the central CMS DAQ system. Finally we review results from the initial operation of the detector first with cosmic rays and then with pp collisions.

  15. A new Data Acquisition System for the CMS Phase 1 Pixel Detector

    CERN Document Server

    Kornmayer, Andreas

    2016-01-01

    A new pixel detector will be installed in the CMS experiment during the extended technical stop of the LHC at the beginning of 2017. The new pixel detector, built from four layers in the barrel region and three layers on each end of the forward region, is equipped with upgraded front-end readout electronics, specifically designed to handle the high particle hit rates created in the LHC environment. The DAQ back-end was entirely redesigned to handle the increased number of readout channels, the higher data rates per channel and the new digital data format. Based entirely on the microTCA standard, new front-end controller (FEC) and front-end driver (FED) cards have been developed, prototyped and produced with custom optical link mezzanines mounted on the FC7 AMC and custom firmware. At the same time as the new detector is being assembled, the DAQ system is set up and its integration into the CMS central DAQ system tested by running the pilot blade detector already installed in CMS. This work describes the DAQ s...

  16. Construction and commissioning of the Phase 1 upgrade of the CMS pixel detector

    CERN Document Server

    Bartek, Rachel

    2017-01-01

    The Phase 1 upgrade of the CMS pixel detector, installed by the CMS collaboration during the recent extended end-of-year technical stop, is built out of four barrel layers (BPIX) and three forward disks in each endcap (FPIX). It comprises a total of 124M pixel channels, in 1,856 modules and it is designed to withstand instantaneous luminosities of up to $2 \\rm{x} 10^{34} \\rm{cm}^{-2} \\rm{s}^{-1}$ with increased detector acceptance and additional redundancy for the tracking, while at the same time reducing the material budget. These goals are achieved using a new readout chip and modified powering and readout schemes, one additional tracking layer both in the barrel and in the disks, and new detector supports including a $\\rm{CO}_2$ based evaporative cooling system. Different parts of the detector have been assembled over the last year and later brought to CERN for installation inside the CMS tracker. At various stages during the assembly tests have been performed to ensure that the readout and power electro...

  17. A new data acquisition system for the CMS Phase 1 pixel detector

    Science.gov (United States)

    Kornmayer, A.

    2016-12-01

    A new pixel detector will be installed in the CMS experiment during the extended technical stop of the LHC at the beginning of 2017. The new pixel detector, built from four layers in the barrel region and three layers on each end of the forward region, is equipped with upgraded front-end readout electronics, specifically designed to handle the high particle hit rates created in the LHC environment. The DAQ back-end was entirely redesigned to handle the increased number of readout channels, the higher data rates per channel and the new digital data format. Based entirely on the microTCA standard, new front-end controller (FEC) and front-end driver (FED) cards have been developed, prototyped and produced with custom optical link mezzanines mounted on the FC7 AMC and custom firmware. At the same time as the new detector is being assembled, the DAQ system is set up and its integration into the CMS central DAQ system tested by running the pilot blade detector already installed in CMS. This work describes the DAQ system, integration tests and gives an outline for the activities up to commissioning the final system at CMS in 2017.

  18. Multiplexed Readout for 1000-pixel Arrays of Microwave Kinetic Inductance Detectors

    CERN Document Server

    van Rantwijk, Joris; van Loon, Dennis; Yates, Stephen; Baryshev, Andrey; Baselmans, Jochem

    2015-01-01

    Microwave Kinetic Inductance Detectors (MKIDs) are the most attractive radiation detectors for far-infrared and sub-mm astronomy: They combine ultimate sensitivity with the possibility to create very large detector arrays, in excess of 10 000 pixels. This is possible by reading-out the arrays using RF frequency division multiplexing, which allows multiplexing ratios in excess of 1000 pixels per readout line. We describe a novel readout system for large arrays of MKIDs, operating in a 2 GHz band in the 4-8 GHz range. The readout, which is a combination of a digital front- and back-end and an analog up- and down-converter system, can read out up to 4000 detectors simultaneously with 1 kHz datarate. The system achieves a readout noise power spectral density of -98 dBc/Hz while reading 1000 carriers simultaneously, which scales linear with the number of carriers. We demonstrate that 4000 state-of-the-art Aluminium-NbTiN MKIDs can be read out without deteriorating their intrinsic performance.

  19. The CT-PPS tracking system with 3D pixel detectors

    CERN Document Server

    Ravera, Fabio

    2016-01-01

    The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) detector will be installed in Roman pots (RP) positioned on either side of CMS, at about 200 m from the interaction point. This detector will measure forward leading protons, allowing detailed studies of diffractive physics and central exclusive production in standard LHC running conditions. An essential component of the CT-PPS apparatus is the tracking system, which consists of two detector stations per arm equipped with six 3D silicon pixel-sensor modules, each read out by six PSI46dig chips. The front-end electronics has been designed to fulfill the mechanical constrains of the RP and to be compatible as much as possible with the readout chain of the CMS pixel detector. The tracking system is currently under construction and will be installed by the end of 2016. In this contribution the final design and the expected performance of the CT-PPS tracking system will be presented. A summary of the studies performed, before and after irradiation, on the 3D det...

  20. Three-dimensional cascaded system analysis of a 50 µm pixel pitch wafer-scale CMOS active pixel sensor x-ray detector for digital breast tomosynthesis.

    Science.gov (United States)

    Zhao, C; Vassiljev, N; Konstantinidis, A C; Speller, R D; Kanicki, J

    2017-03-07

    High-resolution, low-noise x-ray detectors based on the complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) technology have been developed and proposed for digital breast tomosynthesis (DBT). In this study, we evaluated the three-dimensional (3D) imaging performance of a 50 µm pixel pitch CMOS APS x-ray detector named DynAMITe (Dynamic Range Adjustable for Medical Imaging Technology). The two-dimensional (2D) angle-dependent modulation transfer function (MTF), normalized noise power spectrum (NNPS), and detective quantum efficiency (DQE) were experimentally characterized and modeled using the cascaded system analysis at oblique incident angles up to 30°. The cascaded system model was extended to the 3D spatial frequency space in combination with the filtered back-projection (FBP) reconstruction method to calculate the 3D and in-plane MTF, NNPS and DQE parameters. The results demonstrate that the beam obliquity blurs the 2D MTF and DQE in the high spatial frequency range. However, this effect can be eliminated after FBP image reconstruction. In addition, impacts of the image acquisition geometry and detector parameters were evaluated using the 3D cascaded system analysis for DBT. The result shows that a wider projection angle range (e.g.  ±30°) improves the low spatial frequency (below 5 mm(-1)) performance of the CMOS APS detector. In addition, to maintain a high spatial resolution for DBT, a focal spot size of smaller than 0.3 mm should be used. Theoretical analysis suggests that a pixelated scintillator in combination with the 50 µm pixel pitch CMOS APS detector could further improve the 3D image resolution. Finally, the 3D imaging performance of the CMOS APS and an indirect amorphous silicon (a-Si:H) thin-film transistor (TFT) passive pixel sensor (PPS) detector was simulated and compared.