208 results on '"Ron Folman"'
Search Results
2. Constructing nano-object quantum superpositions with a Stern-Gerlach interferometer
- Author
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Ryan J. Marshman, Anupam Mazumdar, Ron Folman, and Sougato Bose
- Subjects
Physics ,QC1-999 - Abstract
Probing quantum mechanics and quantum aspects of general relativity, along with the sensing and constraining of classical gravity, can all be enabled by unprecedented spatial sizes of superpositions of massive objects. In this paper, we show that there is a feasible setup sourced by realizable magnetic field gradients O(10–100)T m^{−1} to construct a large spatial superposition of O(10^{−4}–10^{−8})m for O(10^{−17}–10^{−14})kg masses within a time of up to 0.1–10 seconds. The scale of superpositions is unrestricted as long as quantum coherence can be maintained for a required amount of time.
- Published
- 2022
- Full Text
- View/download PDF
3. Anomalous periodicity in superpositions of localized periodic patterns
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Omer Amit, Or Dobkowski, Zhifan Zhou, Yair Margalit, Yonathan Japha, Samuel Moukouri, Yigal Meir, Baruch Horovitz, and Ron Folman
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atom interferometry ,Moiré ,quantum mechanics ,wave mechanics ,interference ,Science ,Physics ,QC1-999 - Abstract
Interference between overlapping periodic patterns gives rise to important phenomena, such as Moiré fringes, appearing when the patterns have different periods or orientations. Here we present a novel phenomenon, applicable to both the classical and quantum regimes, where two one-dimensional localized periodic patterns with the same period interfere to create fringes with anomalous periodicity. We analyze the effect theoretically and demonstrate it with atomic matter waves. When a central parameter of the system is scanned continuously, we observe a discontinuous but piecewise-rigid periodicity of the resulting fringes. We show that this is a universal phenomenon that emerges from a superposition of two spatially shifted localized periodic patterns of any source or nature when they interfere with a global phase difference. The rigidity of the spectrum becomes even more robust for a coherent superposition of non-overlapping wavepackets, although the conventional interferometric visibility drops to zero. The effect is expected to appear in space and time, as well as in the momentum distribution of quantum particles.
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- 2022
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4. Using a quantum work meter to test non-equilibrium fluctuation theorems
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Federico Cerisola, Yair Margalit, Shimon Machluf, Augusto J. Roncaglia, Juan Pablo Paz, and Ron Folman
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Science - Abstract
Defining and measuring work and heat are non-trivial tasks in the quantum regime. Here, the authors design a scheme to directly sample from the work probability distribution, and use it to verify the validity of the quantum version of the Jarzynksi identity using cold atoms on an atomic chip.
- Published
- 2017
- Full Text
- View/download PDF
5. Analysis of a high-stability Stern–Gerlach spatial fringe interferometer
- Author
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Yair Margalit, Zhifan Zhou, Shimon Machluf, Yonathan Japha, Samuel Moukouri, and Ron Folman
- Subjects
matter-wave interferometry ,Stern–Gerlach effect ,atom chips ,Science ,Physics ,QC1-999 - Abstract
The discovery of the Stern–Gerlach (SG) effect almost a century ago was followed by suggestions to use the effect as a basis for matter-wave interferometry. However, the coherence of splitting particles with spin by a magnetic gradient to a distance exceeding the position uncertainty in each of the arms was not demonstrated until recently, where spatial interference fringes were observed in a proof-of-principle experiment. Here we present and analyze the performance of an improved high-stability SG spatial fringe interferometer based on two spatially separate wave packets with a maximal distance that is more than an order of magnitude larger than their minimal widths. The improved performance is enabled by accurate magnetic field gradient pulses, originating from a novel atom chip configuration, which ensures high stability of the interferometer operation. We analyze the achieved stability using several models, discuss sources of noise, and detail interferometer optimization procedures. We also present a simple analytical phase-space description of the interferometer sequence that demonstrates quantitatively the complete separation of the superposed wave packets ^2 .
- Published
- 2019
- Full Text
- View/download PDF
6. Stern–Gerlach splitting of low-energy ion beams
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Carsten Henkel, Georg Jacob, Felix Stopp, Ferdinand Schmidt-Kaler, Mark Keil, Yonathan Japha, and Ron Folman
- Subjects
spin-dependent forces ,Stern–Gerlach effect ,ion optics ,beam splitter ,magnetic microstructures ,Science ,Physics ,QC1-999 - Abstract
We present a feasibility study with several magnetic field configurations for creating spin-dependent forces that can split a low-energy ion beam by the Stern–Gerlach (SG) effect. To the best of our knowledge, coherent spin-splittings of charged particles have yet to be realised. Our proposal is based on ion source parameters taken from a recent experiment that demonstrated single-ion implantation from a high-brightness ion source combined with a radio-frequency Paul trap. The inhomogeneous magnetic fields can be created by permanently magnetised microstructures or from current-carrying wires with sizes in the micron range, such as those recently used in a successful implementation of the SG effect with neutral atoms. All relevant forces (Lorentz force and image charges) are taken into account, and measurable splittings are found by analytical and numerical calculations.
- Published
- 2019
- Full Text
- View/download PDF
7. Suppression and enhancement of decoherence in an atomic Josephson junction
- Author
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Yonathan Japha, Shuyu Zhou, Mark Keil, Ron Folman, Carsten Henkel, and Amichay Vardi
- Subjects
atomtronics ,coherence ,ultracold atoms ,Bose–Einstein condensate ,Bose–Hubbard model ,tunneling ,Science ,Physics ,QC1-999 - Abstract
We investigate the role of interatomic interactions when a Bose gas, in a double-well potential with a finite tunneling probability (a ‘Bose–Josephson junction’), is exposed to external noise. We examine the rate of decoherence of a system initially in its ground state with equal probability amplitudes in both sites. The noise may induce two kinds of effects: firstly, random shifts in the relative phase or number difference between the two wells and secondly, loss of atoms from the trap. The effects of induced phase fluctuations are mitigated by atom–atom interactions and tunneling, such that the dephasing rate may be suppressed by half its single-atom value. Random fluctuations may also be induced in the population difference between the wells, in which case atom–atom interactions considerably enhance the decoherence rate. A similar scenario is predicted for the case of atom loss, even if the loss rates from the two sites are equal. We find that if the initial state is number-squeezed due to interactions, then the loss process induces population fluctuations that reduce the coherence across the junction. We examine the parameters relevant for these effects in a typical atom chip device, using a simple model of the trapping potential, experimental data, and the theory of magnetic field fluctuations near metallic conductors. These results provide a framework for mapping the dynamical range of barriers engineered for specific applications and set the stage for more complex atom circuits (‘atomtronics’).
- Published
- 2016
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8. Realization of a complete Stern-Gerlach interferometer: towards a test of quantum gravity
- Author
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Ron Folman
- Published
- 2023
- Full Text
- View/download PDF
9. Stern-Gerlach Interferometry with the Atom Chip
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Omer Amit, Yigal Meir, Shimon Machluf, Yonathan Japha, Daniel Rohrlich, Ron Folman, Yaniv Bar-Haim, Zina Binstock, Or Dobkowski, David Groswasser, Zhifan Zhou, Samuel Moukouri, Yair Margalit, Menachem Givon, and Mark Keil
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Physics ,Stern–Gerlach experiment ,Interference (wave propagation) ,Chip ,01 natural sciences ,010305 fluids & plasmas ,Computational physics ,Magnetic field ,Metrology ,Interferometry ,Quantum process ,0103 physical sciences ,Atomic physics ,010306 general physics ,Realization (systems) - Abstract
In this invited review in honor of 100 years since the Stern-Gerlach (SG) experiments, we describe a decade of SG interferometry on the atom chip. The SG effect has been a paradigm of quantum mechanics throughout the last century, but there has been surprisingly little evidence that the original scheme, with freely propagating atoms exposed to gradients from macroscopic magnets, is a fully coherent quantum process. Specifically, no full-loop SG interferometer (SGI) has been realized with the scheme as envisioned decades ago. Furthermore, several theoretical studies have explained why it is a formidable challenge. Here we provide a review of our SG experiments over the last decade. We describe several novel configurations such as that giving rise to the first SG spatial interference fringes, and the first full-loop SGI realization. These devices are based on highly accurate magnetic fields, originating from an atom chip, that ensure coherent operation within strict constraints described by previous theoretical analyses. Achieving this high level of control over magnetic gradients is expected to facilitate technological applications such as probing of surfaces and currents, as well as metrology. Fundamental applications include the probing of the foundations of quantum theory, gravity, and the interface of quantum mechanics and gravity. We end with an outlook describing possible future experiments.
- Published
- 2021
- Full Text
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10. Constructing Nano-Object Quantum Superpositions with a Stern-Gerlach Interferometer
- Author
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Ryan J. Marshman, Anupam Mazumdar, Ron Folman, Sougato Bose, and Cosmic Frontier
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Quantum Physics ,FOS: Physical sciences ,General Relativity and Quantum Cosmology (gr-qc) ,Quantum Physics (quant-ph) ,General Relativity and Quantum Cosmology - Abstract
Probing quantum mechanics, quantum aspects of general relativity along with the sensing and the constraining of classical gravity can all be enabled by unprecedented spatial sizes of superpositions of massive objects. In this paper, we show that there is a feasible setup sourced by realizable magnetic field gradients ${\cal O}(10-100)$ Tm$^{-1}$ to construct a large spatial superposition of ${\cal O}(10^{-4}-10^{-8})$ m for masses ${\cal O}(10^{-16}-10^{-14})$ kg over a time period of up to $0.1-10$ seconds., Comment: 8 pages, 6 figures
- Published
- 2021
- Full Text
- View/download PDF
11. An experimental test of the geodesic rule proposition for the noncyclic geometric phase
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Samuel Moukouri, Zhifan Zhou, Yigal Meir, Ron Folman, and Yair Margalit
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Geodesic ,General relativity ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,01 natural sciences ,010309 optics ,Theoretical physics ,symbols.namesake ,Computer Science::Hardware Architecture ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,Physics::Atomic Physics ,010306 general physics ,Quantum ,Research Articles ,Physics ,Condensed Matter::Quantum Gases ,Multidisciplinary ,SciAdv r-articles ,Quantum technology ,Interferometry ,Geometric phase ,Bounded function ,symbols ,Hamiltonian (quantum mechanics) ,Research Article - Abstract
This paper describes geometric effects in the evolution of atoms through a double-slit type experiment on an atom chip., The geometric phase due to the evolution of the Hamiltonian is a central concept in quantum physics and may become advantageous for quantum technology. In noncyclic evolutions, a proposition relates the geometric phase to the area bounded by the phase-space trajectory and the shortest geodesic connecting its end points. The experimental demonstration of this geodesic rule proposition in different systems is of great interest, especially due to the potential use in quantum technology. Here, we report a previously unshown experimental confirmation of the geodesic rule for a noncyclic geometric phase by means of a spatial SU(2) matter-wave interferometer, demonstrating, with high precision, the predicted phase sign change and π jumps. We show the connection between our results and the Pancharatnam phase. Last, we point out that the geodesic rule may be applied to obtain the red shift in general relativity, enabling a new quantum tool to measure gravity.
