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2. Comparing and Combining Measurement-Based and Driven-Dissipative Entanglement Stabilization*

Author

Yehan Liu, Katrina Sliwa, Robert Schoelkopf, Michael Hatridge, Nissim Ofek, Anirudh Narla, Shyam Shankar, Luigi Frunzio, and Michel Devoret

Subjects
Quantum Physics, Computer science, Condensed Matter - Superconductivity, Physics, QC1-999, General Physics and Astronomy, FOS: Physical sciences, TheoryofComputation_GENERAL, Quantum entanglement, 01 natural sciences, 010305 fluids & plasmas, Superconductivity (cond-mat.supr-con), 0103 physical sciences, Dissipative system, Computer Science::Programming Languages, Statistical physics, 010306 general physics, Error detection and correction, Quantum Physics (quant-ph), Protocol (object-oriented programming), Computer Science::Databases, Quantum computer
Abstract

We demonstrate and contrast two approaches to the stabilization of qubit entanglement by feedback. Our demonstration is built on a feedback platform consisting of two superconducting qubits coupled to a cavity which are measured by a nearly-quantum-limited measurement chain and controlled by high-speed classical logic circuits. This platform is used to stabilize entanglement by two nominally distinct schemes: a "passive" reservoir engineering method and an "active" correction based on conditional parity measurements. In view of the instrumental roles that these two feedback paradigms play in quantum error-correction and quantum control, we directly compare them on the same experimental setup. Further, we show that a second layer of feedback can be added to each of these schemes, which heralds the presence of a high-fidelity entangled state in realtime. This "nested" feedback brings about a marked entanglement fidelity improvement without sacrificing success probability., Comment: 40 pages, 12 figures

Published
2016

3. Extending the lifetime of a quantum bit with error correction in superconducting circuits

Author

Reinier Heeres, Yehan Liu, Mazyar Mirrahimi, Brian Vlastakis, Michel Devoret, Steven Girvin, Luigi Frunzio, Zaki Leghtas, Philip Reinhold, Robert Schoelkopf, Andrei Petrenko, Nissim Ofek, and Liang Jiang

Subjects
Multidisciplinary, Computer science, 02 engineering and technology, Transmon, 021001 nanoscience & nanotechnology, 01 natural sciences, Phase qubit, Quantum error correction, Quantum state, Qubit, Quantum mechanics, 0103 physical sciences, Quantum information, 010306 general physics, 0210 nano-technology, Error detection and correction, Algorithm, Quantum computer
Abstract

Quantum error correction (QEC) can overcome the errors experienced by qubits1 and is therefore an essential component of a future quantum computer. To implement QEC, a qubit is redundantly encoded in a higher-dimensional space using quantum states with carefully tailored symmetry properties. Projective measurements of these parity-type observables provide error syndrome information, with which errors can be corrected via simple operations2. The ‘break-even’ point of QEC—at which the lifetime of a qubit exceeds the lifetime of the constituents of the system—has so far remained out of reach3. Although previous works have demonstrated elements of QEC4–16, they primarily illustrate the signatures or scaling properties of QEC codes rather than test the capacity of the system to preserve a qubit over time. Here we demonstrate a QEC system that reaches the break-even point by suppressing the natural errors due to energy loss for a qubit logically encoded in superpositions of Schrodinger-cat states17 of a superconducting resonator18–21. We implement a full QEC protocol by using real-time feedback to encode, monitor naturally occurring errors, decode and correct. As measured by full process tomography, without any post-selection, the corrected qubit lifetime is 320 microseconds, which is longer than the lifetime of any of the parts of the system: 20 times longer than the lifetime of the transmon, about 2.2 times longer than the lifetime of an uncorrected logical encoding and about 1.1 longer than the lifetime of the best physical qubit (the |0〉f and |1〉f Fock states of the resonator). Our results illustrate the benefit of using hardware-efficient qubit encodings rather than traditional QEC schemes. Furthermore, they advance the field of experimental error correction from confirming basic concepts to exploring the metrics that drive system performance and the challenges in realizing a fault-tolerant system.

Published
2016

4. Using thermoforming capacity of metallic glasses to produce multimaterials

Author

Michel Suéry, J. Ragani, S. Valque, A. Volland, Yehan Liu, Sébastien Gravier, and Jean-Jacques Blandin

Subjects
Zirconium, Amorphous metal, Materials science, Mechanical Engineering, Metals and Alloys, Forming processes, chemistry.chemical_element, Casting, law.invention, chemistry, Mechanics of Materials, law, Materials Chemistry, Crystallization, Composite material, Supercooling, Thermal analysis, Thermoforming
Abstract

In addition to casting, thermoforming is a particularly interesting way to produce components in bulk metallic glasses since large strains can be achieved when the BMGs are deformed in their supercooled liquid region. The experimental window (temperature, time) in which high temperature forming can be carried out is directly related to the crystallization resistance of the glass. Such forming windows have been identified for zirconium based bulk metallic glasses thanks to thermal analysis and compression tests in the supercooled liquid region. Based on this identification, the thermoforming capacity of the studied glasses was used to produce multimaterials associating metallic glasses with conventional metallic alloys. Two processes have been preferentially investigated (co-extrusion and co-pressing) and the interface quality of the elaborated multi materials was studied.

Published
2010
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5. Characterizing entanglement of an artificial atom and a cavity cat state with Bell’s inequality

Author

Michel Devoret, Michael Hatridge, Yehan Liu, Luigi Frunzio, Zaki Leghtas, K. Sliwa, Luyan Sun, Jacob Blumoff, Mazyar Mirrahimi, Brian Vlastakis, Robert Schoelkopf, Nissim Ofek, Liang Jiang, Andrei Petrenko, Departments of Applied Physics [New Haven], Yale University [New Haven], QUANTum Information Circuits (QUANTIC), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Inria Paris-Rocquencourt, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Pierre et Marie Curie - Paris 6 (UPMC)-MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), and Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Mines Paris - PSL (École nationale supérieure des mines de Paris)

Subjects
Physics, Bell state, Multidisciplinary, Cat state, General Physics and Astronomy, General Chemistry, Quantum entanglement, Quantum Physics, 01 natural sciences, Multipartite entanglement, General Biochemistry, Genetics and Molecular Biology, Article, 010305 fluids & plasmas, Local hidden variable theory, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], [MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph], Quantum mechanics, 0103 physical sciences, Bell test experiments, GHZ experiment, 010306 general physics, Quantum teleportation
Abstract

The Schrodinger's cat thought experiment highlights the counterintuitive concept of entanglement in macroscopically distinguishable systems. The hallmark of entanglement is the detection of strong correlations between systems, most starkly demonstrated by the violation of a Bell inequality. No violation of a Bell inequality has been observed for a system entangled with a superposition of coherent states, known as a cat state. Here we use the Clauser–Horne–Shimony–Holt formulation of a Bell test to characterize entanglement between an artificial atom and a cat state, or a Bell-cat. Using superconducting circuits with high-fidelity measurements and real-time feedback, we detect correlations that surpass the classical maximum of the Bell inequality. We investigate the influence of decoherence with states up to 16 photons in size and characterize the system by introducing joint Wigner tomography. Such techniques demonstrate that information stored in superpositions of coherent states can be extracted efficiently, a crucial requirement for quantum computing with resonators., Qubit-cavity entanglement can be used for quantum information processing and for investigating the quantum-to-classical transition with high control. Here, the authors characterize the entanglement between an artificial atom and a cat state and its susceptibility to decoherence through Bell test witnesses.

