Author
U. Parzefall
Bio: U. Parzefall is an academic researcher from University of Freiburg. The author has contributed to research in topics: Detector & Radiation hardening. The author has an hindex of 12, co-authored 18 publications receiving 429 citations.
Papers
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KEK1, University of Liverpool2, University of Glasgow3, Santa Cruz Institute for Particle Physics4, Academy of Sciences of the Czech Republic5, University of Cambridge6, Brookhaven National Laboratory7, Lancaster University8, Jožef Stefan Institute9, University of Geneva10, Stony Brook University11, Charles University in Prague12, University of Sheffield13, Spanish National Research Council14, University of New Mexico15, University of Tsukuba16, University of Freiburg17, Hamamatsu Photonics18
21 Apr 2011-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this article, the authors developed a highly radiation-tolerant n-in-p silicon microstrip sensor for very high radiation environments such as in the Super Large Hadron Collider.
Abstract: We have developed a novel and highly radiation-tolerant n-in-p silicon microstrip sensor for very high radiation environments such as in the Super Large Hadron Collider. The sensors are designed for a fluence of 1×1015 neq/cm2 and are fabricated from p-type, FZ, 6 in. (150 mm) wafers onto which we lay out a single 9.75 cm×9.75 cm large-area sensor and several 1 cm×1 cm miniature sensors with various n-strip isolation structures. By evaluating the sensors both pre- and post-irradiation by protons and neutrons, we find that the full depletion voltage evolves to approximately 800 V and that the n-strip isolation depends on the p+ concentration. In addition, we characterize the interstrip resistance, interstrip capacitance and the punch-through-protection (PTP) voltage. The first fabrication batch allowed us to identify the weak spots in the PTP and the stereo strip layouts. By understanding the source of the weakness, the mask was modified accordingly. After modification, the follow-up fabrication batches and the latest fabrication of about 30 main sensors and associated miniature sensors have shown good performance, with no sign of microdischarge up to 1000 V.
79 citations
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TL;DR: In this paper, the authors measured the inclusive and dijet production cross-sections for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of root s = 7 TeV, using the ATLAS detector at the LHC.
Abstract: The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of root s = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb(-1). The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 -dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m(jj) < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured b (b) over bar -dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.
72 citations
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11 Dec 2011-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this article, the signal and the noise of irradiated n-inp and p-in-n 3D silicon strip detectors are compared, and the influence of different temperatures on signal and noise is investigated and results of annealing measurements are reported.
Abstract: Silicon detectors in 3D technology are a candidate for applications in environments requiring an extreme radiation hardness, as in the innermost layers of the detectors at the proposed High-Luminosity LHC. In 3D detectors, the electrodes are made of columns etched into the silicon perpendicular to the surface. This leads to higher electric fields, a smaller depletion voltage and a reduced trapping probability of the charge carriers compared to standard planar detectors. In this article, the signal and the noise of irradiated n-in-p and p-in-n 3D silicon strip detectors are compared. The devices under test have been irradiated up to a fluence of 2×1016 1 MeV neutron equivalent particles per square centimetre (neq/cm2), which corresponds to the fluence expected for the inner pixel detector layers at the High-Luminosity LHC. A relative charge collection efficiency of approximately 70% was obtained even after the highest irradiation fluence with both detector types. The influence of different temperatures on the signal and the noise is investigated and results of annealing measurements are reported.
40 citations
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University of Tsukuba1, University of Liverpool2, University of Glasgow3, University of California, Santa Cruz4, Academy of Sciences of the Czech Republic5, University of Cambridge6, Brookhaven National Laboratory7, Lancaster University8, University of Ljubljana9, University of Geneva10, Stony Brook University11, Charles University in Prague12, University of Sheffield13, Spanish National Research Council14, University of New Mexico15, KEK16, University of Freiburg17
21 Apr 2011-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this article, the authors developed n+-in-p, p-bulk and n-readout, microstrip sensors, fabricated by Hamamatsu Photonics, as a non-inverting radiation hard silicon detector for the ATLAS tracker upgrade at the super-LHC (sLHC) proposed facility.
Abstract: We are developing n+-in-p, p-bulk and n-readout, microstrip sensors, fabricated by Hamamatsu Photonics, as a non-inverting radiation hard silicon detector for the ATLAS tracker upgrade at the super-LHC (sLHC) proposed facility. The bulk radiation damage after neutron and proton irradiations is characterized with the leakage current, charge collection and full depletion voltage. The detectors should provide acceptable signal, signal-to-noise ratio exceeding 15, after the integrated luminosity of 6000 fb−1, which is twice the sLHC integrated luminosity goal.
38 citations
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University of California, Santa Cruz1, University of Liverpool2, University of Glasgow3, Academy of Sciences of the Czech Republic4, University of Cambridge5, Brookhaven National Laboratory6, Lancaster University7, University of Ljubljana8, University of Geneva9, Stony Brook University10, Charles University in Prague11, University of Sheffield12, Spanish National Research Council13, University of New Mexico14, University of Tsukuba15, KEK16, University of Freiburg17
21 Apr 2011-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this paper, the authors developed n+inp, p-bulk and n-readout, microstrip sensors as a non-inverting radiation hard silicon detector for the ATLAS Tracker Upgrade at the super LHC experiment.