- Published
- 2020
12. Stern-Gerlach splitting of low-energy ion beams
- Author
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Mark Keil, Georg Jacob, Ferdinand Schmidt-Kaler, Carsten Henkel, Felix Stopp, Ron Folman, and Yonathan Japha
- Subjects
Physics ,Quantum Physics ,Stern–Gerlach experiment ,Ion beam ,Atomic Physics (physics.atom-ph) ,Institut für Physik und Astronomie ,General Physics and Astronomy ,FOS: Physical sciences ,01 natural sciences ,Ion source ,Charged particle ,Physics - Atomic Physics ,010305 fluids & plasmas ,Magnetic field ,Ion ,symbols.namesake ,0103 physical sciences ,symbols ,ddc:530 ,Ion trap ,Atomic physics ,010306 general physics ,Quantum Physics (quant-ph) ,Lorentz force - Abstract
We present a feasibility study with several magnetic field configurations for creating spin-dependent forces that can split a low-energy ion beam by the Stern-Gerlach effect. To the best of our knowledge, coherent spin-splittings of charged particles have yet to be realised. Our proposal is based on ion source parameters taken from a recent experiment that demonstrated single-ion implantation from a high-brightness ion source combined with a radio-frequency Paul trap. The inhomogeneous magnetic fields can be created by permanently magnetised microstructures or from current-carrying wires with sizes in the micron range, such as those recently used in a successful implementation of the Stern-Gerlach effect with neutral atoms. All relevant forces (Lorentz force and image charges) are taken into account, and measurable splittings are found by analytical and numerical calculations., Comment: 22 pages, 6 figures, expanded discussion about Stern-Gerlach splitting of electrons
- Published
- 2019
- Full Text
- View/download PDF
13. T^3-Stern-Gerlach Matter-Wave Interferometer
- Author
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Yonathan Japha, Ron Folman, Yair Margalit, Wolfgang P. Schleich, Maxim A. Efremov, Omer Amit, Frank A. Narducci, Ernst M. Rasel, Zhifan Zhou, Matthias Zimmermann, and Or Dobkowski
- Subjects
Physics ,Quantum Physics ,Stern–Gerlach experiment ,business.industry ,Atomic Physics (physics.atom-ph) ,Phase (waves) ,General Physics and Astronomy ,FOS: Physical sciences ,01 natural sciences ,Physics - Atomic Physics ,Interferometry ,Optics ,0103 physical sciences ,Atom ,Astronomical interferometer ,Matter wave ,Cube ,010306 general physics ,business ,Quantum Physics (quant-ph) ,Realization (systems) - Abstract
We present a unique matter-wave interferometer whose phase scales with the cube of the time the atom spends in the interferometer. Our scheme is based on a full-loop Stern-Gerlach interferometer incorporating four magnetic field gradient pulses to create a state-dependent force. In contrast to typical atom interferometers which make use of laser light for the splitting and recombination of the wave packets, this realization uses no light and can therefore serve as a high-precision surface probe at very close distances., Comment: Phys. Rev. Lett., in print, https://journals.aps.org/prl/
- Published
- 2019
- Full Text
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14. Fifteen years of cold matter on the atom chip: promise, realizations, and prospects
- Author
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Yonathan Japha, Omer Amit, David Groswasser, Ron Folman, Mark Keil, and Shuyu Zhou
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Physics ,Condensed Matter::Quantum Gases ,Atomic Physics (physics.atom-ph) ,Condensed Matter::Other ,FOS: Physical sciences ,Context (language use) ,02 engineering and technology ,Original Articles ,Atom chip ,Bose-Einstein condensate ,ultracold atomic physics ,matter-wave quantum technology ,quantum optics ,atomtronics ,021001 nanoscience & nanotechnology ,Chip ,7. Clean energy ,01 natural sciences ,Engineering physics ,Atomic and Molecular Physics, and Optics ,Article ,Physics - Atomic Physics ,0103 physical sciences ,Atom ,Atomic physics ,010306 general physics ,0210 nano-technology ,Realization (systems) - Abstract
Here we review the field of atom chips in the context of Bose-Einstein Condensates (BEC) as well as cold matter in general. Twenty years after the first realization of the BEC and fifteen years after the realization of the atom chip, the latter has been found to enable extraordinary feats: from producing BECs at a rate of several per second, through the realization of matter-wave interferometry, and all the way to novel probing of surfaces and new forces. In addition, technological applications are also being intensively pursued. This review will describe these developments and more, including new ideas which have not yet been realized., Comment: 44 pages, 36 figures, 389 references, table of contents, list of abbreviations
- Published
- 2016
15. Wide-Field Imaging of Superconductor Vortices with Electron Spins in Diamond
- Author
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Lykourgos Bougas, A. Waxman, Dominik Rohner, Dmitry Budker, Lucas Thiel, David Groswasser, Michael Kieschnick, E. Rozenberg, Till Lenz, Patrick Maletinsky, Jan Meijer, Yechezkel Schlussel, Yaniv Bar-Haim, and Ron Folman
- Subjects
Magnetic domain ,Magnetism ,FOS: Physical sciences ,General Physics and Astronomy ,02 engineering and technology ,Electron ,engineering.material ,01 natural sciences ,Superconductivity (cond-mat.supr-con) ,Condensed Matter::Materials Science ,Condensed Matter::Superconductivity ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,0103 physical sciences ,010306 general physics ,Physics ,Superconductivity ,Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed matter physics ,Spins ,Condensed Matter - Superconductivity ,Skyrmion ,Diamond ,021001 nanoscience & nanotechnology ,Magnetic field ,engineering ,0210 nano-technology - Abstract
Understanding the mechanisms behind high-$T_{c}$ Type-II superconductors (SC) is still an open task in condensed matter physics. One way to gain further insight into the microscopic mechanisms leading to superconductivity is to study the magnetic properties of the SC in detail, for example by studying the properties of vortices and their dynamics. In this work we describe a new method of wide-field imaging magnetometry using nitrogen-vacancy (NV) centers in diamond to image vortices in an yttrium barium copper oxide (YBCO) thin film. We demonstrate quantitative determination of the magnetic field strength of the vortex stray field, the observation of vortex patterns for different cooling fields and direct observation of vortex pinning in our disordered YBCO film. This method opens prospects for imaging of the magnetic-stray fields of vortices at frequencies from DC to several megahertz within a wide range of temperatures which allows for the study of both high-$T_{C}$ and low-$T_{C}$ SCs. The wide temperature range allowed by NV center magnetometry also makes our approach applicable for the study of phenomena like island superconductivity at elevated temperatures (e.g. in metal nano-clusters)., Main text (4 pages, 3 figures)
- Published
- 2018
- Full Text
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16. Probing the origins of inhomogeneous broadening in nitrogen-vacancy centers with Doppler-free-type spectroscopy
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Y. Rosenzweig, Yechezkel Schlussel, and Ron Folman
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Quantum Physics ,Work (thermodynamics) ,Materials science ,Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed matter physics ,FOS: Physical sciences ,Diamond ,02 engineering and technology ,engineering.material ,021001 nanoscience & nanotechnology ,01 natural sciences ,Magnetic field ,Atomic vapor ,symbols.namesake ,Vacancy defect ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,0103 physical sciences ,engineering ,symbols ,Diamond cubic ,Quantum Physics (quant-ph) ,010306 general physics ,0210 nano-technology ,Spectroscopy ,Doppler effect - Abstract
In order to better understand the underlying fundamental physical processes in nitrogen-vacancy centers in diamond, and to realize improvements in the use of this system for technological applications, it is imperative to gain new insight into the origins of the apparent inhomogeneous broadening. In this work we make use of a novel type of spectroscopy developed specifically for this task. The pump-probe spectroscopy closely follows Doppler-free spectroscopy used in atomic vapor. We show that the origin of inhomogeneous broadening comes from local magnetic field variations in the diamond lattice., Phys. Rev. B, in print
- Published
- 2018
- Full Text
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17. Quantum complementarity of clocks in the context of general relativity
- Author
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Ron Folman, Yair Margalit, Yonathan Japha, Zhifan Zhou, and Daniel Rohrlich
- Subjects
Thought experiment ,Physics ,Quantum Physics ,Physics and Astronomy (miscellaneous) ,General relativity ,Time lag ,FOS: Physical sciences ,01 natural sciences ,Complementarity (physics) ,010305 fluids & plasmas ,Gravitation ,Theoretical physics ,Computer Science::Hardware Architecture ,ComputerSystemsOrganization_MISCELLANEOUS ,0103 physical sciences ,010306 general physics ,Quantum Physics (quant-ph) ,Quantum - Abstract
Clocks play a special role at the interface of general relativity and quantum mechanics. We analyze a clock-interferometry thought experiment and go on to theoretically derive and experimentally test a complementarity relation for quantum clocks in the context of the gravitational time lag. We study this relation in detail and discuss its application to various types of quantum clocks., Supplementary Material included. Comments welcome!
- Published
- 2018
18. Color centers in diamond as novel probes of superconductivity
- Author
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Lucas Thiel, Yechezkel Schlussel, Dominik Rohner, Louis-S. Bouchard, Dmitry Budker, Victor M. Acosta, Till Lenz, Ron Folman, and Patrick Maletinsky
- Subjects
010302 applied physics ,Superconductivity ,Materials science ,Field (physics) ,Condensed Matter - Mesoscale and Nanoscale Physics ,Magnetometer ,Condensed Matter - Superconductivity ,Diamond ,FOS: Physical sciences ,Nanotechnology ,engineering.material ,Condensed Matter Physics ,01 natural sciences ,Electronic, Optical and Magnetic Materials ,law.invention ,Superconductivity (cond-mat.supr-con) ,Magnetic imaging ,law ,High pressure ,0103 physical sciences ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,engineering ,010306 general physics ,Image resolution - Abstract
Magnetic imaging using color centers in diamond through both scanning and wide-field methods offers a combination of unique capabilities for studying superconductivity, for example, enabling accurate vector magnetometry at high temperature or high pressure, with spatial resolution down to the nanometer scale. The paper briefly reviews various experimental modalities in this rapidly developing nascent field and provides an outlook towards possible future directions., Comment: 11 pages, 8 figures. Comments are welcome
- Published
- 2018
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19. Survival of the fittest in the coherent evolution of quantum ensembles
- Author
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O. Be'er, Yair Margalit, Menachem Givon, Ron Folman, Yonathan Japha, David Groswasser, and G. Liu
- Subjects
Physics ,Quantum Physics ,Rabi cycle ,Oscillation ,Atomic Physics (physics.atom-ph) ,FOS: Physical sciences ,Fourier spectrum ,Low frequency ,01 natural sciences ,Physics - Atomic Physics ,010305 fluids & plasmas ,Rigidity (electromagnetism) ,Quantum electrodynamics ,0103 physical sciences ,010306 general physics ,Quantum Physics (quant-ph) ,Quantum ,Rabi frequency ,Coherence (physics) - Abstract
We report two novel effects in an inhomogeneous ensemble of two-level systems driven by an external field. First, we observe a rigidity of the oscillation frequency: the dominant Rabi oscillation frequency does not change with the frequency of the driving field, in contrast to the well-known law of Rabi frequency increase with growing detuning of the driving field. Second, we observe a time-dependent frequency shift of the ensemble-averaged oscillation. We show that these effects follow from the inhomogeneity of the two-level splitting across the ensemble, allowing for a distribution of local oscillations in which those with high frequencies interfere destructively and decay faster than those with a low frequency, which are the only to survive in the output signal. Hence, coherence emerges from long-lived oscillations in an inhomogeneous ensemble. We analyze the Fourier spectrum of the time-dependent oscillation signal and find a non-trivial spectral structure that is double peaked for certain parameters. We show that the effects observed in alkali vapor are universal and expected in any system with a moderate inhomogeneity driven by an external field., Comment: Phys. Rev. A, in print
- Published
- 2018
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20. Investigation of two-frequency Paul traps for antihydrogen production
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Ron Folman, Dmitry Budker, Joel Fajans, Kai Krimmel, William Bertsche, Nathan Leefer, Ferdinand Schmidt-Kaler, and Hartmut Häffner
- Subjects
Nuclear and High Energy Physics ,Antiparticle ,General Physics ,Atomic Physics (physics.atom-ph) ,FOS: Physical sciences ,Superconducting magnet ,Trapping ,01 natural sciences ,physics.atom-ph ,Atomic ,Physics - Atomic Physics ,High Energy Physics - Experiment ,010305 fluids & plasmas ,Atomic physics ,High Energy Physics - Experiment (hep-ex) ,Particle and Plasma Physics ,physics.plasm-ph ,0103 physical sciences ,Nuclear ,Physics::Atomic Physics ,Paul trap ,Physical and Theoretical Chemistry ,010306 general physics ,Antihydrogen ,Physics ,Condensed Matter::Quantum Gases ,Two-frequency ,hep-ex ,Molecular ,Condensed Matter Physics ,Physics - Plasma Physics ,Atomic and Molecular Physics, and Optics ,Charged particle ,Plasma Physics (physics.plasm-ph) ,Antiproton ,Antimatter ,Ion trap ,Ion traps - Abstract
Radio-frequency (rf) Paul traps operated with multifrequency rf trapping potentials provide the ability to independently confine charged particle species with widely different charge-to-mass ratios. In particular, these traps may find use in the field of antihydrogen recombination, allowing antiproton and positron clouds to be trapped and confined in the same volume without the use of large superconducting magnets. We explore the stability regions of two-frequency Paul traps and perform numerical simulations of small, multispecies charged-particle mixtures that indicate the promise of these traps for antihydrogen recombination., 11 pages, 10 figures
- Published
- 2017
- Full Text
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21. Using a quantum work meter to test non-equilibrium fluctuation theorems
- Author
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Shimon Machluf, Augusto J. Roncaglia, Juan Pablo Paz, Ron Folman, Federico Cerisola, Yair Margalit, and Quantum Gases & Quantum Information (WZI, IoP, FNWI)
- Subjects
Work (thermodynamics) ,Fluctuation theorems ,Science ,Ciencias Físicas ,Quantum Thermodynamics ,General Physics and Astronomy ,FOS: Physical sciences ,Quantum Work ,01 natural sciences ,Article ,General Biochemistry, Genetics and Molecular Biology ,010305 fluids & plasmas ,purl.org/becyt/ford/1 [https] ,0103 physical sciences ,Physics::Atomic Physics ,Statistical physics ,lcsh:Science ,010306 general physics ,Quantum thermodynamics ,Quantum ,Quantum fluctuation ,First law of thermodynamics ,Condensed Matter::Quantum Gases ,Physics ,Quantum Physics ,Multidisciplinary ,Internal energy ,purl.org/becyt/ford/1.3 [https] ,General Chemistry ,Astronomía ,Probability distribution ,lcsh:Q ,Quantum Physics (quant-ph) ,Random variable ,CIENCIAS NATURALES Y EXACTAS - Abstract
Non-equilibrium quantum thermodynamics is essential to describe new devices that operate far from the regime where the usual thermodynamical laws are obeyed. When quantum fluctuations dominate, defining and measuring work and heat, two central concepts in classical thermodynamics, is non-trivial. For driven, but otherwise isolated, quantum systems, work is a random variable associated with the change in the internal energy, as the first law of thermodynamics indicates. In this paper we present the design and the experimental implementation of a quantum work meter (QWM) operating on an ensemble of cold atoms. Our QWM not only directly measures work but also directly samples its probability distribution. As the work probability distribution plays a central role in the fluctuation theorems of non-equilibrium quantum thermodynamics, the QWM is an ideal tool to test their validity. In particular, we use it to verify the Jarzynski identity., Comment: Final, published version
- Published
- 2017
- Full Text
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22. Analysis of a high-stability Stern–Gerlach spatial fringe interferometer
- Author
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Yonathan Japha, Yair Margalit, Zhifan Zhou, Shimon Machluf, Ron Folman, and Samuel Moukouri
- Subjects
Physics ,Stern–Gerlach experiment ,business.industry ,Atom chip ,Wave packet ,General Physics and Astronomy ,Magnetic field gradient ,01 natural sciences ,010305 fluids & plasmas ,Improved performance ,Interferometry ,Optics ,0103 physical sciences ,010306 general physics ,business ,Order of magnitude ,Coherence (physics) - Abstract
The discovery of the Stern-Gerlach (SG) effect almost a century ago was followed by suggestions to use the effect as a basis for matter-wave interferometry. However, the coherence of splitting particles with spin by a magnetic gradient to a distance exceeding the position uncertainty in each of the arms was not demonstrated until recently, where spatial interference fringes were observed in a proof-of-principle experiment. Here we present and analyze the performance of an improved high-stability SG spatial fringe interferometer based on two spatially separate wave packets with a maximal distance that is more than an order of magnitude larger than their minimal widths. The improved performance is enabled by accurate magnetic field gradient pulses, originating from a novel atom chip configuration, which ensures high stability of the interferometer operation. We analyze the achieved stability using several models, discuss sources of noise, and detail interferometer optimization procedures. We also present a simple analytical phase-space description of the interferometer sequence that demonstrates quantitatively the complete separation of the superposed wave packets.