Published
2015
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6. Influence of thermomechanical processing on the superelastic properties of a Ni-rich Nitinol shape memory alloy

Author

L. Debove, Laurent Orgéas, P. Comte-Gaz, Denis Favier, Arnaud Sandel, Yehan Liu, Colin, Anne-Marie, Laboratoire de Mécanique des Contacts et des Structures [Villeurbanne] (LaMCoS), Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Fabrication, Materials science, Mechanical Engineering, Metallurgy, Alloy, technology, industry, and agriculture, Shape-memory alloy, engineering.material, Condensed Matter Physics, Mechanics of Materials, Nickel titanium, engineering, Thermomechanical processing, General Materials Science, Deformation (engineering), ComputingMilieux_MISCELLANEOUS, Tensile testing
Abstract

Ni-rich NiTi shape memory alloys usually undergo a series of thermomechanical treatment in their production and component fabrication processes. Comprehension of property changes and microstructural evolutions induced by these treatments is essential for quality control and improvement of these materials. The effect of controlled ageing for prolonged times (of the order of several hours) has been extensively investigated in the literature. This study investigates the effect of actual production processes of NiTi tubing, which often involve thermomechanical treatment for multiple periods of short durations and which are typical of industrial production routines of devices like stents, on the transformation and deformation behaviour of a Ti–50.8 at%Ni alloy. Evolution of the properties is characterized by DSC measurements and by tensile testing at 310 K.

Published
2006
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7. Modeling of microwave near-field coupling between grounded electric wire and patch antenna

Author

Rajkumar, E. R., Ravelo, B., Mohamed BENSETTI, Yehan Liu, Supélec Sciences des Systèmes (E3S), Ecole Supérieure d'Electricité - SUPELEC (FRANCE), Douesnard, Stéphanie, BENSETTI, Mohamed, Institut de Recherche en Systèmes Electroniques Embarqués (IRSEEM), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-École Supérieure d’Ingénieurs en Génie Électrique (ESIGELEC), Laboratoire Génie électrique et électronique de Paris (GeePs), and Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI]Engineering Sciences [physics], [SPI] Engineering Sciences [physics], [SPI.NRJ]Engineering Sciences [physics]/Electric power, ComputingMilieux_MISCELLANEOUS, [SPI.NRJ] Engineering Sciences [physics]/Electric power
Abstract

International audience

Published
2014

8. Resistance welding of NiTi shape memory alloy tubes

Author

Hervé Louche, Vincent Delobelle, Patrick Delobelle, Denis Favier, Yehan Liu, Laboratoire sols, solides, structures - risques [Grenoble] (3SR), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Joseph Fourier - Grenoble 1 (UJF)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), School of Mechanical and Chemical Engineering (University of Wester Australia), The University of Western Australia (UWA), ThermoMécanique des Matériaux (ThM2), Laboratoire de Mécanique et Génie Civil (LMGC), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire sols, solides, structures - risques [Grenoble] ( 3S-R ), Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut National Polytechnique de Grenoble ( INPG ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ), MECANIQUE APPLIQUEE, Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies ( FEMTO-ST ), Université de Technologie de Belfort-Montbeliard ( UTBM ) -Ecole Nationale Supérieure de Mécanique et des Microtechniques ( ENSMM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ) -Université de Technologie de Belfort-Montbeliard ( UTBM ) -Ecole Nationale Supérieure de Mécanique et des Microtechniques ( ENSMM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), School of Mechanical and Chemical Engineering ( University of Wester Australia ), The University of Western Australia ( UWA ), ThermoMécanique des Matériaux ( ThM2 ), Laboratoire de Mécanique et Génie Civil ( LMGC ), and Université de Montpellier ( UM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Montpellier ( UM ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
Materials science, [ SPI.MECA ] Engineering Sciences [physics]/Mechanics [physics.med-ph], 02 engineering and technology, Welding, Electric resistance welding, 01 natural sciences, Industrial and Manufacturing Engineering, law.invention, law, 0103 physical sciences, Ultimate tensile strength, Composite material, 010302 applied physics, Metallurgy, Metals and Alloys, technology, industry, and agriculture, Shape-memory alloy, Nanoindentation, respiratory system, [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph], 021001 nanoscience & nanotechnology, Microstructure, Computer Science Applications, Nickel titanium, Modeling and Simulation, Pseudoelasticity, Ceramics and Composites, 0210 nano-technology
Abstract

International audience; Resistance welding is studied as a technique to join NiTi shape memory alloy thin-walled tubes. Properties of the welded metal are compared to those of the base metal by means of differential scanning calorimetry measurements, microstructure observations and nanoindentation tests. Transformation behaviour, microstructure and mechanical properties of the joint are significantly affected by the welding process. The effect of post-welding thermomechanical treatment is studied. After solution treatment followed by ageing, the transformation behaviour of the joint and of the initial material is almost identical. Strength of the joint is analysed by means of tensile and compression tests performed on as welded and heat treated tubes. This study proves that resistance welding is a feasible technique to create complex structures with low density and high reversible elasticity.

Published
2013
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9. Indication of Reactorν¯eDisappearance in the Double Chooz Experiment

Author

A. Cucoanes, F. Ardellier, M. Obolensky, M. Dracos, H. de Kerret, D. Shrestha, R. Svoboda, C. L. Jones, J. Maeda, I. Ostrovskiy, R. Santorelli, A. Tonazzo, C. Jollet, M. Franke, A. F. Barbosa, T. Hayakawa, J. Tm. Goon, I. Gil-Botella, Daniel M. Kaplan, G. Keefer, J.V. Dawson, R. Milincic, Tobias Lachenmaier, C. E. Lane, B. Guillon, J. Reichenbacher, J. Spitz, M. Worcester, N. Tamura, M. Dierckxsens, M. Cribier, J. Haser, G. Mention, H. Miyata, M. Kuze, K. Nakajima, C. Langbrandtner, J. Hartnell, Z. Sun, Christian Buck, H. P. Lima, M. Cerrada, C. Aberle, Yasushi Nagasaka, S. Cormon, Muriel Fallot, T. Classen, E. Kemp, J. Busenitz, Janet Conrad, E. Damon, S. Perasso, S. Roth, C. N. Maesano, C. Mariani, Th. A. Mueller, E. Caden, A. Onillon, W. Potzel, T. Kawasaki, D. Dietrich, Matthew L Strait, A. Hatzikoutelis, M. D. Skorokhvatov, Michael Wurm, H. Watanabe, A. Bernstein, Florian Kaether, Y. Kibe, J. Felde, Z. Djurcic, A. Osborn, A. Milzstajn, D. Franco, C. Palomares, K. Zbiri, D. E. Reyna, S. M. Fernandes, Yu. Efremenko, M. Bongrand, Ying Sun, Alain Letourneau, L. Bezrukhov, T.J.C. Bezerra, U. Schwan, Kazuhiro Terao, Yuri Kamyshkov, F. von Feilitzsch, Caren Hagner, R. Gama, Amanda Porta, H. H. Trinh Thi, T. Miletic, P. Perrin, A. Meregaglia, D. Kryn, J. Maricic, Christopher Wiebusch, J. M. LoSecco, David Lhuillier, Lothar Oberauer, Bayarto Lubsandorzhiev, B. White, P.-J. Chang, Masaki Ishitsuka, E. Falk, M. Elnimr, Thierry Lasserre, V. V. Sinev, M. Göger-Neff, H. Furuta, G. A. Horton-Smith, M. C. Goodman, F. Yermia, V. Durand, Lindley Winslow, Anatael Cabrera, F. X. Hartmann, E. Yanovitch, Y. Sakamoto, H. A. Rubin, Michael Hofmann, B. Reinhold, F. Sato, M. H. Shaevitz, Luis González, Nathaniel Bowden, Thomas Schwetz, E. Conover, H. Tabata, J. C. dos Anjos, V. Zimmer, L.N. Kalousis, M. Toups, I. M. Pepe, A. Baxter, A. Stüken, Steven Dazeley, R. Carr, D. Greiner, Yoshio Abe, L. Camilleri, Lydie Giot, M. V. d'Agostino, J. Martino, Sebastian Wagner, Manfred Lindner, Antoine Collin, E. Blucher, M. Röhling, S. Schönert, Y. Endo, P. Pfahler, M. Fechner, P. Chimenti, A.V. Etenko, T. Matsubara, J. M. López-Castanõ, I. Stancu, S. J. M. Peeters, T. Akiri, Stefan Schoppmann, D. Mckee, T. Haruna, Yehan Liu, T. Konno, A. Remoto, F. Suekane, P. Novella, T. Sumiyoshi, D. Motta, T. Hara, A. Stahl, J. L. Sida, R. Queval, M. Bergevin, J. Jochum, K. Crum, A. J. Franke, S. V. Sukhotin, J. I. Crespo-Anadón, E. Smith, N. Haag, S. Lucht, and C. Veyssiere