Abstract: We are developing n+-in-p, p-bulk and n-readout, microstrip sensors as a non-inverting radiation hard silicon detector for the ATLAS Tracker Upgrade at the super LHC experiment. The surface radiation damages of the sensors fabricated by Hamamatsu Photonics are characterized on the interstrip capacitance, interstrip resistance and punch-through protection evolution. The detector should provide acceptable strip isolation, exceeding the input impedance of the signal readout chip ∼1 kΩ, after the integrated luminosity of 6 ab−1, which is twice the luminosity goal.
31 citations
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TL;DR: In this paper, the ATLAS experiment is described as installed in i ts experimental cavern at point 1 at CERN and a brief overview of the expec ted performance of the detector is given.
Abstract: This paper describes the ATLAS experiment as installed in i ts experimental cavern at point 1 at CERN. It also presents a brief overview of the expec ted performance of the detector.
2,798 citations
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01 Jan 2007
TL;DR: In this paper, a preliminary set of updated NLO parton distributions and their uncertainties determined from CCFR and NuTeV dimuon cross sections are presented, along with additional jet data from HERA and the Tevatron.
Abstract: We present a preliminary set of updated NLO parton distributions. For the first time we have a quantitative extraction of the strange quark and antiquark distributions and their uncertainties determined from CCFR and NuTeV dimuon cross sections. Additional jet data from HERA and the Tevatron improve our gluon extraction. Lepton asymmetry data and neutrino structure functions improve the flavour separation, particularly constraining the down quark valence distribution.
1,288 citations
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University of Savoy1, Université Paris-Saclay2, CERN3, Czech Technical University in Prague4, Technische Universität München5, University of Belgrade6, University of Santiago de Compostela7, University of Tokyo8, École des mines de Nantes9, Nanjing University of Science and Technology10, University of Cape Town11, Saint Petersburg State University12, Federico Santa María Technical University13, Utrecht University14, Duke University15, University of Bergen16, University of Auvergne17, Texas A&M University18, Iowa State University19, Bielefeld University20, Heidelberg University21, University of Grenoble22, Tata Institute of Fundamental Research23, Kent State University24, University of Lyon25, Goethe University Frankfurt26, Los Alamos National Laboratory27, University of California, Davis28, Lawrence Livermore National Laboratory29, Central China Normal University30, Tsinghua University31
TL;DR: In this paper, the authors review the study of open heavy-flavour and quarkonium production in high-energy hadronic collisions, as tools to investigate fundamental aspects of Quantum Chromodynamics, from the proton and nucleus structure at high energy to deconfinement and the properties of the Quark-Gluon Plasma.
Abstract: This report reviews the study of open heavy-flavour and quarkonium production in high-energy hadronic collisions, as tools to investigate fundamental aspects of Quantum Chromodynamics, from the proton and nucleus structure at high energy to deconfinement and the properties of the Quark–Gluon Plasma. Emphasis is given to the lessons learnt from LHC Run 1 results, which are reviewed in a global picture with the results from SPS and RHIC at lower energies, as well as to the questions to be addressed in the future. The report covers heavy flavour and quarkonium production in proton–proton, proton–nucleus and nucleus–nucleus collisions. This includes discussion of the effects of hot and cold strongly interacting matter, quarkonium photoproduction in nucleus–nucleus collisions and perspectives on the study of heavy flavour and quarkonium with upgrades of existing experiments and new experiments. The report results from the activity of the SaporeGravis network of the I3 Hadron Physics programme of the European Union 7
$$\mathrm{th}$$
Framework Programme.
535 citations
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TL;DR: In this paper, the authors present predictions for a variety of single-inclusive observables that stem from the production of charm and bottom quark pairs at the 7 TeV LHC.
Abstract: We present predictions for a variety of single-inclusive observables that stem from the production of charm and bottom quark pairs at the 7 TeV LHC. They are obtained within the FONLL semi-analytical framework, and with two "Monte Carlo + NLO" approaches, MC@NLO and POWHEG. Results are given for final states and acceptance cuts that are as close as possible to those used by experimental collaborations and, where feasible, are compared to LHC data.
511 citations
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TL;DR: This paper categorizes the work on wearable flexible sensors according to the materials used for designing the system, the network protocols, and different types of activities that were being monitored.
Abstract: This paper provides a review on some of the significant research work done on wearable flexible sensors (WFSs). Sensors fabricated with the flexible materials have been attached to a person along with the embedded system to monitor a parameter and transfer the significant data to the monitoring unit for the further analyses. The use of wearable sensors has played a quite important role to monitor the physiological parameters of a person to minimize any malfunctioning happening in the body. This paper categorizes the work according to the materials used for designing the system, the network protocols, and different types of activities that were being monitored. The challenges faced by the current sensing systems and future opportunities for the WFSs regarding its market values are also briefly explained in this paper.
368 citations