- Published
- 2019
- Full Text
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23. Modulation enhancement of a laser diode in an external cavity
- Author
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Menachem Givon, G. Aviv, David Groswasser, A. Waxman, and Ron Folman
- Subjects
Quantum optics ,Materials science ,Physics and Astronomy (miscellaneous) ,Laser diode ,business.industry ,General Engineering ,Physics::Optics ,General Physics and Astronomy ,Beat (acoustics) ,Optical modulation amplitude ,Semiconductor laser theory ,law.invention ,Optics ,Mode-locking ,law ,business ,Frequency modulation ,Free spectral range - Abstract
We present experimental results demonstrating enhanced current modulation of an antireflection-coated edge-emitting laser diode placed in an external cavity. By eliminating the internal cavity of the laser diode and matching the external cavity free spectral range to the modulation frequency we have increased the modulation response up to nearly complete carrier suppression. We demonstrate the tunability of this enhanced modulation over a range of more than 3 GHz. The power of the modulated beam has been measured to be 10 mW. We have recorded a beat note between the first two optical sidebands of width 1 Hz at 6.834 GHz (corresponding to the hyperfine splitting of the 87Rb ground state). This technique enables the generation of two high-power phase-locked beams for coherent manipulation of atomic states.
- Published
- 2009
- Full Text
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24. Robust spatial coherence 5$\,\mu$m from a room-temperature atom chip
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Yonathan Japha, Mark Keil, Ron Folman, David Groswasser, and Shuyu Zhou
- Subjects
Diffraction ,Physics ,Condensed Matter::Quantum Gases ,Condensed matter physics ,Atom chip ,Dephasing ,Magnetic lattice ,External noise ,01 natural sciences ,Molecular physics ,010305 fluids & plasmas ,Physics - Atomic Physics ,Spatial coherence ,Lattice (order) ,0103 physical sciences ,010306 general physics ,Electronic circuit - Abstract
We study spatial coherence near a classical environment by loading a Bose-Einstein condensate into a magnetic lattice potential and observing diffraction. Even very close to a surface (5$\,\mu$m), and even when the surface is at room temperature, spatial coherence persists for a relatively long time ($\ge$500$\,$ms). In addition, the observed spatial coherence extends over several lattice sites, a significantly greater distance than the atom-surface separation. This opens the door for atomic circuits, and may help elucidate the interplay between spatial dephasing, inter-atomic interactions, and external noise., Comment: 15 pages, 14 figures, revised for final publication. This manuscript includes in-depth analysis of the data presented in arXiv:1502.01605
- Published
- 2015
25. Suppression and enhancement of decoherence in an atomic Josephson junction
- Author
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Yonathan Japha, Mark Keil, Amichay Vardi, Shuyu Zhou, Ron Folman, and Carsten Henkel
- Subjects
Physics ,Josephson effect ,Condensed Matter::Quantum Gases ,Quantum Physics ,Quantum decoherence ,Dephasing ,General Physics and Astronomy ,Institut für Physik und Astronomie ,FOS: Physical sciences ,01 natural sciences ,Molecular physics ,Noise (electronics) ,010305 fluids & plasmas ,0103 physical sciences ,Atom ,Phase noise ,Atomtronics ,Atomic number ,Physics::Atomic Physics ,010306 general physics ,Quantum Physics (quant-ph) - Abstract
We investigate the role of interatomic interactions when a Bose gas, in a double-well potential with a finite tunneling probability (a 'Bose–Josephson junction'), is exposed to external noise. We examine the rate of decoherence of a system initially in its ground state with equal probability amplitudes in both sites. The noise may induce two kinds of effects: firstly, random shifts in the relative phase or number difference between the two wells and secondly, loss of atoms from the trap. The effects of induced phase fluctuations are mitigated by atom–atom interactions and tunneling, such that the dephasing rate may be suppressed by half its single-atom value. Random fluctuations may also be induced in the population difference between the wells, in which case atom–atom interactions considerably enhance the decoherence rate. A similar scenario is predicted for the case of atom loss, even if the loss rates from the two sites are equal. We find that if the initial state is number-squeezed due to interactions, then the loss process induces population fluctuations that reduce the coherence across the junction. We examine the parameters relevant for these effects in a typical atom chip device, using a simple model of the trapping potential, experimental data, and the theory of magnetic field fluctuations near metallic conductors. These results provide a framework for mapping the dynamical range of barriers engineered for specific applications and set the stage for more complex atom circuits ('atomtronics').
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- 2015
- Full Text
- View/download PDF
26. A self-interfering clock as a 'which path' witness
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Daniel Rohrlich, Shimon Machluf, Yair Margalit, Yonathan Japha, Ron Folman, and Zhifan Zhou
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Physics ,Quantum Physics ,Multidisciplinary ,Quantum decoherence ,General relativity ,Wave packet ,FOS: Physical sciences ,Quantum entanglement ,Topology ,Interferometry ,Superposition principle ,Computer Science::Hardware Architecture ,Path (graph theory) ,Proper time ,Quantum Physics (quant-ph) - Abstract
We experimentally demonstrate a new interferometry paradigm: a self-interfering clock. We split a clock into two spatially separated wave packets, and observe an interference pattern with a stable phase showing that the splitting was coherent, i.e., the clock was in two places simultaneously. We then make the clock wave packets "tick" at different rates to simulate a proper time lag. The entanglement between the clock's time and its path yields "which path" information, which affects the visibility of the clock's self-interference. By contrast, in standard interferometry, time cannot yield "which path" information. As a clock we use an atom prepared in a superposition of two spin states. This first proof-of-principle experiment may have far-reaching implications for the study of time and general relativity and their impact on fundamental quantum effects such as decoherence and wave packet collapse., Comment: 22 pages, 8 figures
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- 2015
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- View/download PDF
27. A Bose Einstein condensate in a microtrap
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Ron Folman, A. Kasper, Jörg Schmiedmayer, L. Feenstra, M. Bartenstein, S. Schneider, B. Engeser, Thorsten Schumm, Ch. vom Hagen, and Israel Bar-Joseph
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Condensed Matter::Quantum Gases ,Physics ,Surface (mathematics) ,SIMPLE (dark matter experiment) ,Physics and Astronomy (miscellaneous) ,Condensed matter physics ,Condensed Matter::Other ,Atomic and Molecular Physics, and Optics ,law.invention ,Homogeneous ,law ,Physics::Atomic Physics ,Atomic physics ,Bias field ,Bose–Einstein condensate - Abstract
We describe an experiment to create a sizable 87Rb Bose–Einstein condensate (BEC) in a simple magnetic microtrap, created by a current through a Z-shaped wire and a homogeneous bias field. The BEC is created close to a reflecting surface. It is an ideal coherent source for experiments with cold atoms close to surfaces, be it small-volume microtraps or directly studying the interactions between cold atoms and a warm surface.
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- 2003
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28. Quantum information processing with neutral atoms on an atom chip
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Jörg Schmiedmayer, Ron Folman, and Tommaso Calarco
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Atomic and Molecular Physics, and Optics - Published
- 2002
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29. Microwave saturation spectroscopy of nitrogen-vacancy ensembles in diamond
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Dmitry Budker, Victor M. Acosta, Mariusz Mrózek, Andrey Jarmola, Daniel S. Rudnicki, Pauli Kehayias, Ron Folman, and Wojciech Gawlik
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Materials science ,Condensed Matter - Mesoscale and Nanoscale Physics ,Atomic Physics (physics.atom-ph) ,FOS: Physical sciences ,chemistry.chemical_element ,Diamond ,engineering.material ,Condensed Matter Physics ,Nitrogen ,Physics - Atomic Physics ,Electronic, Optical and Magnetic Materials ,Magnetic field ,chemistry ,Vacancy defect ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,Saturation (graph theory) ,engineering ,Sensitivity (control systems) ,Atomic physics ,Spectroscopy ,Microwave ,Optics (physics.optics) ,Physics - Optics - Abstract
Negatively-charged nitrogen-vacancy (NV$^-$) centers in diamond have generated much recent interest for their use in sensing. The sensitivity improves when the NV ground-state microwave transitions are narrow, but these transitions suffer from inhomogeneous broadening, especially in high-density NV ensembles. To better understand and remove the sources of broadening, we demonstrate room-temperature spectral "hole burning" of the NV ground-state transitions. We find that hole burning removes the broadening caused by magnetic fields from $^{13}$C nuclei and demonstrate that it can be used for magnetic-field-insensitive thermometry., Main text: 5 pages, 4 figures. Supplement: 6 pages, 3 figures
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- 2014
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30. Phase space tomography of cold-atoms dynamics in a weakly corrugated potential
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Mark Keil, Shuyu Zhou, Yonathan Japha, Tal David, Ron Folman, Julien Chabé, David Groswasser, and Ran Salem
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Physics ,Condensed Matter::Quantum Gases ,Quantum Physics ,Tomographic reconstruction ,Quantum dynamics ,Anharmonicity ,FOS: Physical sciences ,Angular velocity ,Molecular physics ,Atomic and Molecular Physics, and Optics ,Quantum Gases (cond-mat.quant-gas) ,Ultracold atom ,Phase space ,Quantum mechanics ,Matter wave ,Physics::Atomic Physics ,Quantum Physics (quant-ph) ,Dispersion (water waves) ,Condensed Matter - Quantum Gases - Abstract
We demonstrate tomographic reconstruction of the phase space distribution of atoms oscillating in a harmonic trap with weak potential corrugation caused by nanoscale imperfections in an atom chip. We find that deformations in these distributions are highly sensitive to anharmonic components of the potential. They are explained in terms of angular velocity dispersion of isoenergetic phase space trajectories. We show that the method is applicable for probing classical and quantum dynamics of cold atoms, and we note its importance for future technological applications., 10 pages, 8 figures
- Published
- 2014
31. Miniaturizing atom optics: from wires to atom chips
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Jörg Schmiedmayer and Ron Folman
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Physics ,Atom optics ,General Physics and Astronomy ,Atom (order theory) ,Atomic physics - Abstract
On peut realiser une grande variete de potentiels de guidage ou de piegeage en approchant des atomes froids au voisinage d'objets charges ou parcourus par des courants; ceci permet la miniaturisation et l'integration d'elements d'optique atomique, Les surfaces portant ces elements forment des puces atomiques qui, pour l'optique coherente d'ondes de matiere, peuvent constituer la base de nouveaux dispositifs, similaires aux circuits integres pour l'electronique. Nous decrivons les principes de base pour la construction de tels guides et pieges microscopiques, nous indiquons comment y confiner des atomes, puis nous donnons des exemples d'experiences a base de puces atomiques.
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- 2001
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32. Atoms and wires: toward atom chips
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E. Hartungen, F. Payr, Tommaso Calarco, Albrecht Haase, Peter Krüger, Jörg Schmiedmayer, M. Bartenstein, S. Schneider, K. Brugger, Ron Folman, Björn Hessmo, Donatella Cassettari, A. Kasper, Thomas Maier, and Alexander Chenet
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Condensed Matter::Quantum Gases ,Physics ,Quantum optics ,Mesoscopic physics ,Quantum decoherence ,Quantum entanglement ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Magnetic trap ,Atom ,Physics::Atomic and Molecular Clusters ,Atom optics ,Physics::Atomic Physics ,Electrical and Electronic Engineering ,Quantum information ,Atomic physics - Abstract
Atoms can be trapped and guided using nanofabricated wires on surfaces, achieving the scales required by quantum information proposals. These atom chips form the basis for robust and widespread application of cold atoms ranging from atom optics to fundamental questions in mesoscopic physics, and possibly quantum information systems.