Subjects
NOνA, Physics, Particle physics, Muon, 010308 nuclear & particles physics, General Physics and Astronomy, Flux, Daya Bay Reactor Neutrino Experiment, CHOOZ, 7. Clean energy, 01 natural sciences, Nuclear physics, 0103 physical sciences, High Energy Physics::Experiment, Neutrino, Nuclear Experiment, 010306 general physics, Neutrino oscillation, Electron neutrino
Abstract

The Double Chooz experiment presents an indication of reactor electron antineutrino disappearance consistent with neutrino oscillations. An observed-to-predicted ratio of events of 0.944±0.016(stat)±0.040(syst) was obtained in 101 days of running at the Chooz nuclear power plant in France, with two 4.25GWth reactors. The results were obtained from a single 10m3 fiducial volume detector located 1050 m from the two reactor cores. The reactor antineutrino flux prediction used the Bugey4 flux measurement after correction for differences in core composition. The deficit can be interpreted as an indication of a nonzero value of the still unmeasured neutrino mixing parameter sin⁡22θ13. Analyzing both the rate of the prompt positrons and their energy spectrum, we find sin⁡22θ13=0.086±0.041(stat)±0.030(syst), or, at 90% C.L., 0.017

Published
2012
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10. Design of multi materials combining crystalline and amorphous metallic alloys

Author

J. Ragani, Yehan Liu, Sébastien Gravier, A. Volland, Michel Suéry, Jean-Jacques Blandin, Science et Ingénierie des Matériaux et Procédés (SIMaP), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010302 applied physics, Zirconium, Amorphous metal, Materials science, Mechanical Engineering, Metallurgy, Metals and Alloys, chemistry.chemical_element, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Copper, law.invention, Amorphous solid, chemistry, Mechanics of Materials, law, 0103 physical sciences, Materials Chemistry, Crystallization, 0210 nano-technology, Supercooling, Thermal analysis, Thermoforming
Abstract

International audience; Multi materials, associating zirconium based bulk metallic glasses and crystalline metallic alloys like magnesium alloys or copper are elaborated by co-deformation processing performed in the supercooled liquid regions (SLR) of the bulk metallic glasses. Two processes are investigated: co-extrusion and co-pressing. In the first case, filamentary composites with various designs can be produced whereas in the second case sandwich structures are obtained. The experimental window (temperature, time) in which processing can be carried out is directly related to the crystallisation resistance of the glass which requires getting information about the crystallisation conditions in the selected metallic glasses. Thermoforming windows are identified for the studied BMGs by thermal analysis and compression tests in their SLR. The mechanical properties of the produced multi materials are investigated thanks to specifically developed mechanical devices and the interfaces between the amorphous and the crystalline alloys are characterised.

Published
2012
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11. Application of arbitrary-order Hilbert spectral analysis to passive scalar turbulence

Author

Zhenyuan Lu, François G. Schmitt, Yongxiang Huang, Yehan Liu, Yves Gagne, Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG), Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Nord])

Subjects
History, Turbulence, Mathematical analysis, Structure function, Scalar (mathematics), Reynolds number, Hilbert spectral analysis, 01 natural sciences, 010305 fluids & plasmas, Computer Science Applications, Education, Physics::Fluid Dynamics, symbols.namesake, 0103 physical sciences, symbols, 010306 general physics, Scaling, Microscale chemistry, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, Mathematics
Abstract

International audience; In previous work [Huang et al., PRE 82, 26319, 2010], we found that the passive scalar turbulence field maybe less intermittent than what we believed before. Here we apply the same method, namely arbitrary-order Hilbert spectral analysis, to a passive scalar (temperature) time series with a Taylor's microscale Reynolds number Reλ 3000. We find that with increasing Reynolds number, the discrepancy of scaling exponents between Hilbert ξθ(q) and Kolmogorov-Obukhov-Corrsin (KOC) theory is increasing, and consequently the discrepancy between Hilbert and structure function could disappear at infinite Reynolds number

Published
2011
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12. International Linear Collider Accelerator Physics R&D

Author

Alex Lang, Yehan Liu, Michael Davidsaver, Jason Chang, Michael Kasten, George D Gollin, Will Dluger, Michael Haney, and Perry Chodash

Subjects
Engineering, Software, International Linear Collider, Backplane, business.industry, Reference design, Clock rate, Electrical engineering, Fault tolerance, Linux kernel, business, Phase detector
Abstract

ILC work at Illinois has concentrated primarily on technical issues relating to the design of the accelerator. Because many of the problems to be resolved require a working knowledge of classical mechanics and electrodynamics, most of our research projects lend themselves well to the participation of undergraduate research assistants. The undergraduates in the group are scientists, not technicians, and find solutions to problems that, for example, have stumped PhD-level staff elsewhere. The ILC Reference Design Report calls for 6.7 km circumference damping rings (which prepare the beams for focusing) using “conventional” stripline kickers driven by fast HV pulsers. Our primary goal was to determine the suitability of the 16 MeV electron beam in the AO region at Fermilab for precision kicker studies.We found that the low beam energy and lack of redundancy in the beam position monitor system complicated the analysis of our data. In spite of these issues we concluded that the precision we could obtain was adequate to measure the performance and stability of a production module of an ILC kicker, namely 0.5%. We concluded that the kicker was stable to an accuracy of ~2.0% and that we could measure this precision to an accuracy of ~0.5%. Asmore » a result, a low energy beam like that at AO could be used as a rapid-turnaround facility for testing ILC production kicker modules. The ILC timing precision for arrival of bunches at the collision point is required to be 0.1 picosecond or better. We studied the bunch-to-bunch timing accuracy of a “phase detector” installed in AO in order to determine its suitability as an ILC bunch timing device. A phase detector is an RF structure excited by the passage of a bunch. Its signal is fed through a 1240 MHz high-Q resonant circuit and then down-mixed with the AO 1300 MHz accelerator RF. We used a kind of autocorrelation technique to compare the phase detector signal with a reference signal obtained from the phase detector’s response to an event at the beginning of the run. We determined that the device installed in our beam, which was instrumented with an 8-bit 500 MHz ADC, could measure the beam timing to an accuracy of 0.4 picoseconds. Simulations of the device showed that an increase in ADC clock rate to 2 GHz would improve measurement precision by the required factor of four. As a result, we felt that a device of this sort, assuming matters concerning dynamic range and long-term stability can be addressed successfully, would work at the ILC. Cost effective operation of the ILC will demand highly reliable, fault tolerant and adaptive solutions for both hardware and software. The large numbers of subsystems and large multipliers associated with the modules in those subsystems will cause even a strong level of unit reliability to become an unacceptable level of system availability. An evaluation effort is underway to evaluate standards associated with high availability, and to guide ILC development with standard practices and well-supported commercial solutions. One area of evaluation involves the Advanced Telecom Computing Architecture (ATCA) hardware and software. We worked with an ATCA crate, processor monitors, and a small amount of ATCA circuit boards in order to develop a backplane “spy” board that would let us watch the ATCA backplane communications and pursue development of an inexpensive processor monitor that could be used as a physics-driven component of the crate-level controls system. We made good progress, and felt that we had determined a productive direction to extend this work. We felt that we had learned enough to begin designing a workable processor monitor chip if there were to be sufficient interest in ATCA shown by the ILC community. Fault recognition is a challenging issue in the crafting a high reliability controls system. With tens of thousands of independent processors running hundreds of thousands of critical processes, how can the system identify that a problem has arisen and determine the appropriate steps to take to correct, or compensate, for the failure? One possible solution might come through the use of the OpenClovis supervisory system, which runs on Linux processors and allows a select set of processors to monitor the behavior of individual processes and processors in a large, distributed controls network. We found that OpenClovis exhibited an irritating amount of sensitivity to the exact version of the Linux kernel running on the processors, and that it was poorly equipped to help us sort through problems that arose through conflicts so deep in the operating systems of the processors. But once this issue was addressed, we found that it performed as expected, recognizing crashes and process (and processor) failures.« less

Published
2008
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13. Does the threshold representation associated with the autoconversion process matter?