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- 2000
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33. Micromanipulation of neutral atoms with nanofabricated structures
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Albrecht Haase, Ron Folman, Thomas Maier, Stefan Schneider, Björn Hessmo, Peter Krüger, Tommaso Calarco, Donatella Cassettari, Alexander Chenet, and Jörg Schmiedmayer
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Condensed Matter::Quantum Gases ,Quantum optics ,Physics ,Mesoscopic physics ,Physics and Astronomy (miscellaneous) ,Energetic neutral atom ,General Engineering ,General Physics and Astronomy ,Nanotechnology ,Atom ,Atom optics ,Miniaturization ,Physics::Atomic Physics ,Quantum information ,Atomic physics ,Quantum - Abstract
A large variety of trapping and guiding potentials can be designed by bringing cold atoms close to charged or current carrying material objects. We describe the basic principles of constructing microscopic traps and guides and how to load atoms into them. The simplicity and versatility of these methods will allow for miniaturization and integration of atom optical elements into matter-wave quantum circuits on Atom Chips. These could form the basis for robust and widespread applications in atom optics, ranging from fundamental studies in mesoscopic physics to possibly quantum information systems.
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- 2000
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- View/download PDF
34. A study of parton fragmentation in hadronic Z $^0$ decays using $\Lambda\bar\Lambda$ correlations
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B. Nellen, H. G. Evans, I. Cohen, Tara Shears, Christoph Rembser, C. Hartmann, D. E. Plane, T. J. McMahon, C. Couyoumtzelis, Stephen Hillier, G. Gaycken, P. G. Bright-Thomas, J. Dubbert, G. M. Dallavalle, S. A. Robins, R. K. Carnegie, M. Schumacher, M. Herndon, M. Bobinski, R. Liebisch, K. Stoll, P. G. Estabrooks, R. K. Keeler, J. A. Wilson, J. Böhme, Andris Skuja, K. Ackerstaff, Matthias Schröder, M. Thiergen, Gregor Herten, N. K. Watson, Dave Charlton, S. Petzold, P. M. Watkins, D. Lazic, A. Macpherson, M. Fierro, Randall Sobie, G. D. Lafferty, A. J. Martin, F. Odorici, Tetsuro Mashimo, S. R. Lautenschlager, J. Grunhaus, W. Mader, Erez Etzion, C. K. Hargrove, S. Betts, M. Hapke, S. Yamashita, J. E. Pilcher, Stefan Kluth, Shlomit Tarem, Stefan Schmitt, K. Roscoe, H. A. Neal, R. Bürgin, B. Surrow, C. Y. Chang, D. R. Rust, A. W. Lloyd, P. Igo-Kemenes, Georges Azuelos, P. E.L. Clarke, O. Runolfsson, A. D. Schaile, Gabriella Pasztor, E. Tsur, P. Vannerem, M. J. Oreglia, Klaus Kurt Desch, G. W. Wilson, W. Gorn, K. Ishii, H. Jeremie, M. Hauschild, C. Markopoulos, John Allison, J. Lauber, G. Yekutieli, S. Baumann, M. Przybycień, Guenter Duckeck, Sachio Komamiya, A. T. Watson, A. A. Carter, R. Howard, M. Verzocchi, K. W. Bell, P. Taras, Ron Folman, A. M. Lee, E. von Törne, E. A. Mckigney, E. Torrence, Claudio Grandi, J. S. White, J. Pálinkás, T. P. Kokott, G. A. Snow, C. P. Ward, J. P. Martin, J. R. Carter, S. Söldner-Rembold, G. N. Patrick, R. Mir, R. Hawkings, Otmar Biebel, E. Clay, Shoji Asai, Gideon Bella, Ekg Sarkisyan, T. Saeki, R. Davis, J. C. Hill, J. Letts, M. Fanti, O. Schaile, H. J. Burckhart, Daniel Lellouch, D. I. Futyan, Jacqueline Batley, P. I. Kayal, Takehiko Mori, H. Mes, James Pinfold, R. Perez-Ochoa, R. Seuster, Giovanni Abbiendi, S. De Jong, Claire Shepherd-Themistocleous, S. Robertson, Daniele Bonacorsi, S. B. Anderson, K. Sachs, Shlomo Dado, I. P. Duerdoth, S. Braibant, Norbert Wermes, Sherry Towers, T. Kawamoto, W. J. McDonald, W. R. Gibson, B. C. Shen, Robert McPherson, M. Boutemeur, F. S. Merritt, D. M. Strom, P. Mättig, J. Gascon, S. Orito, K. Harder, F. G. Oakham, B. Schmitt, E. L. Barberio, R. E. Schmitz, R. D. Heuer, Fabrizio Fabbri, Sven Menke, D. Lanske, Siegfried Bethke, D. Liu, Giora Mikenberg, S. F. Ashby, H. Rick, V. Zacek, R. Van Kooten, Stan Bentvelsen, J. von Krogh, P. Hüntemeyer, Raimund Ströhmer, R. J. Hemingway, A. A. Faust, A. K. Honma, W. G. Scott, S. D. Talbot, J. W. Gary, C. R. Jones, D. S. Koetke, R. M. Brown, Lorne Levinson, M. F. Turner-Watson, M. Gruwé, L. A. del Pozo, Marcello Mannelli, Peter R Hobson, I. Nakamura, B. W. Kennedy, P. Jovanovic, D. M. Gingrich, P. Scharff-Hansen, J. Bechtluft, Richard Teuscher, I. J. Bloodworth, D. Zer-Zion, A. S. Turcot, F. Fiedler, P. Poffenberger, J. A. McKenna, T. R. Junk, D. Eatough, Austin Ball, Peter Krieger, A. Macchiolo, A. M. Smith, P. S. Wells, D. Glenzinski, Dezso Horvath, M. J. Losty, R. G. Kellogg, G. G. Hanson, Jean-Arcady Meyer, Terry Richard Wyatt, C. M. Hawkes, Yoram Rozen, M. Kolrep, T. Behnke, R. Bartoldus, Alessandro Montanari, T. Kuhl, H. O. Ogren, J. Polok, G. Giacomelli, I. Lawson, Richard Nisius, Christoph Geich-Gimbel, D. Karlen, A. De Roeck, M. Kobel, O. C. Cooke, Beatrix Dienes, B. List, Marco Cuffiani, P. Pfeifenschneider, M. S. Dixit, Frans Meijers, Vakhtang Kartvelishvili, J. E. Conboy, A. Fürtjes, P. Gagnon, Stefano Marcellini, L. Brigliadori, N. Altekamp, H. Voss, R. J. Barlow, A. Biguzzi, D. J. Miller, J. Patt, J. G. Layter, A. Sittler, Zoltan Laszlo Trocsanyi, André Schöning, O. Sahr, W. M. Sang, S. W. O'Neale, K. J. Anderson, S. D. Bird, D. Axen, A. Jawahery, Peter Sherwood, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Paolo Giacomelli, C. Sbarra, F. R. Jacob, M. Hansroul, Paul Kyberd, F. K. Loebinger, J. Steuerer, Ivor Fleck, C. Burgard, Joleen Pater, A. Klier, R. J. Homer, Satoshi Mihara, Kiyotomo Kawagoe, Achim Stahl, K. R. Hossain, D. C. Imrie, G. P. Siroli, K. Stephens, Christoph Schwick, C. Littlewood, V. Gibson, I. Trigger, F. Scharf, German Martinez, D. R. Ward, T. Kress, J. M. Roney, Ehud Duchovni, Koichi Nagai, J. Schieck, W. Mohr, M. Jimack, M. A. Thomson, A. Michelini, Claudia Ciocca, F. Wöckerle, E. K. U. Gross, M. Sproston, S. M. Gascon-Shotkin, Satoshi Tanaka, T. Kobayashi, A. M. Rossi, R. L. Coxe, A. Hocker, D. Chrisman, G. D. Long, Volker Blobel, Michael Hildreth, Alain Bellerive, Stephen Lloyd, N. L. Rodning, R. Kowalewski, S. Arcelli, Gideon Alexander, Paolo Capiluppi, and J. Goldberg
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Physics ,Particle physics ,Physics and Astronomy (miscellaneous) ,Electron–positron annihilation ,Hadron ,Hyperon ,Parton ,Lambda ,Lambda baryon ,Nuclear physics ,Baryon ,High Energy Physics::Experiment ,Rapidity ,Engineering (miscellaneous) - Abstract
The correlated production of \(\Lambda\) and \(\bar\Lambda\) baryons has been studied using 4.3 million multihadronic \({\rm Z}^0\) decays recorded with the Opal detector at Lep. Lambda pairs were investigated in the full data sample and for the first time also in 2-jet and 3-jet events selected with the \(k_\perp\) algorithm. The distributions of rapidity differences from correlated \(\Lambda\bar\Lambda\) pairs exhibit short-range, local correlations and prove to be a sensitive tool to test models, particularly for 2-jet events. The Jetset model describes the data best but some extra parameter tuning is needed to improve agreement with the experimental results in the rates and the rapidity spectra simultaneously. The recently developed modification of Jetset, the MOdified Popcorn Scenarium (Mops), and also Herwig do not give satisfactory results. This study of di-lambda production in 2- and 3-jet events supports the short-range compensation of quantum numbers.
- Published
- 2000
- Full Text
- View/download PDF
35. Intermittency and correlations in hadronic Z $^0$ decays
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K. Stephens, M. Schumacher, P. G. Estabrooks, F. Odorici, N. K. Watson, D. R. Rust, C. Littlewood, H. A. Neal, Otmar Biebel, P. Scharff-Hansen, P. M. Watkins, K. Hoffman, V. Gibson, Claire Shepherd-Themistocleous, A. M. Lee, J. Goldberg, Erez Etzion, Shlomit Tarem, B. Surrow, G. G. Hanson, Richard Teuscher, A. S. Turcot, N. Altekamp, H. Voss, A. Macpherson, H. O. Ogren, Christoph Geich-Gimbel, I. Trigger, F. Fiedler, Richard Keeler, D. R. Ward, A. M. Smith, P. I. Kayal, K. Stoll, G. Giacomelli, S. Yamashita, I. Lawson, R. J. Barlow, D. J. Miller, I. Cohen, Christoph Rembser, H. Mes, I. P. Duerdoth, S. Braibant, D. Axen, A. Jawahery, T. J. McMahon, A. De Roeck, M. Kobel, P. Igo-Kemenes, M. Hoch, K. Ishii, H. Jeremie, Dave Charlton, C. Couyoumtzelis, M. Fanti, S. A. Robins, M. S. Dixit, O. C. Cooke, S. Spagnolo, Andris Skuja, S. Petzold, Tetsuro Mashimo, A. A. Faust, Peter Sherwood, Alexander Wagner, R. Liebisch, K. Ackerstaff, Norbert Wermes, Sherry Towers, T. Kawamoto, Frans Meijers, J. Dubbert, P. Pfeifenschneider, M. F. Turner-Watson, I. J. Bloodworth, Vakhtang Kartvelishvili, P. Hüntemeyer, R. K. Carnegie, A. J. Martin, R. Kowalewski, J. E. Conboy, A. Fürtjes, R. Howard, P. E.L. Clarke, J. Ludwig, K. Runge, R. Mir, P. Bock, M. Kolrep, J. Patt, R. Hawkings, Satoshi Mihara, Paul Kyberd, S. Orito, S. Arcelli, M. Herndon, F. K. Loebinger, S. Baumann, J. A. Wilson, J. Böhme, Michael Hildreth, Alain Bellerive, André Schöning, Robert McPherson, J. P. Martin, O. Sahr, H. Landsman, P. Gagnon, J. Steuerer, Ivor Fleck, O. Schaile, S. Robertson, R. D. Heuer, E. A. Mckigney, Gideon Alexander, N. L. Rodning, W. Gorn, W. Mader, Paolo Capiluppi, Joleen Pater, P. Dervan, B. Poli, Peter R Hobson, S. De Jong, A. Klier, F. G. Oakham, A. Sittler, D. Zer-Zion, D. C. Imrie, C. K. Hargrove, S. Betts, Yoram Rozen, S. B. Anderson, Matthias Schröder, W. R. Gibson, Gregor Herten, R. L. Coxe, Georges Azuelos, K. Harder, Fabrizio Fabbri, A. Frey, H. Rick, E. L. Barberio, D. Lazic, A. Macchiolo, Zoltan Laszlo Trocsanyi, Dong Hee Kim, M. Hapke, A. Hocker, M. Thiergen, Gideon Bella, H. J. Burckhart, Jacqueline Batley, D. Chrisman, G. D. Long, E. Tsur, D. I. Futyan, Volker Blobel, R. J. Hemingway, T. Kuhl, J. Lauber, R. Van Kooten, S. M. Gascon-Shotkin, Paolo Giacomelli, Sven Menke, Christopher Hawkes, G. Yekutieli, M. Verzocchi, K. W. Bell, J. Pálinkás, J. Grunhaus, G. P. Siroli, M. Przybycień, Junichi Kanzaki, J. Polok, M. Boutemeur, F. S. Merritt, B. W. Kennedy, W. M. Sang, P. Jovanovic, Richard Nisius, D. Karlen, M. Hansroul, S. D. Talbot, Stan Bentvelsen, Christoph Schwick, T. Kress, M. J. Oreglia, J. E. Pilcher, Stephen Lloyd, Austin Ball, J. C. Hill, T. R. Junk, K. Graham, A. A. Carter, Ron Folman, P. S. Wells, B. List, Peter Krieger, Marco Cuffiani, Tara Shears, R. M. Brown, Ehud Duchovni, Lorne Levinson, Alessandro Montanari, W. J. McDonald, M. Jimack, B. C. Shen, A. M. Rossi, A. Biguzzi, J. G. Layter, F. Wäckerle, Terry Richard Wyatt, D. M. Gingrich, Randall Sobie, G. D. Lafferty, Giovanni Abbiendi, A. Michelini, J. R. Carter, C. R. Jones, Siegfried Bethke, D. Liu, A. K. Honma, W. G. Scott, T. Kobayashi, Juergen Thomas, J. Bechtluft, J. A. McKenna, Stefan Schmitt, G. N. Patrick, Daniele Bonacorsi, I. Nakamura, S. Rosati, R. J. Homer, C. Sbarra, F. R. Jacob, Sachio Komamiya, A. T. Watson, A. Harel, Ikuo Ueda, D. M. Strom, J. von Krogh, Guenter Duckeck, D. Glenzinski, J. Lu, Dezso Horvath, M. J. Losty, John Allison, T. P. Kokott, T. Saeki, Claudia Ciocca, K. Roscoe, Jean-Arcady Meyer, Klaus Kurt Desch, M. Gruwé, Shoji Asai, Alessandra Fanfani, R. Davis, E. Torrence, E. Clay, Achim Stahl, R. G. Kellogg, Daniel Lellouch, T. Behnke, Stefano Marcellini, A. W. Lloyd, Kiyotomo Kawagoe, G. W. Wilson, Takehiko Mori, D. E. Plane, P. Mättig, M. Hauschild, C. Markopoulos, G. M. Dallavalle, K. R. Hossain, James Pinfold, R. Perez-Ochoa, R. Seuster, J. Gascon, V. Zacek, M. A. Thomson, J. W. Gary, L. Brigliadori, Ekg Sarkisyan, E. K. U. Gross, Marcello Mannelli, M. Sproston, S. W. O'Neale, K. J. Anderson, Raimund Ströhmer, J. Letts, P. Poffenberger, German Martinez, Beatrix Dienes, J. M. Roney, C. Y. Chang, P. Taras, D. Lanske, Koichi Nagai, J. Schieck, W. Mohr, M. Fierro, S. R. Lautenschlager, K. Sachs, O. Runolfsson, Shlomo Dado, Claudio Grandi, J. S. White, Giora Mikenberg, S. F. Ashby, A. D. Schaile, Gabriella Pasztor, P. Vannerem, G. A. Snow, C. P. Ward, S. Söldner-Rembold, G. Gaycken, and P. G. Bright-Thomas
- Subjects
Physics ,Quantum chromodynamics ,Particle physics ,Annihilation ,Physics and Astronomy (miscellaneous) ,Hadron ,Monte Carlo method ,Fizikai tudományok ,Multiplicity (mathematics) ,Bose–Einstein correlations ,law.invention ,Nuclear physics ,Természettudományok ,law ,Intermittency ,High Energy Physics::Experiment ,Engineering (miscellaneous) ,Cumulant ,Particle Physics - Experiment - Abstract
A multidimensional study of local multiplicity fluctuations and multiparticle correlations of hadrons produced in Z decays is performed. The study is based on the data sample of more than 4 million events recorded with the OPAL detector at LEP. The fluctuations and correlations are analysed in terms of the normalized scaled factorial moments and cumulants up to the fifth order. The moments are observed to have intermittency-like behaviour, which is found to be more pronounced with increasing dimension. The large data sample allows for the first time a study of the factorial cumulants in e+e- annihilation. The analysis of the cumulants shows the existence of genuine multiparticle correlations with a strong intermittency rise up to higher orders. These correlations are found to be stronger in higher dimensions. The decomposition of the factorial moments into lower-order correlations that the dynamical fluctuations have important contributions from genuine many-particle correlations. The Monte Carlo models JETSET 7.4 and HERWIG 5.9 are found to reproduce the trend of the measured moments and cumulants but they underestimate the magnitudes. The results are found to be consistent with QCD jet formation dynamics, although additional contributions from other mechanisms in the hadronization process cannot be excluded. A multidimensional study of local multiplicity fluctuations and multiparticle correlations of hadrons produced in Z decays is performed. The study is based on the data sample of more than 4 million events recorded with the OPAL detector at LEP. The fluctuations and correlations are analysed in terms of the normalized scaled factorial moments and cumulants up to the fifth order. The moments are observed to have intermittency-like behaviour, which is found to be more pronounced with increasing dimension. The large data sample allows for the first time a study of the factorial cumulants in e+e- annihilation. The analysis of the cumulants shows the existence of genuine multiparticle correlations with a strong intermittency rise up to higher orders. These correlations are found to be stronger in higher dimensions. The decomposition of the factorial moments into lower-order correlations shows that the dynamical fluctuations have important contributions from genuine many-particle correlations. The Monte Carlo models JETSET 7.4 and HERWIG 5.9 are found to reproduce the trend of the measured moments and cumulants but they underestimate the magnitudes. The results are found to be consistent with QCD jet formation dynamics, although additional contributions from other mechanisms in the hadronization process cannot be excluded.
- Published
- 1999
- Full Text
- View/download PDF
36. A measurement of the product branching ratio $f ({\rm b} \to \Lambda_{\rm b}) \cdot{\rm BR} (\Lambda_{\rm b} \to \Lambda {\rm X})$ in ${\rm Z}^0$ decays
- Author
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Raimund Ströhmer, A. Harel, Ikuo Ueda, D. M. Strom, P. G. Estabrooks, R. K. Keeler, P. Poffenberger, Dave Charlton, N. K. Watson, Michael Hildreth, Sachio Komamiya, Alain Bellerive, A. T. Watson, Claire Shepherd-Themistocleous, N. L. Rodning, P. Dervan, Otmar Biebel, F. Scharf, German Martinez, W. M. Sang, Beatrix Dienes, P. M. Watkins, S. Yamashita, A. Macpherson, R. D. Heuer, T. P. Kokott, S. M. Gascon-Shotkin, P. Igo-Kemenes, M. Hoch, K. Ishii, H. Jeremie, T. J. McMahon, C. Couyoumtzelis, T. Saeki, Gideon Bella, Achim Stahl, R. Howard, T. R. Junk, J. Dubbert, P. S. Wells, R. Davis, Terry Richard Wyatt, A. M. Rossi, R. K. Carnegie, H. J. Burckhart, Jacqueline Batley, P. I. Kayal, M. Herndon, A. A. Faust, O. Schaile, R. L. Coxe, D. R. Rust, J. A. Wilson, J. Böhme, J. Lauber, C. Sbarra, Norbert Wermes, F. R. Jacob, J. Grunhaus, Sherry Towers, T. Kawamoto, S. Robertson, L. Brigliadori, M. A. Thomson, M. Boutemeur, F. S. Merritt, H. Mes, A. Hocker, E. K. U. Gross, D. Lazic, I. P. Duerdoth, S. Braibant, C. R. Jones, S. Orito, Sven Menke, O. C. Cooke, A. M. Lee, John Allison, E. von Törne, M. Sproston, D. Chrisman, G. D. Long, Volker Blobel, P. Pfeifenschneider, Kiyotomo Kawagoe, Claudia Ciocca, A. W. Lloyd, Juergen Thomas, G. W. Wilson, S. R. Lautenschlager, G. Yekutieli, J. Patt, André Schöning, P. Hüntemeyer, M. Przybycień, Stephen Lloyd, T. Kress, R. G. Kellogg, O. Sahr, J. Bechtluft, M. Fanti, A. A. Carter, S. W. O'Neale, J. A. McKenna, Ron Folman, M. Hauschild, C. Markopoulos, K. J. Anderson, Stefano Marcellini, R. Mir, R. Hawkings, O. Runolfsson, J. M. Roney, S. D. Talbot, Ehud Duchovni, C. Y. Chang, Robert McPherson, G. Gaycken, P. G. Bright-Thomas, Paul Kyberd, Giovanni Abbiendi, F. K. Loebinger, Peter R Hobson, M. Jimack, H. Landsman, Koichi Nagai, Paolo Giacomelli, Claudio Grandi, D. Zer-Zion, R. Bartoldus, M. Hansroul, J. Schieck, H. O. Ogren, M. Schumacher, Fabrizio Fabbri, P. Taras, W. Mohr, J. Steuerer, Ivor Fleck, A. Michelini, A. Macchiolo, J. S. White, Ekg Sarkisyan, K. Stephens, Joleen Pater, J. Letts, A. Klier, Christoph Geich-Gimbel, F. Odorici, S. Baumann, Daniele Bonacorsi, R. Van Kooten, E. A. Mckigney, C. Hartmann, D. E. Plane, C. Littlewood, D. Eatough, Satoshi Tanaka, H. A. Neal, T. Kobayashi, R. J. Homer, T. Behnke, V. Gibson, K. R. Hossain, Vakhtang Kartvelishvili, F. G. Oakham, J. von Krogh, T. Kuhl, B. Schmitt, K. Hoffman, E. L. Barberio, G. M. Dallavalle, F. Wäckerle, D. M. Gingrich, J. E. Conboy, A. Fürtjes, Stefan Schmitt, M. Gruwé, I. Trigger, D. R. Ward, Richard Nisius, D. Lanske, B. List, D. C. Imrie, Gregor Herten, N. Altekamp, H. Voss, R. Kowalewski, Satoshi Mihara, S. Arcelli, R. J. Barlow, D. J. Miller, K. Roscoe, J. E. Pilcher, Marco Cuffiani, P. Gagnon, Gideon Alexander, S. Spagnolo, Klaus Kurt Desch, D. I. Futyan, Paolo Capiluppi, G. P. Siroli, M. Fierro, R. J. Hemingway, E. Torrence, E. Clay, K. Sachs, Christoph Schwick, Christopher Hawkes, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, Alessandro Montanari, C. Darling, W. R. Gibson, K. Harder, W. J. McDonald, B. C. Shen, A. Sittler, Zoltan Laszlo Trocsanyi, Shlomo Dado, Dong Hee Kim, R. M. Brown, Lorne Levinson, Siegfried Bethke, D. Liu, A. K. Honma, W. G. Scott, I. Nakamura, S. D. Bird, D. Axen, A. Jawahery, Peter Sherwood, Alexander Wagner, J. Ludwig, D. Glenzinski, Shoji Asai, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, Giora Mikenberg, S. F. Ashby, K. Runge, P. Bock, I. J. Bloodworth, A. D. Schaile, Gabriella Pasztor, P. Vannerem, Georges Azuelos, E. Tsur, S. A. Robins, G. A. Snow, C. P. Ward, S. Söldner-Rembold, M. Verzocchi, Yoram Rozen, K. W. Bell, R. Liebisch, K. Ackerstaff, J. Pálinkás, J. C. Hill, J. Polok, D. Karlen, Daniel Lellouch, Erez Etzion, Takehiko Mori, Stefan Kluth, P. Mättig, Shlomit Tarem, B. Surrow, J. Goldberg, B. Nellen, I. Cohen, Christoph Rembser, Matthias Schröder, M. Thiergen, K. Graham, Tara Shears, A. J. Martin, W. Mader, C. K. Hargrove, A. Biguzzi, J. G. Layter, S. Betts, M. Hapke, P. E.L. Clarke, J. P. Martin, M. J. Oreglia, S. De Jong, H. Rick, G. G. Hanson, J. R. Carter, G. Giacomelli, I. Lawson, James Pinfold, R. Perez-Ochoa, R. Seuster, J. Gascon, G. N. Patrick, A. De Roeck, M. Kobel, V. Zacek, J. W. Gary, M. S. Dixit, Frans Meijers, D. S. Koetke, Marcello Mannelli, K. Stoll, Andris Skuja, S. Petzold, Randall Sobie, G. D. Lafferty, Tetsuro Mashimo, M. F. Turner-Watson, Guenter Duckeck, Richard Teuscher, A. S. Turcot, F. Fiedler, W. Gorn, M. Kolrep, S. B. Anderson, P. Scharff-Hansen, Stan Bentvelsen, and A. M. Smith
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Physics ,Physics and Astronomy (miscellaneous) ,Branching fraction ,High Energy Physics::Phenomenology ,High Energy Physics::Experiment ,B meson ,Atomic physics ,Lambda ,Engineering (miscellaneous) - Abstract