Author

Joyce E. Penner, Yehan Liu, Huan Guo, Atmospheric Science Division [Upton], Brookhaven National Laboratory [Upton, NY] (BNL), U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY), Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor] (AOSS), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, and EGU, Publication

Subjects
Atmospheric Science, Meteorology, 010504 meteorology & atmospheric sciences, 010502 geochemistry & geophysics, 01 natural sciences, lcsh:Chemistry, 0103 physical sciences, Sensitivity (control systems), Critical radius, Statistical physics, Representation (mathematics), 010306 general physics, Physics::Atmospheric and Oceanic Physics, Mathematics, 0105 earth and related environmental sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Smoothness (probability theory), Atmospheric models, [SDU.OCEAN] Sciences of the Universe [physics]/Ocean, Atmosphere, Cloud fraction, lcsh:QC1-999, Distribution (mathematics), lcsh:QD1-999, 13. Climate action, Liquid water path, lcsh:Physics
Abstract

Different ad hoc threshold functions associated with the autoconversion process have been arbitrarily used in atmospheric models. However, it is unclear how these ad hoc functions impact model results. Here systematic investigations of the sensitivities of climatically-important properties: CF (cloud fraction), LWP (liquid water path), and AIE (aerosol indirect effect) to threshold functions have been performed using a 3-D cloud-resolving model. It is found that the effect of threshold representations is larger on instantaneous values than on daily averages; and the effect depends on the percentage of clouds in their transitional stages of converting cloud water to rain water. For both the instantaneous values and daily averages, the sensitivity to the specification of critical radius is more significant than the sensitivity to the "smoothness" of the threshold representation (as embodied in the relative dispersion of droplet size distribution) for drizzling clouds. Moreover, the impact of threshold representations on the AIE is stronger than that on CF and LWP.

Published
2008

14. Geophysical validation of MIPAS-ENVISAT operational ozone data

Author

M. De Mazière, T. E. Kerzenmacher, W. J. Reburn, Jayanarayanan Kuttippurath, C. Piccolo, Yasjka Meijer, Michel Pirre, S. Mikuteit, Valéry Catoire, Gerald Wetzel, Ugo Cortesi, Corinne Vigouroux, C. Keim, Giovanni Bianchini, Kenneth W. Jucks, Costas A. Varotsos, Yehan Liu, Elisa Castelli, Stephen W. Wood, Nicholas B. Jones, C. de Clercq, Jean-Christopher Lambert, Piera Raspollini, I. S. McDermid, Hermann Oelhaf, John Remedios, A. Taddei, H. Kuellmann, Marco Iarlori, T. Steck, Sophie Godin-Beekmann, Thomas Blumenstock, Kelly Chance, Dan Smale, Gianluca Redaelli, F. Mencaraglia, Astrid Bracher, Alison Waterfall, Harjinder Sembhi, P. Demoulin, Fabrizio Ravegnani, G. Y. Liu, Istituto di Fisica Applicata 'Nello Carrara' (IFAC), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Institute for Meteorology and Climate Research (IMK), Karlsruhe Institute of Technology (KIT), Institute of Environmental Physics and Remote Sensing [Bremen] (IUP/IFE), University of Bremen, Istituto di Scienze dell'Atmosfera e del Clima (ISAC), Laboratoire de physique et chimie de l'environnement (LPCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), University of Wollongong [Australia], University of Toronto, CETEMPS, Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), Institute of Atmospheric Physics [Beijing] (IAP), Chinese Academy of Sciences [Beijing] (CAS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), National Institute for Public Health and the Environment [Bilthoven] (RIVM), Department of Atmospheric, Oceanic and Planetary Physics [Oxford] (AOPP), University of Oxford, CCLRC Rutherford Appleton Laboratory (RAL), University of Leicester, National Institute of Water and Atmospheric Research [Wellington] (NIWA), National and Kapodistrian University of Athens (NKUA), Istituto di Fisica Applicata 'Nello Carrara' ( IFAC ), Consiglio Nazionale delle Ricerche [Roma] ( CNR ), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique ( BIRA-IASB ), Institut für Meteorologie und Klimaforschung ( IMK ), Karlsruher Institut für Technologie ( KIT ), Institute of Environmental Physics and Remote Sensing, Universität Bremen, Istituto di Scienze dell'Atmosfera e del Clima ( ISAC ), Laboratoire de physique et chimie de l'environnement ( LPCE ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université d'Orléans ( UO ) -Centre National de la Recherche Scientifique ( CNRS ), Harvard-Smithsonian Center for Astrophysics ( CfA ), Harvard University [Cambridge]-Smithsonian Institution, Service d'aéronomie ( SA ), Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), University of Wollongong, Università degli Studi dell'Aquila [L'Aquila] ( UNIVAQ.IT ), Institute of Atmospheric Physics [Beijing] ( IAP ), Chinese Academy of Sciences [Beijing] ( CAS ), Jet Propulsion Laboratory ( JPL ), NASA-California Institute of Technology ( CALTECH ), National Institute for Public Health and the Environment [Bilthoven] ( RIVM ), Department of Atmospheric, Oceanic and Planetary Physics [Oxford] ( AOPP ), University of Oxford [Oxford], CCLRC Rutherford Appleton Laboratory ( RAL ), National Institute for Water and Air Research Ltd., National and Kapodistrian University of Athens, Consiglio Nazionale delle Ricerche [Roma] (CNR), Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Università degli Studi dell'Aquila (UNIVAQ)

Subjects
[ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, 0211 other engineering and technologies, 02 engineering and technology, Collocation (remote sensing), 01 natural sciences, 7. Clean energy, 010309 optics, Troposphere, lcsh:Chemistry, Data assimilation, Atmospheric composition and structure, Ozone, 0103 physical sciences, ddc:550, Stratosphere, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, Atmospheric sounding, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], lcsh:QC1-999, Trace gas, Depth sounding, Earth sciences, Lidar, [ PHYS.PHYS.PHYS-AO-PH ] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], lcsh:QD1-999, 13. Climate action, Environmental science, lcsh:Physics
Abstract