The product branching ratio, \(f ({\rm b} \to \Lambda_{\rm b}) \cdot{\rm BR} (\Lambda_{\rm b} \to \Lambda{\rm X})\), where \(\Lambda_{\rm b}\) denotes any weakly-decaying b–baryon, has been measured using the OPAL detector at LEP. \(\Lambda_{\rm b}\)'s are selected by the presence of energetic \(\Lambda\) particles in bottom events tagged by the presence of displaced secondary vertices. A fit to the momenta of the \(\Lambda\) particles separates signal from B meson and fragmentation backgrounds. The measured product branching ratio is \(\) Combined with a previous OPAL measurement, one obtains \(\)
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- 1999
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37. Search for anomalous photonic events with missing energy in ${\rm e}^+{\rm e}^-$ collisions at $\sqrt{s}$ = 130, 136 and 183 GeV
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Sachio Komamiya, A. T. Watson, M. Boutemeur, F. S. Merritt, F. Scharf, T. P. Kokott, J. Letts, T. Saeki, Satoshi Mihara, German Martinez, J. Bechtluft, J. A. McKenna, G. G. Hanson, P. Scharff-Hansen, R. Davis, Randall Sobie, G. D. Lafferty, K. Sachs, S. Betts, M. Hapke, M. Fanti, G. Giacomelli, M. J. Oreglia, I. Lawson, Shlomo Dado, J. R. Carter, G. N. Patrick, A. M. Smith, Dave Charlton, R. Bartoldus, A. De Roeck, W. R. Gibson, H. O. Ogren, Christoph Geich-Gimbel, N. Altekamp, H. Voss, Guenter Duckeck, J. M. Roney, Robert McPherson, J. Grunhaus, S. R. Lautenschlager, K. Stoll, Andris Skuja, D. M. Strom, Gregor Herten, K. Harder, R. J. Barlow, G. Gaycken, P. G. Bright-Thomas, R. D. Heuer, D. J. Miller, Fabrizio Fabbri, D. C. Imrie, Claire Shepherd-Themistocleous, M. Schumacher, S. Petzold, R. Bürgin, O. Runolfsson, R. M. Brown, Lorne Levinson, M. S. Dixit, Frans Meijers, Giora Mikenberg, S. F. Ashby, Koichi Nagai, J. Schieck, Tetsuro Mashimo, Achim Stahl, Vakhtang Kartvelishvili, Paul Kyberd, J. E. Conboy, A. Fürtjes, C. Y. Chang, Ehud Duchovni, W. Mohr, M. Jimack, G. P. Siroli, J. E. Pilcher, F. Odorici, R. Van Kooten, T. R. Junk, A. Biguzzi, A. A. Faust, W. Gorn, P. Taras, F. K. Loebinger, P. S. Wells, Claudio Grandi, J. S. White, Christoph Schwick, A. Michelini, J. Steuerer, J. G. Layter, A. W. Lloyd, Ekg Sarkisyan, R. J. Hemingway, C. Hartmann, S. B. Anderson, D. E. Plane, Terry Richard Wyatt, Gideon Bella, K. Stephens, Stephen Hillier, H. A. Neal, G. M. Dallavalle, Ivor Fleck, G. W. Wilson, Satoshi Tanaka, Joleen Pater, A. D. Schaile, Gabriella Pasztor, M. Hauschild, C. Markopoulos, P. Vannerem, M. A. Thomson, A. Macpherson, H. J. Burckhart, Jacqueline Batley, F. Wäckerle, C. Littlewood, B. W. Kennedy, James Pinfold, R. Perez-Ochoa, R. Seuster, P. Jovanovic, A. Klier, Austin Ball, D. M. Gingrich, T. Kobayashi, E. K. U. Gross, L. Brigliadori, V. Gibson, H. Mes, S. M. Gascon-Shotkin, Peter Krieger, J. Gascon, R. Howard, Stan Bentvelsen, M. Sproston, K. Roscoe, G. A. Snow, C. P. Ward, Alessandro Montanari, D. Lanske, M. F. Turner-Watson, I. Trigger, I. P. Duerdoth, S. Braibant, A. Macchiolo, Peter R Hobson, D. R. Rust, P. E.L. Clarke, Klaus Kurt Desch, E. Torrence, M. Kobel, S. Söldner-Rembold, D. R. Ward, T. Kress, C. M. Hawkes, R. Mir, J. P. Martin, E. Clay, Otmar Biebel, R. Kowalewski, V. Zacek, R. Hawkings, S. W. O'Neale, K. J. Anderson, D. Zer-Zion, O. C. Cooke, P. Hüntemeyer, S. Arcelli, A. M. Lee, P. I. Kayal, Georges Azuelos, P. Pfeifenschneider, T. Kuhl, John Allison, J. W. Gary, Raimund Ströhmer, Norbert Wermes, E. von Törne, Sherry Towers, T. Kawamoto, S. De Jong, E. Tsur, D. S. Koetke, Marcello Mannelli, Richard Teuscher, A. S. Turcot, C. R. Jones, S. Orito, J. Patt, Richard Nisius, A. M. Rossi, André Schöning, P. Poffenberger, M. Fierro, M. Verzocchi, K. W. Bell, H. Rick, O. Sahr, F. G. Oakham, B. List, Marco Cuffiani, F. Fiedler, J. Pálinkás, Kiyotomo Kawagoe, B. Schmitt, E. L. Barberio, Gideon Alexander, Paolo Giacomelli, M. Hansroul, Paolo Capiluppi, J. C. Hill, Beatrix Dienes, C. Burgard, R. J. Homer, R. G. Kellogg, R. L. Coxe, W. J. McDonald, B. C. Shen, A. Hocker, M. Kolrep, Siegfried Bethke, D. Liu, A. K. Honma, D. Chrisman, G. D. Long, K. R. Hossain, Stefano Marcellini, Volker Blobel, W. G. Scott, I. Nakamura, Stephen Lloyd, W. M. Sang, Claudia Ciocca, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, Michael Hildreth, Alain Bellerive, N. L. Rodning, C. Sbarra, F. R. Jacob, Daniele Bonacorsi, J. Lauber, J. von Krogh, S. D. Talbot, M. Gruwé, L. A. del Pozo, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, D. Eatough, T. Behnke, M. Bobinski, J. A. Wilson, J. Böhme, D. Lazic, P. Gagnon, G. Yekutieli, M. Przybycień, A. A. Carter, Ron Folman, A. Sittler, Zoltan Laszlo Trocsanyi, Giovanni Abbiendi, S. D. Bird, D. Axen, A. Jawahery, Peter Sherwood, Stefan Schmitt, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Shoji Asai, P. G. Estabrooks, R. K. Keeler, Daniel Lellouch, N. K. Watson, Takehiko Mori, P. Mättig, P. M. Watkins, I. J. Bloodworth, S. Baumann, Yoram Rozen, E. A. Mckigney, J. Polok, D. Karlen, D. I. Futyan, J. Goldberg, B. Nellen, H. G. Evans, I. Cohen, Christoph Rembser, Erez Etzion, Stefan Kluth, Shlomit Tarem, B. Surrow, S. A. Robins, R. Liebisch, K. Ackerstaff, A. J. Martin, S. Yamashita, P. Igo-Kemenes, K. Ishii, H. Jeremie, W. Mader, O. Schaile, C. K. Hargrove, S. Robertson, Matthias Schröder, Sven Menke, M. Thiergen, and Tara Shears
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Physics ,Particle physics ,Missing energy ,Physics and Astronomy (miscellaneous) ,Physics beyond the Standard Model ,Standard Model ,Nuclear physics ,Pair production ,Neutralino ,High Energy Physics::Experiment ,Gravitino ,Production (computer science) ,Engineering (miscellaneous) ,Energy (signal processing) - Abstract
Photonic events with large missing energy have been observed in $\mathrm e^+e^-$ collisions at centre-of-mass energies of 130, 136 and 183 GeV collected in 1997 using the OPAL detector at LEP. Results are presented for event topologies with a single photon and missing transverse energy or with an acoplanar photon pair. Cross-section measurements are performed within the kinematic acceptance of each selection. These results are compared with the expectations from the Standard Model process ${\rm e}^+{\rm e}^-\to\nu\overline{\nu}$ + photon(s). No evidence is observed for new physics contributions to these final states. Using the data at $\sqrt{s}$ = 183 GeV, upper limits on ${\sigma({\rm e^+e^-}\to{\rm XY})\cdot{\rm BR}(\rm X \to Y \gamma)}$ and ${\sigma({\rm e^+e^-}\to{\rm XX})\cdot{\rm BR}^2(\rm X \to Y \gamma)}$ are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos ( $\rm X = \nu^*, Y = \nu$ ), to neutralino production ( $\rm X={{\tilde{\chi}}^{0}}_{2}, Y={{\tilde{\chi}}^{0}}_{1}$ ) and to supersymmetric models in which $\rm X = {{\tilde{\chi}}^{0}}_{1}$ and $\rm Y=\tilde{\mathrm{G}}$ is a light gravitino.
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- 1999
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38. Measurements of flavour-dependent fragmentation functions in ${\bf Z^{0} \rightarrow{\rm q}\bar{\rm q}}$ events
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J. von Krogh, R. Bartoldus, G. Yekutieli, M. Przybycień, A. A. Carter, Ron Folman, J. Letts, M. Gruwé, L. A. del Pozo, P. G. Bright-Thomas, K. Stephens, M. Fanti, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, Daniel Lellouch, M. Bobinski, C. Y. Chang, J. A. Wilson, J. Böhme, H. O. Ogren, K. Roscoe, M. Schumacher, E. Lefebvre, D. Lazic, Takehiko Mori, P. Mättig, F. Odorici, Randall Sobie, T. Schorner, S. D. Bird, John Allison, Reda Tafirout, Klaus Kurt Desch, G. D. Lafferty, Christoph Geich-Gimbel, S. M. Gascon-Shotkin, Achim Stahl, James Pinfold, R. Perez-Ochoa, R. Seuster, C. Littlewood, V. Gibson, E. Torrence, F. Scharf, K. Sachs, Shlomo Dado, Georges Azuelos, E. Tsur, German Martinez, J. Gascon, T. R. Junk, D. Axen, P. E.L. Clarke, A. Jawahery, Robert McPherson, M. Verzocchi, H. A. Neal, I. Trigger, E. Clay, K. W. Bell, R. G. Kellogg, J. Pálinkás, D. R. Ward, T. Kress, J. C. Hill, J. P. Martin, Dave Charlton, P. G. Estabrooks, Vakhtang Kartvelishvili, Mathieu Doucet, V. Zacek, T. Behnke, W. J. McDonald, Peter Sherwood, R. K. Keeler, B. C. Shen, Stefano Marcellini, M. F. Turner-Watson, J. W. Gary, R. D. Heuer, D. S. Koetke, W. R. Gibson, Stefan Schmitt, Siegfried Bethke, J. E. Conboy, R. Kowalewski, S. De Jong, Marcello Mannelli, Fabrizio Fabbri, M. A. Thomson, A. K. Honma, W. G. Scott, Guenter Duckeck, A. Fürtjes, N. K. Watson, W. M. Sang, Kiyotomo Kawagoe, Peter R Hobson, R. Bürgin, Alexander Wagner, I. Nakamura, E. K. U. Gross, H. Mes, P. Scharff-Hansen, A. M. Rossi, K. Nagai, I. P. Duerdoth, S. Braibant, J. Ludwig, D. Zer-Zion, K. Runge, P. Bock, P. M. Watkins, M. Sproston, A. Macchiolo, O. C. Cooke, Gregor Herten, P. Pfeifenschneider, H. Rick, Shoji Asai, Giora Mikenberg, A. Joly, R. M. Brown, Lorne Levinson, A. M. Smith, S. F. Ashby, K. R. Hossain, D. R. Rust, C. M. Hawkes, D. Glenzinski, J. Patt, André Schöning, K. Stoll, Andris Skuja, M. Boutemeur, F. S. Merritt, I. J. Bloodworth, P. Hüntemeyer, S. B. Anderson, P. Gagnon, S. Petzold, C. Sbarra, Satoshi Mihara, Gideon Alexander, Dezso Horvath, M. J. Losty, F. R. Jacob, Jean-Arcady Meyer, Tetsuro Mashimo, O. Sahr, Paolo Capiluppi, J. Grunhaus, C. Hartmann, D. E. Plane, A. M. Lee, Gideon Bella, A. D. Schaile, W. Gorn, Paul Kyberd, F. K. Loebinger, A. Sittler, Stephen Hillier, E. von Törne, Gabriella Pasztor, J. M. Roney, R. L. Coxe, Zoltan Laszlo Trocsanyi, Richard Nisius, Stan Bentvelsen, M. Fierro, G. M. Dallavalle, Yoram Rozen, H. J. Burckhart, Jacqueline Batley, P. Vannerem, Michael Hildreth, J. Steuerer, Ivor Fleck, Silvia Arcelli, J. Bechtluft, B. List, J. A. McKenna, D. Lui, A. Hocker, Paolo Giacomelli, Joleen Pater, Marco Cuffiani, Richard Teuscher, G. A. Snow, A. Klier, A. S. Turcot, F. Fiedler, D. Chrisman, G. D. Long, M. Hansroul, Ekg Sarkisyan, C. P. Ward, Sachio Komamiya, N. L. Rodning, R. Van Kooten, Theodoros Geralis, J. Lauber, J. Schieck, Volker Blobel, A. T. Watson, W. Mohr, G. G. Hanson, C. Burgard, S. Söldner-Rembold, B. Poli, R. J. Homer, T. P. Kokott, Stephen Lloyd, T. Saeki, G. Giacomelli, I. Lawson, F. Wäckerle, S. D. Talbot, J. E. Pilcher, D. M. Gingrich, Alessandra Fanfani, R. Davis, Claire Shepherd-Themistocleous, Ehud Duchovni, S. Baumann, J. Polok, A. De Roeck, M. Kobel, D. Karlen, M. Kolrep, D. Eatough, M. Jimack, C. R. Jones, G. W. Wilson, A. Michelini, H. M. Fischer, E. A. Mckigney, M. S. Dixit, D. C. Imrie, P. Vikas, A. A. Faust, Frans Meijers, Satoshi Tanaka, T. Kobayashi, D. Lanske, S. Betts, M. Hapke, G. P. Siroli, S. R. Lautenschlager, A. Biguzzi, J. G. Layter, Christoph Schwick, Claudia Ciocca, O. Runolfsson, D. I. Futyan, Claudio Grandi, M. J. Oreglia, A. W. Lloyd, S. Yamashita, P. Igo-Kemenes, S. A. Robins, K. Ishii, H. Jeremie, M. Hauschild, C. Markopoulos, R. Liebisch, K. Ackerstaff, J. R. Carter, G. N. Patrick, O. Schaile, Otmar Biebel, S. Robertson, P. Taras, Raimund Ströhmer, P. Poffenberger, Beatrix Dienes, Sven Menke, S. W. O'Neale, K. J. Anderson, P. I. Kayal, Erez Etzion, Stefan Kluth, Shlomit Tarem, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, J. Goldberg, B. Nellen, H. G. Evans, I. Cohen, Christoph Rembser, P. S. Wells, Terry Richard Wyatt, A. Macpherson, A. J. Martin, C. K. Hargrove, Tara Shears, R. Howard, R. Mir, R. Hawkings, J. S. White, Matthias Schröder, M. Thiergen, D. M. Strom, F. G. Oakham, B. Schmitt, E. L. Barberio, N. Altekamp, H. Voss, R. J. Barlow, D. J. Miller, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, and Alessandro Montanari
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Quark ,Physics ,Particle physics ,Physics and Astronomy (miscellaneous) ,Meson ,010308 nuclear & particles physics ,High Energy Physics::Lattice ,Electron–positron annihilation ,High Energy Physics::Phenomenology ,Flavour ,01 natural sciences ,Bottom quark ,Charged particle ,Nuclear physics ,0103 physical sciences ,High Energy Physics::Experiment ,Charm (quantum number) ,010306 general physics ,Maxima ,Engineering (miscellaneous) - Abstract
Fragmentation functions for charged particles in \({\rm Z}^0 \rightarrow {\rm q}\bar{\rm q}\) events have been measured for bottom (b), charm (c) and light (uds) quarks as well as for all flavours together. The results are based on data recorded between 1990 and 1995 using the OPAL detector at LEP. Event samples with different flavour compositions were formed using reconstructed \({\rm D}^{*\pm}\) mesons and secondary vertices. The \(\xi_{\rm p} =\ln(1/x_{\rm p})\) distributions and the position of their maxima \(\xi_0\) are also presented separately for uds, c and b quark events. The fragmentation function for b quarks is significantly softer than for uds quarks.
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39. An upper limit for the $\tau$ –neutrino mass from $\tau\rightarrow 5\pi^{\pm}\nu_{\tau}$ decays
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R. Bartoldus, H. M. Fischer, H. O. Ogren, Christoph Geich-Gimbel, P. G. Bright-Thomas, N. Altekamp, H. Voss, Gideon Bella, M. Schumacher, E. Lefebvre, S. B. Anderson, D. J. Miller, Vakhtang Kartvelishvili, S. L. Lloyd, F. Odorici, Otmar Biebel, P. I. Kayal, A. J. Martin, Norbert Wermes, Sherry Towers, T. Kawamoto, J. E. Conboy, A. Fürtjes, S. Orito, H. A. Neal, B. C. Shen, S. W. O'Neale, H. J. Burckhart, Jacqueline Batley, Stan Bentvelsen, J. A. McKenna, Daniel Lellouch, Takehiko Mori, J. Grunhaus, P. Gagnon, J. Allison, Siegfried Bethke, A. K. Honma, W. G. Scott, I. Nakamura, Silvia Arcelli, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, P. Mättig, R. Kowalewski, Austin Ball, Peter Krieger, C. K. Hargrove, Claudia Ciocca, M. Boutemeur, F. S. Merritt, Alessandro Montanari, S. A. Robins, H. Mes, I. P. Duerdoth, A. Sittler, R. Mir, Zoltan Laszlo Trocsanyi, Matthias Schröder, J. W. Gary, K. J. Anderson, R. Hawkings, Raimund Ströhmer, J. R. Carter, P. Igo-Kemenes, T. Schorner, M. Thiergen, S. Braibant, Gideon Alexander, Paolo Capiluppi, S. Baumann, K. Ishii, H. Jeremie, S. Betts, M. Hapke, Stefan Schmitt, J. Bechtluft, R. Liebisch, K. Ackerstaff, E. A. Mckigney, James Pinfold, R. Perez-Ochoa, R. Seuster, M. J. Oreglia, G. Duckeck, C. R. Jones, F. G. Oakham, D. Glenzinski, B. Schmitt, E. L. Barberio, G. N. Patrick, G. Mikenberg, P. Hüntemeyer, J. Gascon, V. Gibson, O. Schaile, Dezso Horvath, M. J. Losty, Ehud Duchovni, R. J. Barlow, Jean-Arcady Meyer, A. D. Schaile, Gabriella Pasztor, V. Zacek, K. Roscoe, W.J. McDonald, J. Lauber, S. Robertson, M. F. Turner-Watson, F. Scharf, M. Fierro, M. Jimack, Ekg Sarkisyan, R. G. Kellogg, T. Kobayashi, P. Vannerem, German Martinez, N. K. Watson, Tara Shears, D. Lui, S. M. Gascon-Shotkin, Shoji Asai, A. Michelini, Beatrix Dienes, Peter R Hobson, D. S. Koetke, Reda Tafirout, Klaus Kurt Desch, G. D. Lafferty, D. I. Futyan, Sven Menke, Marcello Mannelli, I. J. Bloodworth, E. Torrence, Richard Teuscher, A. S. Turcot, Dave Charlton, D. Zer-Zion, K. Stoll, G. A. Snow, Andris Skuja, J. Goldberg, Claire Shepherd-Themistocleous, Stefano Marcellini, F. Fiedler, B. Nellen, C. P. Ward, S. D. Talbot, S. Petzold, C. Y. Chang, E. Clay, Sachio Komamiya, R. L. Coxe, M. Przybzien, M. A. Thomson, Theodoros Geralis, G. W. Wilson, P. G. Estabrooks, R. K. Keeler, W. M. Sang, S. Söldner-Rembold, Tetsuro Mashimo, Yoram Rozen, P. Taras, A. Hocker, R. Bürgin, P. Vikas, E. K. U. Gross, D. Eatough, D. Chrisman, G. D. Long, D. Lanske, J. Letts, A. A. Faust, W. R. Gibson, Volker Blobel, S. R. Lautenschlager, M. Sproston, T. P. Kokott, P. M. Watkins, H. G. Evans, M. Kolrep, W. Gorn, T. Saeki, S. D. Bird, I. Cohen, Georges Azuelos, T. Behnke, E. Tsur, J. Polok, A. Joly, D. Karlen, O. Runolfsson, Christoph Rembser, Alessandra Fanfani, D. Axen, R. Davis, Satoru Yamashita, M. Verzocchi, K. W. Bell, A. M. Rossi, K. Sachs, Shlomo Dado, A. Jawahery, A. Macchiolo, Claudio Grandi, P. Scharff-Hansen, J. Pálinkás, R. M. Brown, C. M. Hawkes, C. Sbarra, Lorne Levinson, Stefan Kluth, Peter Sherwood, Alexander Wagner, Shlomit Tarem, J. M. Roney, J. C. Hill, F. R. Jacob, J. Ludwig, K. Runge, Richard Nisius, A. M. Smith, P. Bock, B. List, Marco Cuffiani, S. F. Ashby, J. Schieck, W. Mohr, C. Hartmann, D. E. Plane, Stephen Hillier, Paul Kyberd, F. K. Loebinger, G. M. Dallavalle, Michael Hildreth, J. Steuerer, Ivor Fleck, N. L. Rodning, B. Poli, Joleen Pater, A. Klier, P. Poffenberger, Satoshi Mihara, K. Stephens, C. Littlewood, G. Yekutieli, T. R. Junk, I. Trigger, D. R. Ward, T. Kress, A. A. Carter, Ron Folman, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, J. Böhme, P. E.L. Clarke, J. P. Martin, D. Lazic, S. De Jong, H. Rick, J. von Krogh, M. Gruwé, L. A. del Pozo, G. G. Hanson, G. Giacomelli, I. Lawson, A. De Roeck, M. Kobel, M. S. Dixit, Frans Meijers, O. C. Cooke, P. Pfeifenschneider, J. Patt, André Schöning, O. Sahr, A. Biguzzi, J. G. Layter, Paolo Giacomelli, M. Hansroul, C. Burgard, R. J. Homer, Achim Stahl, Kiyotomo Kawagoe, R. Van Kooten, K. R. Hossain, D. C. Imrie, G. P. Siroli, Christoph Schwick, F. Wäckerle, D. M. Gingrich, D. M. Strom, M. Fanti, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, K. Nagai, Shigenori Tanaka, D. R. Rust, A. M. Lee, E. von Törne, P. S. Wells, Terry Richard Wyatt, A. T. Watson, A. Macpherson, R. J. Sobie, R. Howard, J. S. White, Gregor Herten, J. E. Pilcher, A. W. Lloyd, M. Hauschild, and C. Markopoulos
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Physics ,Particle physics ,Energy distribution ,Physics and Astronomy (miscellaneous) ,High Energy Physics::Phenomenology ,Particle identification ,Nuclear physics ,Tau neutrino ,Pi ,High Energy Physics::Experiment ,Invariant mass ,Limit (mathematics) ,Engineering (miscellaneous) ,ALEPH experiment - Abstract
An upper limit for the \(\tau\)–neutrino mass has been determined from the decay \(\tau\rightarrow 5\pi^{\pm}\nu_{\tau}\) using data collected with the OPAL detector from 1991 to 1995 in \(\rm e^{+}e^{-}\) collisions at \(\sqrt{s}\approx M_\mathrm{Z}\). A limit of 43.2 MeV at 95% CL is obtained using a two–dimensional method in the \(5\pi\) invariant mass and energy distribution from 22 selected events. Combining this result with OPAL's previously published measurement using \(\rm \tau^{+}\tau^{-}\rightarrow 3h^{\pm}\bar{\nu}_{\tau}+3h^{\mp}\nu_{\tau}\) decays, a new combined limit of \(m_{\nu_{\tau}}
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- 1998
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40. Bose-Einstein correlations of three charged pions in hadronic Z $^{\bf 0}$ decays
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Erez Etzion, Stefan Kluth, Shlomit Tarem, S. A. Robins, T. Schorner, J. Grunhaus, Tara Shears, R. Liebisch, K. Ackerstaff, Sachio Komamiya, Theodoros Geralis, A. T. Watson, T. P. Kokott, T. Saeki, Alessandra Fanfani, G. Yekutieli, Otmar Biebel, G. G. Hanson, W. R. Gibson, H. M. Fischer, M. Przybycień, M. F. Turner-Watson, Peter R Hobson, J. Goldberg, D. Zer-Zion, M. Fierro, B. Nellen, S. R. Lautenschlager, A. A. Carter, Ron Folman, G. Giacomelli, I. Lawson, M. Boutemeur, F. S. Merritt, H. G. Evans, Gideon Bella, H. J. Burckhart, I. Cohen, Christoph Rembser, A. De Roeck, M. Kobel, O. Runolfsson, M. S. Dixit, Frans Meijers, J. Letts, R. M. Brown, Lorne Levinson, Matthias Schröder, A. W. Lloyd, P. I. Kayal, P. Gagnon, W. M. Sang, Jacqueline Batley, Claudio Grandi, M. Thiergen, J. Bechtluft, J. A. McKenna, Satoshi Mihara, Ekg Sarkisyan, P. E.L. Clarke, S. Yamashita, Kiyotomo Kawagoe, J. P. Martin, Ehud Duchovni, K. Sachs, K. Roscoe, J. von Krogh, M. Hauschild, C. Markopoulos, Norbert Wermes, Sherry Towers, S. De Jong, A. Sittler, Shlomo Dado, T. Kawamoto, Zoltan Laszlo Trocsanyi, P. Vikas, M. Jimack, Claire Shepherd-Themistocleous, P. Igo-Kemenes, P. G. Estabrooks, N. K. Watson, M. Gruwé, Reda Tafirout, Klaus Kurt Desch, A. J. Martin, H. Rick, R. Bartoldus, G. W. Wilson, A. Joly, D. Lanske, S. Orito, L. A. del Pozo, Claudia Ciocca, K. Ishii, H. Jeremie, A. Michelini, E. Torrence, Achim Stahl, E. Clay, H. O. Ogren, S. Betts, M. Hapke, Giora Mikenberg, Satoshi Tanaka, T. Kobayashi, P. M. Watkins, Georges Azuelos, K. Stephens, S. D. Bird, C. Sbarra, F. R. Jacob, E. Tsur, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, C. K. Hargrove, K. Nagai, Michael Hildreth, M. Bobinski, J. A. Wilson, S. F. Ashby, K. R. Hossain, N. L. Rodning, J. Böhme, A. D. Schaile, Gabriella Pasztor, C. Hartmann, Christoph Geich-Gimbel, P. S. Wells, Vakhtang Kartvelishvili, P. Vannerem, M. Verzocchi, K. W. Bell, J. Pálinkás, J. C. Hill, O. Schaile, B. Poli, D. Axen, A. Jawahery, Stefan Schmitt, C. Littlewood, A. Biguzzi, D. E. Plane, R. L. Coxe, Silvia Arcelli, M. J. Oreglia, Stephen Hillier, D. Lui, Paul Kyberd, F. K. Loebinger, J. G. Layter, J. E. Conboy, G. M. Dallavalle, A. Fürtjes, James Pinfold, R. Perez-Ochoa, R. Seuster, W. J. McDonald, B. C. Shen, V. Gibson, D. Lazic, G. A. Snow, C. P. Ward, A. Hocker, Terry Richard Wyatt, D. R. Rust, C. R. Jones, J. Steuerer, Ivor Fleck, J. R. Carter, G. N. Patrick, Siegfried Bethke, A. K. Honma, W. G. Scott, Randall Sobie, S. M. Gascon-Shotkin, S. Söldner-Rembold, S. Baumann, S. Robertson, Joleen Pater, D. Chrisman, G. D. Long, Peter Sherwood, G. D. Lafferty, Gregor