The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), on-board the European ENVIronmental SATellite (ENVISAT) launched on 1 March 2002, is a middle infrared Fourier Transform spectrometer measuring the atmospheric emission spectrum in limb sounding geometry. The instrument is capable to retrieve the vertical distribution of temperature and trace gases, aiming at the study of climate and atmospheric chemistry and dynamics, and at applications to data assimilation and weather forecasting. MIPAS operated in its standard observation mode for approximately two years, from July 2002 to March 2004, with scans performed at nominal spectral resolution of 0.025 cm−1 and covering the altitude range from the mesosphere to the upper troposphere with relatively high vertical resolution (about 3 km in the stratosphere). Only reduced spectral resolution measurements have been performed subsequently. MIPAS data were re-processed by ESA using updated versions of the Instrument Processing Facility (IPF v4.61 and v4.62) and provided a complete set of level-2 operational products (geo-located vertical profiles of temperature and volume mixing ratio of H2O, O3, HNO3, CH4, N2O and NO2) with quasi continuous and global coverage in the period of MIPAS full spectral resolution mission. In this paper, we report a detailed description of the validation of MIPAS-ENVISAT operational ozone data, that was based on the comparison between MIPAS v4.61 (and, to a lesser extent, v4.62) O3 VMR profiles and a comprehensive set of correlative data, including observations from ozone sondes, ground-based lidar, FTIR and microwave radiometers, remote-sensing and in situ instruments on-board stratospheric aircraft and balloons, concurrent satellite sensors and ozone fields assimilated by the European Center for Medium-range Weather Forecasting. A coordinated effort was carried out, using common criteria for the selection of individual validation data sets, and similar methods for the comparisons. This enabled merging the individual results from a variety of independent reference measurements of proven quality (i.e. well characterized error budget) into an overall evaluation of MIPAS O3 data quality, having both statistical strength and the widest spatial and temporal coverage. Collocated measurements from ozone sondes and ground-based lidar and microwave radiometers of the Network for the Detection Atmospheric Composition Change (NDACC) were selected to carry out comparisons with time series of MIPAS O3 partial columns and to identify groups of stations and time periods with a uniform pattern of ozone differences, that were subsequently used for a vertically resolved statistical analysis. The results of the comparison are classified according to synoptic and regional systems and to altitude intervals, showing a generally good agreement within the comparison error bars in the upper and middle stratosphere. Significant differences emerge in the lower stratosphere and are only partly explained by the larger contributions of horizontal and vertical smoothing differences and of collocation errors to the total uncertainty. Further results obtained from a purely statistical analysis of the same data set from NDACC ground-based lidar stations, as well as from additional ozone soundings at middle latitudes and from NDACC ground-based FTIR measurements, confirm the validity of MIPAS O3 profiles down to the lower stratosphere, with evidence of larger discrepancies at the lowest altitudes. The validation against O3 VMR profiles using collocated observations performed by other satellite sensors (SAGE II, POAM III, ODIN-SMR, ACE-FTS, HALOE, GOME) and ECMWF assimilated ozone fields leads to consistent results, that are to a great extent compatible with those obtained from the comparison with ground-based measurements. Excellent agreement in the full vertical range of the comparison is shown with respect to collocated ozone data from stratospheric aircraft and balloon instruments, that was mostly obtained in very good spatial and temporal coincidence with MIPAS scans. This might suggest that the larger differences observed in the upper troposphere and lowermost stratosphere with respect to collocated ground-based and satellite O3 data are only partly due to a degradation of MIPAS data quality. They should be rather largely ascribed to the natural variability of these altitude regions and to other components of the comparison errors. By combining the results of this large number of validation data sets we derived a general assessment of MIPAS v4.61 and v4.62 ozone data quality. A clear indication of the validity of MIPAS O3 vertical profiles is obtained for most of the stratosphere, where the mean relative difference with the individual correlative data sets is always lower than ±10%. Furthermore, these differences always fall within the combined systematic error (from 1 hPa to 50 hPa) and the standard deviation is fully consistent with the random error of the comparison (from 1 hPa to ~30–40 hPa). A degradation in the quality of the agreement is generally observed in the lower stratosphere and upper troposphere, with biases up to 25% at 100 hPa and standard deviation of the global mean differences up to three times larger than the combined random error in the range 50–100 hPa. The larger differences observed at the bottom end of MIPAS retrieved profiles can be associated, as already noticed, to the effects of stronger atmospheric gradients in the UTLS that are perceived differently by the various measurement techniques. However, further components that may degrade the results of the comparison at lower altitudes can be identified as potentially including cloud contamination, which is likely not to have been fully filtered using the current settings of the MIPAS cloud detection algorithm, and in the linear approximation of the forward model that was used for the a priori estimate of systematic error components. The latter, when affecting systematic contributions with a random variability over the spatial and temporal scales of global averages, might result in an underestimation of the random error of the comparison and add up to other error sources, such as the possible underestimates of the p and T error propagation based on the assumption of a 1 K and 2% uncertainties, respectively, on MIPAS temperature and pressure retrievals. At pressure lower than 1 hPa, only a small fraction of the selected validation data set provides correlative ozone data of adequate quality and it is difficult to derive quantitative conclusions about the performance of MIPAS O3 retrieval for the topmost layers.

Published
2007
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15. Towards the development of a fossil bone geochemical standard: An inter-laboratory study

Author

J. Breuer, H. Yuan, I. Roduhskin, T. Jong, Clive N. Trueman, J. Le Huray, Simone Pourtales, Olivier Bruguier, Dorrit E. Jacob, James A. Milton, George D. Kamenov, Yehan Liu, Analía L. Soldati, Martin R. Palmer, Valérie Chavagnac, Darryl R H Green, Géosciences Montpellier, and Université des Antilles et de la Guyane (UAG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Biogenic phosphate, Chemical composition, Mineralogy, chemistry.chemical_element, Fossil bone, Fossil bone/tooth, 010502 geochemistry & geophysics, 01 natural sciences, Biochemistry, Bone and Bones, Mass Spectrometry, Analytical Chemistry, Matrix (chemical analysis), [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Apatites, Environmental Chemistry, Animals, High field strength, Inter-laboratory, Spectroscopy, 0105 earth and related environmental sciences, Strontium, Chemistry, Rare-earth element, Fossils, Lasers, 010401 analytical chemistry, Trace element, Reproducibility of Results, Reference Standards, Organophosphates, 0104 chemical sciences, Trace Elements, Metals, Rare Earth, Reference material
Abstract

Ten international laboratories participated in an inter-laboratory comparison of a fossil bone composite with the objective of producing a matrix and structure-matched reference material for studies of the bio-mineralization of ancient fossil bone. We report the major and trace element compositions of the fossil bone composite, using in-situ method as well as various wet chemical digestion techniques. For major element concentrations, the intra-laboratory analytical precision (%RSDr) ranges from 7 to 18%, with higher percentages for Ti and K. The %RSDr are smaller than the inter-laboratory analytical precision (%RSDR; 100% was found for the high field strength elements (Hf, Th, Zr, Nb). The rare earth element (REE) concentrations, which vary over 3 orders of magnitude, have %RSDr and %RSDR values at 8-15% and 20-32%, respectively. However, the REE patterns (which are very important for paleo-environmental, taphonomic and paleo-oceanographic analyses) are much more consistent. These data suggest that the complex and unpredictable nature of the mineralogical and chemical composition of fossil bone makes it difficult to set-up and calibrate analytical instruments using conventional standards, and may result in non-spectral matrix effects. We propose an analytical protocol that can be employed in future inter-laboratory studies to produce a certified fossil bone geochemical standard. (C) 2007 Elsevier B.V. All rights reserved.

Published
2007
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16. Effects of vegetation patterns on yields of the surface and subsurface waters in the Heishui Alpine Valley in west China

Author

Z. Deng, Yehan Liu, Y. Zhi, N. Fan, Hong Yang, C. Zhou, S. Liu, S. An, Z. Wang, and EGU, Publication

Subjects
Hydrology, geography, geography.geographical_feature_category, [SDU.OCEAN] Sciences of the Universe [physics]/Ocean, Atmosphere, ved/biology, Stable isotope ratio, ved/biology.organism_classification_rank.species, Soil science, Vegetation, Effects of high altitude on humans, Shrub, [SDU.ENVI] Sciences of the Universe [physics]/Continental interfaces, environment, Yield (wine), Tributary, [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, Environmental science, Subsurface flow, Groundwater
Abstract

The relationships between different vegetation types and water yields were investigated in the Heishui Valley of the upper Yangtze River in western China. Contributions of groundwater and the water from surface and subsurface in different tributaries were, respectively, computed based on the stable isotope data, while the percentages of different vegetation covers were achieved by remote sensing in landscape scale. Based on the relationships between different vegetation types and water yields in seven watersheds, we found that reduction in the total vegetation, forest and subalpine coniferous forest covers could cause increasing in surface and subsurface water yields, while the water yield increased with the alpine shrub and meadow cover increasing, respectively. All the relationships were displayed as the low altitude and high altitude patterns, which were caused by the different vegetation characteristics and topography. We also found effects of the total vegetation cover played the most important role on water yield at large scale while the coniferous forest cover would affect the water yield at relatively small scale.

Published
2006
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17. Search for second-generation scalar leptoquarks inpp¯collisions ats=1.96 TeV

Author

M. Garcia Sciveres, P. F. Loverre, Peter Wagner, M. E. Convery, Tara Shears, M. M. Deninno, J.-F. Arguin, S. Baroiant, J. Miles, S. Lami, J. D. Lewis, Robin Erbacher, W-M. Yao, E. James, A. Hamilton, Jane Nachtman, A. Attal, R. McNulty, M. Hare, M. D. Shapiro, Allan G Clark, Roger Moore, M. H. Kirby, D. O. Litvintsev, Sooran Kim, Alberto Annovi, P. Movilla Fernandez, A. Connolly, D. Ryan, J. P. Chou, Y. Takeuchi, Petra Merkel, V. Khotilovich, P. H. Chu, K. T. Pitts, R. E. Hughes, A. Varganov, M. Loreti, S.S. Yu, S. Waschke, O. Saltó, Rainer Wallny, D. Waters, Rong-Shyang Lu, Luca Scodellaro, K. L. Byrum, A. Sedov, Koji Sato, V. Tiwari, Anna Zanetti, D. De Pedis, J. E. Kim, Petar Maksimovic, Joe Incandela, A. Napier, F. Azfar, A. Pronko, Arie Bodek, Y. Yamashita, S. Menzemer, S. Nahn, Manfred Paulini, Manuela Campanelli, G. Busetto, Brian L Winer, R. G. Wagner, J. C. Yun, Saverio D'Auria, I. Shreyber, A. Holloway, Helen Hayward, A. Dominguez, A. Abulencia, G. Flanagan, Yongsun Kim, F. Margaroli, Mauro Dell'Orso, J. Conway, M. Stanitzki, C. Haber, O. Norniella, L. Demortier, S. Dube, S. Miscetti, P. Mack, Y. C. Chen, S. Donati, Kenichi Hatakeyama, L. Santi, Giorgio Chiarelli, R. Mumford, M. Hennecke, K. Terashi, A. T. Laasanen, J. Spalding, J. R. Smith, K. Bloom, G. Pope, Frank Chlebana, Sinead Farrington, X. Portell, Z. Wan, Stefano Belforte, M. Ciljak, Masaaki Tanaka, B. Mohr, M. Schmitt, M. J. Wang, T. Miao, L. Ristori, D. Chokheli, Aldo Penzo, C. S. Hill, Nuno Leonardo, B. T. Huffman, Y. Gotra, Fumihiko Ukegawa, Sandra Leone, W. C. Wester, T. L. Watts, A. Rakitin, H. Matsunaga, K. Kondo, Dean Hidas, A. Sidoti, Peter McIntyre, B. Brau, C. Paus, M. Franklin, B. Jayatilaka, B. F. L. Ward, Jay Hauser, L. Zanello, Amitabh Lath, A. Sill, Alessandro Cerri, Marc Weber, Daniel Jeans, K. Gibson, Xin Wu, J. Sjolin, S. Levy, Alberto Belloni, F. Zetti, C. Mesropian, P. Sinervo, A. E. Kreymer, M. J. Kim, A. Loginov, A. B. Wicklund, J. C. Freeman, A. Kovalev, E. Gerchtein, Ivan-Kresimir Furic, Y. D. Oh, Massimo Casarsa, Henrik Jeldtoft Jensen, V. V. Glagolev, J. Proudfoot, Laurent Vacavant, C. Pagliarone, E. Palencia, Paola Giannetti, B. A. Barnett, Giorgio Apollinari, T. Walter, T. R. Junk, Andrew Ivanov, S. Tkaczyk, David Stuart, R. G. Feild, J. S. Suh, K. Rinnert, A. Rahaman, Teruki Kamon, E. E. Schmidt, Markus Klute, R. Kephart, N. Moggi, D. W. Jang, F. Ptohos, W. J. Robertson, W. K. Sakumoto, A. Ruiz, C. Wolfe, J. Lee, D. Stentz, D. Dagenhart, N. S. Lockyer, E. Thomson, Daniela Bortoletto, B. Parks, I. Zaw, S. H. Chuang, J. W. Chapman, D. J. Kong, T. Maruyama, F. Ratnikov, C. Neu, Vladimir Rekovic, M. Giunta, G. Velev, V. Boisvert, Louis Lyons, S. Zucchelli, R. E. Blair, P. E. Karchin, A. Miyamoto, N. Goldschmidt, Virgil E Barnes, Craig Blocker, G. P. Yeh, Tony Liss, Beate Heinemann, D. Amidei, Joel Goldstein, Tiehui Liu, V. Necula, S. M. Wynne, Roberto Rossin, I. Nakano, U. K. Yang, G. Punzi, Kaori Maeshima, F. Rimondi, V. Papadimitriou, W. H. Chung, T. Nigmanov, Yehan Liu, Elliot Lipeles, G. De Lentdecker, Chris Hays, C. Grosso-Pilcher, Carmen Navarro Sanchez, H. Kobayashi, E. Lytken, J. N. Bellinger, J. Ehlers, A. Menzione, Jian Zhou, M. Donega, A. Artikov, Teresa Rodrigo, T. J. Phillips, H. Bachacou, Sam Harper, S. Seidel, F. Happacher, C. Mills, Dario Bisello, A. Bhatti, A. T. Goshaw, S. Demers, B. Reisert, R. Culbertson, S. Torre, P. Lukens, K. Giolo, S. Behari, Daijin Kim, J. Boudreau, P. Wilson, M. Goncharov, Joe Kroll, S. Tourneur, Andrew Beretvas, C. Dionisi, C. Plager, M. Griffiths, N. Pounder, Carsten Rott, L. Sexton-Kennedy, Matteo Cavalli-Sforza, P. McNamara, Igor Sfiligoi, M. Campbell, I. Vollrath, R. Tsuchiya, Salvatore Rappoccio, C.-S. Lin, T. Wright, R. J. Miller, G. Piacentino, J. Lys, F. Prakoshyn, D. Sherman, R. Roser, Ivan Vila, D. Naumov, Paolo Azzurri, M. von der Mey, G. Pauletta, P. Squillacioti, Kazuhiko Hara, P. DiTuro, M. Feindt, S. H. Chang, P. Schlabach, A. Cruz, J. Efron, E. Ben Haim, D. Lucchesi, Bernd Stelzer, N. Giokaris, Stefano Giagu, M. Coca, David Saltzberg, Monica D'Onofrio, T. Akimoto, A. Gresele, S. Tsuno, M. Tecchio, Giovanni Bellettini, S. E. Kuhlmann, J. S. Miller, Kevin Burkett, R. Handler, Y. S. Chung, N. Krumnack, A. Mukherjee, V. Rusu, N. Van Remortel, L. R. Flores-Castillo, M. Rossi, F. Spinella, Jochen Jens Heinrich, W. T. Fedorko, M. Martinez, Ramon Miquel, A. S. Thompson, Antonio Boveia, X. Zhang, G. P. Di Giovanni, Inhee Cho, S. DaRonco, G. Giurgiu, D. Usynin, U. Kerzel, J. Beringer, J. P. Fernandez, Nicola Bacchetta, D. MacQueen, H. Gerberich, R. Tafirout, S. Grinstein, R. F. Harr, Andrea Bocci, G. Chlachidze, K. Li, N. Miladinovic, Matthew Herndon, T. Vickey, K. Ebina, K. S. McFarland, Pierre Savard, A. J. Slaughter, Alexei Safonov, A. L. Scott, S. Tether, N. Turini, K. Takikawa, J. M. Heuser, Y. Ishizawa, S. De Cecco, Chen Yang, P. F. Derwent, Tommaso Dorigo, M. Tönnesmann, R. St. Denis, Ilya Kravchenko, C. Dörr, Maria Agnese Ciocci, G. W. Foster, James Russ, Kohei Yorita, D. Glenzinski, T. Unverhau, A. Scribano, A. Papikonomou, A. Staveris-Polykalas, S. Worm, S. Rolli, Benjamin Kilminster, C. P. Marino, M. Bishai, J. Mülmenstädt, M. Lancaster, K. K. Joo, A. Heijboer, R. Vilar, Barry Blumenfeld, M. Aoki, A. Skiba, F. Bedeschi, E. Rogers, A. Soha, Kevin Lannon, B. Knuteson, D. Smirnov, G. Cortiana, P. Mazzanti, J. Yoh, Mark Neubauer, Subir Sarkar, R. Orava, Guenakh Mitselmakher, Gervasio Gomez, S. R. Hou, S. Errede, P. J. Bussey, S. Cabrera, S. Uozumi, J. E. Garcia, M. J. Shochet, D. E. Pellett, R. Madrak, V. Martin, A. J. Martin, E. Vataga, William Trischuk, Stephan Lammel, Lucio Cerrito, T. Scheidle, E. Brubaker, S. Pashapour, Guillelmo Gomez-Ceballos, M. Soderberg, D. Ambrose, T. Suzuki, Y. Kemp, H. S. Budd, J. Huston, J. Kang, L. Pondrom, E. Wicklund, H. Saarikko, S. Kwang, A. Gajjar, K. Ikado, A. Barbaro-Galtieri, T. Ogawa, F. Semeria, Andrey Korytov, S. Bourov, R. Marginean, J. Kraus, G. Lungu, H. H. Williams, Jonas Rademacker, G. Latino, Y. Kusakabe, O. Stelzer-Chilton, R. Mazini, K. Copic, Avraham Yagil, S. Richter, Michal Kreps, H. C. Fang, Frank Würthwein, E. J. Jeon, A. Canepa, Eva Halkiadakis, S. R. Hahn, A. Vaiciulis, A. Sukhanov, Y. Shon, M. Mulhearn, M. Cordelli, J. Deng, M. E. Mattson, Sofia Vallecorsa, Fabrizio Scuri, L. E. Kirsch, S. W. Lee, S. Budd, S. H. Kim, I. Fedorko, S. Carron, J. Antos, Ricardo Eusebi, Tetsuo Arisawa, R. D. Field, R. Vidal, R. Oldeman, Konstanty Sumorok, Aurore Savoy-Navarro, G. Manca, Javier Cuevas, G. Introzzi, B. D. Cooper, Duncan Carlsmith, K. Chung, Julien Donini, Koji Yamamoto, MarioPaolo Giordani, R. Takashima, P. K. Teng, Ulysses Grundler, C. M. Ginsburg, J. Budagov, T. Tomura, M. Jones, Thomas LeCompte, K. Goulianos, A. Taffard, P. De Barbaro, W. Ashmanskas, A. Messina, R. L. Lander, Julia Thom, K. Osterberg, J. Piedra, P. F. Shepard, S. H. Oh, G. Salamanna, K. Kordas, B. R. Ko, Keunchang Cho, O. Poukhov, Y. Seiya, Reisaburo Tanaka, Sheng Wang, M. Karagoz-Unel, P. B. Renton, P. Dong, R. Lysak, J. Patrick, Paul Lujan, M. P. Schmidt, Th. Müller, R. Carosi, V. Sorin, Maxwell Chertok, Min Soo Kim, Alexander Paramonov, M. Lindgren, A. Bolshov, Thomas Andrew Schwarz, Jay Dittmann, D. Cauz, P. Azzi-Bacchetta, P. Catastini, C. Bromberg, A. Deisher, Alan Garfinkel, Darin Acosta, Tomoko Yoshida, Kristian Allan Hahn, K. Sliwa, S. Klimenko, D. Cyr, Y. Kato, D. Hirschbuehl, Tracey Berry, D. McGivern, Riccardo Paoletti, J. Strologas, Michele Gallinaro, A. Gibson, Peter Wittich, M. Rescigno, A. Foland, A. Hocker, J. Yamaoka, Mark Kruse, Alison Lister, Paul Tipton, J. Galyardt, R. L. Wagner, S. Forrester, D. Toback, M. Gold, M. Shimojima, Intae Yu, J. Nielsen, C. S. Lin, Vyacheslav Krutelyov, P. Murat, Jahred Adelman, L. Nodulman, Y. Fujii, M. Martin, G. Bauer, M. J. Morello, F. D. Snider, S. Wolbers, D. W. Gerdes, M. Iori, T. Affolder, S. Amerio, S. Somalwar, C. I. Ciobanu, Gino Bolla, D. Tonelli, D. Torretta, S. Tokar, Andrew Mehta, Jacobo Konigsberg, R. Snihur, Daniel Whiteson, B. Y. Han, R. Lefèvre, H. Sun, A. N. Sisakyan, W. Badgett, K. Tollefson, O. González, A. V. Kotwal, S. C. Hsu, Andreas Warburton, Hanbit Kim, Robert M Harris, G. Veramendi, Andrea Castro, C. Lecci, Igor Volobouev, S. Lai, M. Milnik, T. Okusawa, A. Semenov, D. Clark, S. Sabik, I. Lazzizzera, A. Anastassov, F. Canelli, B. Iyutin, M. Binkley, M. G. Albrow, K. Anikeev, Aidan Robson, D. P. Benjamin, D. Errede, J. Pursley, Wolfgang Wagner, V. Bartsch, J. Guimaraes Da Costa, I. V. Gorelov, M. A. Houlden, B. Whitehouse, Viktor Veszpremi, and S. Y. Jun

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, Missing energy, 010308 nuclear & particles physics, Branching fraction, High Energy Physics::Phenomenology, Tevatron, 01 natural sciences, Nuclear physics, Pair production, 0103 physical sciences, High Energy Physics::Experiment, Leptoquark, Production (computer science), 010306 general physics, Lepton
Abstract

Results on a search for pair production of second generation scalar leptoquark in p{bar p} collisions at {radical}s=1.96 TeV are reported. The data analyzed were collected by the CDF detector during the 2002-2003 Tevatron Run II and correspond to an integrated luminosity of 198 pb{sup -1}. Leptoquarks (LQ) are sought through their decay into (charged) leptons and quarks, with final state signatures represented by two muons and jets and one muon, large transverse missing energy and jets. We observe no evidence for LQ production and derive 95% C.L. upper limits on the LQ production cross sections as well as lower limits on their mass as a function of {beta}, where {beta} is the branching fraction for LQ {yields} {mu}q.

Published
2006
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18. Measurement of Nonrandom Event-by-Event Fluctuations of Average Transverse Momentum insNN=200 GeVAu+Auandp+pCollisions

Author

Steven Kelly, Y. I. Makdisi, I. Ravinovich, B. D. Fox, T. Peitzmann, Saskia Mioduszewski, S. Bathe, F. Plasil, Jason Newby, J. Murata, M. J. Tannenbaum, H. Tsuruoka, H. W. Van Hecke, S. S. Ryu, J. E. Frantz, Norio Saito, Herve Borel, Kensuke Homma, R. A. Soltz, Yehan Liu, S. Afanasiev, A. Glenn, M. Issah, A. Taketani, E. Melnikov, A. Ster, N. Kamihara, V. V. Ikonnikov, Yves Roland Schutz, Martin Purschke, S. Zhou, Shih-Chang Lee, F. Matathias, S. Chernichenko, H. Lim, Masamichi Ishihara, T. E. Miller, E. Vznuzdaev, K. S. Sim, Y. J. Kwon, D. Bucher, B. Bassalleck, F. Mühlbacher, M. Grosse Perdekamp, R. Santo, A. Enokizono, L. Ewell, Alexander Milov, Minghui Liu, D. Pal, J. Chiba, V. Bumazhnov, T. Shiina, A. Drees, J. B. Choi, M. Sakai, E. J. Desmond, D. Kotchetkov, S. Bhagavatula, L. Sanfratello, S. Kametani, S. Borenstein, M. Heffner, R. Azmoun, E. M. Takagui, F. Messer, R. S. Towell, V. Babintsev, M. Hibino, Kenneth Francis Read, G. C. Mishra, D. Mukhopadhyay, J. Park, Takao Sakaguchi, Y. Cobigo, Wei Xie, M. A. Volkov, T. Ichihara, Z. Fraenkel, O. Drapier, J. T. Mitchell, David Olle Rickard Silvermyr, C. Klein-Boesing, J. H. Kang, A. Deshpande, A. D. Frawley, C. A. Ogilvie, K. Imai, E. P. Hartouni, Vladislav Manko, J. S. Haggerty, T. K. Hemmick, R. K. Choudhury, V.A. Onuchin, A. Romana, S. Sawada, J. D. Tepe, G. Gogiberidze, D. P. Morrison, M. Chiu, Ajit Kumar Mohanty, T. A. Shibata, S. Belikov, K. S. Joo, Yasuo Miake, M. D. Marx, R. Amirikas, W. C. Chang, P. Chand, A. Franz, K. Kiyoyama, N. Grau, S. H. Aronson, S. S. Kapoor, V. S. Pantuev, I. E. Yushmanov, L. Kochenda, T. Chujo, C. Y. Chi, V. E. Semenov, Eun-Hee Kim, X. Camard, P. Tarján, Y. Kuroki, B. K. Nandi, C. L. Woody, W. Holzmann, Margaret Harvey, Alexei Khanzadeev, H. J. Kim, W. Y. Jang, B. Khachaturov, A. Parmar, N. Bruner, E. Stenlund, S. Butsyk, Christine Angela Aidala, H. Kobayashi, T. Matsumoto, D. Isenhower, Junji Tojo, A. G. Litvinenko, L. Aphecetche, Vladimir Samsonov, I. Otterlund, German Martinez, Y. Yang, Agneta Oskarsson, S. P. Sorensen, S. F. Pate, P. W. Stankus, Jen-Chieh Peng, C. P. Singh, D. W. Kim, G. R. Young, B. M. Johnson, Y. Berdnikov, Y. Akiba, K. Okada, S. S. Adler, Joakim Nystrand, X. R. Wang, G. S. Kyle, James Alexander, A. Isupov, S. P. Stoll, S. Nagamiya, Kazuhiro Tanaka, H. En'yo, T. C. Awes, P. Constantin, M. J. Leitch, Klaus Johannes Reygers, Y. Watanabe, O. Dietzsch, Y. Jeong, R. Averbeck, Byung-Sik Hong, Kyoichiro Ozawa, L. Villatte, Jun Kikuchi, J. L. Nagle, G. Bunce, Dong Jo Kim, A. Bazilevsky, Peter M. Nilsson, Philippe Rosnet, Brian Cole, H. Delagrange, T. Kohama, D. Jouan, J. S. Chai, David D'Enterria, Jan Rak, W. Guryn, Alexandre Lebedev, A. Kozlov, D. M. Lee, V. Papavassiliou, Dipanwita Dutta, R. Lacey, P. L. McGaughey, Senta Greene, R. P. Pisani, R. Granier de Cassagnac, M. Nara, I. Tserruya, R. Seto, A. Soldatov, Yu. Efremenko, M. Kopytine, J. M. Burward-Hoy, Nikolay Tyurin, V. Singh, G. B. Kim, D. Koehler, C. L. Silva, J. G. Lajoie, Hideki Hamagaki, G. David, C. H. Kuberg, T. Hachiya, Julia Velkovska, Hirohiko Sato, S. K. Tuli, V. P. Ladygin, S. Garpman, Susumu Sato, M. Muniruzzaman, H. A. Gustafsson, E. O'Brien, P. J. Kroon, K. Tanida, V. I. Kochetkov, R. E. Mischke, C. Zhang, M. Rosati, Dong-Hun Kim, M. Velkovsky, Y. Tanaka, T. K. Shea, I. J. Choi, Alberto Baldisseri, K. N. Barish, Viktor Riabov, I. V. Sourikova, H. Torii, M. Ono, F. Staley, Charles Maguire, S. Leckey, A. A. Vinogradov, Henrik Tydesjö, M. L. Brooks, R. du Rietz, Josh Moss, M. Tamai, X. He, E. Kistenev, V. Peresedov, Jiangyong Jia, Y. Goto, J. G. Boissevain, H. Masui, W. A. Zajc, K. Katou, V. Baublis, A. Denisov, V. Cianciolo, A. Kiyomichi, C. Pinkenburg, A. G. Hansen, Shingo Sakai, T. L. Thomas, Sergey Fokin, M. Stepanov, G. Roche, Ryugo S. Hayano, J. Gosset, Y. Riabov, J. P. Sullivan, Kenta Shigaki, A. S. Nyanin, A. Hoover, S. Yokkaichi, J. M. Heuser, S. Batsouli, A. P.T. Palounek, M. Gonin, K. Kurita, M. Sivertz, Hiroaki Ohnishi, J. Milan, H. Buesching, Xingguo Li, D. E. Fields, B. V. Jacak, A. K. Purwar, N. N. Ajitanand, Takahiro Nakamura, M. E. Sadler, A. Durum, D. S. Brown, S. Y. Fung, John Hill, K. Oyama, Toru Sugitate, François Fleuret, S. N. White, W. E. Sondheim, Osamu Jinnouchi, F. K. Wohn, T. K. Ghosh, Matthew G. Reuter, I. D. Ojha, Alexander Malakhov, L. S. Zolin, S. Esumi, P. D. Barnes, A. Yanovich, K. El Chenawi, M. R. Shaw, S. C. Johnson, Y. J. Mao, and M. J. Kweon

Subjects
Physics, Momentum (technical analysis), Range (particle radiation), 010308 nuclear & particles physics, General Physics and Astronomy, Collision, 01 natural sciences, Nuclear physics, Particle emission, 0103 physical sciences, Transverse momentum, Particle, Atomic physics, Nuclear Experiment, 010306 general physics, Relativistic Heavy Ion Collider, Event (particle physics)
Abstract

Event-by-event fluctuations of the average transverse momentum of produced particles near midrapidity have been measured by the PHENIX Collaboration in square root of (sNN)=200 GeV Au+Au, and p+p collisions at the Relativistic Heavy Ion Collider. The fluctuations are observed to be in excess of the expectation for statistically independent particle emission for all centralities. The excess fluctuations exhibit a dependence on both the centrality of the collision and on the pT range over which the average is calculated. Both the centrality and pT dependence can be well reproduced by a simulation of random particle production with the addition of contributions from hard-scattering processes.

Published
2004
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19. Experimental Study of Mechanical Hysteresis of NiTi During Ferroelastic and Superelastic Deformation

Author

Denis Favier, Laurent Orgéas, and Yehan Liu

Subjects
010302 applied physics, Materials science, Ferroelasticity, Metallurgy, General Physics and Astronomy, 02 engineering and technology, Shape-memory alloy, 021001 nanoscience & nanotechnology, 01 natural sciences, Hysteresis, Nickel titanium, Martensite, Diffusionless transformation, [PHYS.HIST]Physics [physics]/Physics archives, 0103 physical sciences, Pseudoelasticity, Deformation (engineering), Composite material, 0210 nano-technology
Abstract

Shape memory alloys are known to exhibit a range of novel thermomechanical behaviour associated with the unique thermoelastic martensitic transformation. Such behaviour includes the superelasticity associated with stress-induced martensitic transformation at relatively high temperatures and the ferroelasticity associated with a martensite reorientation process at low temperatures. Both the stress-induced martensitic transformation and the martensite reorientation are energy-dissipative processes, i.e., hysteretic between the forward and reverse processes. This work was aimed at studying the hysteretic behaviour of the ferroelasticity and superelasticity observed in a polycrystalline NiTi alloy by carrying out simple shear deformation tests through both major and subloop cycles. It was found that subloops are always closed and enclosed inside the major loop and that the stress hysteresis of a subloop is only dependent on the strain amplitude of the subloop, regardless of the position of the subloop inside the major loop.

Published
1997
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20. PYROLYSIS-LASER PHOTOACOUSTIC SPECTRA (PLPAS) OF POLYMERS

Author

Yehan Liu, Ding Sheng Wang, C. Chen, and W. Wang

Subjects
chemistry.chemical_classification, Materials science, Co2 laser, Polymer composition, General Engineering, Photoacoustic imaging in biomedicine, Polymer, Laser, Spectral line, law.invention, chemistry, Chemical engineering, Fingerprint, law, Pyrolysis
Abstract

A combination of polymer pyrolysis and CO2 laser photoacoustic detection is proposed. Characteristic fingerprint patterns thus obtained give information on polymer composition.

Published
1983
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