Herten, T. R. Junk, S. W. O'Neale, I. Nakamura, A. Klier, E. A. Mckigney, Volker Blobel, Alexander Wagner, I. Trigger, K. J. Anderson, Sven Menke, A. M. Rossi, J. Ludwig, Raimund Ströhmer, D. R. Ward, N. Altekamp, H. Voss, K. Runge, T. Kress, P. Bock, D. Glenzinski, Dezso Horvath, M. J. Losty, J. M. Roney, J. Lauber, Stephen Lloyd, J. E. Pilcher, Jean-Arcady Meyer, Dave Charlton, D. I. Futyan, R. J. Barlow, A. M. Lee, D. J. Miller, J. Gascon, P. Poffenberger, D. C. Imrie, John Allison, D. M. Strom, E. von Törne, R. Bürgin, S. D. Talbot, Guenter Duckeck, Paolo Giacomelli, R. Kowalewski, D. Eatough, G. P. Siroli, Shoji Asai, M. Hansroul, Christoph Schwick, Beatrix Dienes, C. Burgard, R. G. Kellogg, M. Fanti, Gideon Alexander, R. J. Homer, Paolo Capiluppi, S. B. Anderson, Daniel Lellouch, R. Mir, C. Y. Chang, R. Hawkings, A. Macpherson, Stefano Marcellini, Richard Keeler, O. C. Cooke, J. W. Gary, Takehiko Mori, P. Taras, P. Pfeifenschneider, Robert McPherson, R. Howard, D. S. Koetke, J. S. White, Mathieu Doucet, J. Patt, André Schöning, P. Mättig, R. D. Heuer, Fabrizio Fabbri, Marcello Mannelli, O. Sahr, Stan Bentvelsen, R. Van Kooten, K. Stoll, V. Zacek, F. Wäckerle, Andris Skuja, D. M. Gingrich, S. Petzold, Tetsuro Mashimo, Richard Teuscher, A. S. Turcot, F. Fiedler, F. G. Oakham, W. Gorn, B. Schmitt, E. L. Barberio, M. Kolrep, I. J. Bloodworth, P. Scharff-Hansen, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Yoram Rozen, Peter Krieger, Alessandro Montanari, A. M. Smith, J. Polok, D. Karlen, A. A. Faust, T. Behnke, A. Macchiolo, C. M. Hawkes, Richard Nisius, B. List, Marco Cuffiani, H. Mes, I. P. Duerdoth, S. Braibant, P. Hüntemeyer, R. Davis, P. G. Bright-Thomas, M. Schumacher, E. Lefebvre, F. Odorici, H. A. Neal, F. Scharf, German Martinez, M. A. Thomson, E. K. U. Gross, M. Sproston, J. Schieck, and W. Mohr
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Physics ,Particle physics ,Physics and Astronomy (miscellaneous) ,High Energy Physics::Phenomenology ,Nuclear Theory ,Hadron ,Bose–Einstein correlations ,Lambda ,Nuclear physics ,Near threshold ,Pion ,Coulomb ,High Energy Physics::Experiment ,Nuclear Experiment ,Coulomb effect ,Engineering (miscellaneous) - Abstract
Bose-Einstein Correlations (BEC) of three identical charged pions were studied in $4 \times 10^6$ hadronic ${\rm Z}^0$ decays recorded with the OPAL detector at LEP. The genuine three-pion correlations, corrected for the Coulomb effect, were separated from the known two-pion correlations by a new subtraction procedure. A significant genuine three-pion BEC enhancement near threshold was observed having an emitter source radius of $r_3 = 0.580 \pm 0.004 \mbox{ (stat.)} \pm 0.029 \mbox{ (syst.)} \mbox{ fm}$ and a strength of $\lambda_3 = 0.504 \pm 0.010 \mbox{ (stat.)}\pm 0.041 \mbox{ (syst.)}$ . The Coulomb correction was found to increase the $\lambda_3$ value by $\sim $ 9% and to reduce $r_3$ by $\sim $ 6%. The measured $\lambda_3$ corresponds to a value of $0.707 \pm 0.014 \mbox{ (stat.)} \pm 0.078 \mbox{ (syst.)}$ when one takes into account the three-pion sample purity. A relation between the two-pion and the three-pion source parameters is discussed.
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- 1998
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41. Production of ${\rm f_0}(980)$ , ${\rm f}_2(1270)$ and $\phi(1020)$ in hadronic ${\rm Z}^0$ decay
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S. Betts, S. Yamashita, M. Hapke, J. Letts, P. Igo-Kemenes, D. E. Hutchcroft, K. Ishii, H. Jeremie, K. Sachs, A. Biguzzi, A. Rooke, J. G. Layter, Paolo Giacomelli, P. S. Wells, M. J. Oreglia, Shlomo Dado, O. Schaile, M. Hansroul, S. R. Lautenschlager, Terry Richard Wyatt, R. Lahmann, D. C. Imrie, L. Brigliadori, Sven Menke, Gideon Bella, T. Behnke, J. R. Carter, C. Burgard, G. N. Patrick, Stefan Schmitt, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, H. J. Burckhart, Jacqueline Batley, H. M. Fischer, R. J. Hemingway, Giora Mikenberg, S. F. Ashby, R. W. Springer, A. Macpherson, G. P. Siroli, Otmar Biebel, R. J. Homer, B. W. Kennedy, Christoph Schwick, A. Macchiolo, Tara Shears, P. Jovanovic, C. R. Jones, W. M. Sang, Austin Ball, O. Runolfsson, N. J. Oldershaw, J. Lauber, C. M. Hawkes, Peter Krieger, P. A. Hart, Kiyotomo Kawagoe, S. W. O'Neale, Georges Azuelos, Shoji Asai, G. G. Hanson, G. Yekutieli, E. Tsur, M. Boutemeur, F. S. Merritt, K. J. Anderson, M. Verzocchi, Richard Nisius, Alessandro Montanari, Richard Teuscher, A. D. Schaile, K. W. Bell, P. I. Kayal, J. Pálinkás, Gabriella Pasztor, H. A. Neal, R. Howard, M. F. Turner-Watson, J. S. White, A. S. Turcot, F. Fiedler, G. Giacomelli, J. C. Hill, B. List, I. Lawson, Daniel Lellouch, C. Y. Chang, W. J. McDonald, Dave Charlton, A. De Roeck, P. Vannerem, U. Ruppel, A. A. Carter, Marco Cuffiani, Norbert Wermes, B. C. Shen, Peter R Hobson, H. Mes, Ron Folman, P. Taras, G. W. Wilson, D. Zer-Zion, D. Lui, K. R. Hossain, R. Bürgin, Michael Kobel, Siegfried Bethke, A. K. Honma, M. Hauschild, C. Markopoulos, U. Jost, R. Mir, R. Hawkings, M. S. Dixit, I. P. Duerdoth, W. G. Scott, Sherry Towers, I. Nakamura, C. Markus, Frans Meijers, T. Kawamoto, Claudio Grandi, S. Braibant, P. Utzat, P. Routenburg, Matthias Schröder, E. H. Vokurka, P. E.L. Clarke, J. Grunhaus, Allen Mincer, M. K. Jones, Erez Etzion, Stefan Kluth, Shlomit Tarem, Takehiko Mori, P. Mättig, J. P. Martin, G. A. Snow, C. P. Ward, A. Joly, V. Zacek, D. Glenzinski, Dezso Horvath, M. J. Losty, S. Robertson, Julie Kirk, M. Thiergen, Gregor Herten, Jean-Arcady Meyer, Ikuo Ueda, D. M. Strom, S. Orito, J. Bechtluft, Raimund Ströhmer, Daniele Bonacorsi, R. L. Coxe, S. De Jong, P. G. Estabrooks, R. K. Keeler, N. K. Watson, P. M. Watkins, S. D. Talbot, F. G. Oakham, B. Schmitt, O. C. Cooke, Claire Shepherd-Themistocleous, P. Pfeifenschneider, M. Kolrep, E. L. Barberio, J. A. McKenna, J. E. Pilcher, S. Söldner-Rembold, P. Hüntemeyer, C. Sbarra, D. Eatough, Sachio Komamiya, C. Dallapiccola, P. Poffenberger, Theodoros Geralis, A. T. Watson, Randall Sobie, G. D. Lafferty, J. Patt, André Schöning, J. von Krogh, A. A. Faust, S. A. Robins, O. Sahr, N. Altekamp, H. Voss, T. P. Kokott, M. Gruwé, R. J. Barlow, T. Saeki, D. J. Miller, R. Bartoldus, A. J. Martin, R. Davis, L. A. del Pozo, B. Stockhausen, Paul Kyberd, F. K. Loebinger, Alessandra Fanfani, K. Ackerstaff, P. Scharff-Hansen, T. J. McMahon, Beatrix Dienes, I. J. Bloodworth, A. Hocker, H. O. Ogren, J. Steuerer, C. Couyoumtzelis, Ivor Fleck, Silvia Arcelli, M. Schumacher, E. Lefebvre, S. M. Gascon-Shotkin, R. K. Carnegie, Guenter Duckeck, Satoshi Mihara, Joleen Pater, M. Herndon, Christoph Geich-Gimbel, A. Klier, M. Bobinski, J. A. Wilson, C. K. Hargrove, R. Giacomelli, A. Oh, F. Odorici, M. Fierro, P. Gagnon, S. Baumann, Ekg Sarkisyan, Yoram Rozen, S. B. Anderson, M. Foucher, D. Chrisman, G. D. Long, D. Lazic, Matthew Evans, A. M. Rossi, John Allison, P. Szymanski, E. A. Mckigney, P. W. Jeffreys, W. P. Lai, Vakhtang Kartvelishvili, K. Stephens, Junichi Kanzaki, R. G. Kellogg, J. E. Conboy, A. Fürtjes, Csaba Hajdu, D. Karlen, A. Sittler, Stefano Marcellini, J. Goldberg, J. M. Roney, Stan Bentvelsen, Lutz Feld, N. I. Geddes, Peter Schleper, Michael Hildreth, V. Gibson, N. L. Rodning, Zoltan Laszlo Trocsanyi, B. Poli, D. I. Futyan, B. Nellen, Volker Blobel, T. R. Junk, P. Vikas, D. Lanske, I. Trigger, D. R. Ward, T. Kress, A. M. Smith, S. D. Bird, D. Axen, A. Jawahery, H. G. Evans, Peter Sherwood, M. J. Goodrick, I. Cohen, Christoph Rembser, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Stephen Lloyd, James Pinfold, R. Perez-Ochoa, D. G. Fong, J. Gascon, Ehud Duchovni, M. Jimack, J. W. Gary, D. S. Koetke, A. Michelini, Marcello Mannelli, K. Stoll, Andris Skuja, T. Kobayashi, S. Petzold, Tetsuro Mashimo, W. Gorn, R. Kowalewski, R. Van Kooten, Gideon Alexander, Paolo Capiluppi, F. Wäckerle, D. M. Gingrich, M. Fanti, W. R. Gibson, Robert McPherson, Mathieu Doucet, R. M. Brown, Lorne Levinson, A. Skillman, R. D. Heuer, Reda Tafirout, Klaus Kurt Desch, Fabrizio Fabbri, E. Torrence, K. Nagai, D. R. Rust, A. M. Lee, E. von Törne, F. Scharf, German Martinez, M. A. Thomson, E. K. U. Gross, M. Sproston, J. Schieck, W. Mohr, and A. Posthaus
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Physics ,Particle physics ,Physics and Astronomy (miscellaneous) ,Meson ,Hadron ,Fragmentation function ,High Energy Physics::Experiment ,Channel analysis ,Scalar meson ,Engineering (miscellaneous) - Abstract
Inclusive production of the \({\rm f_0}(980)\), \({\rm f}_2(1270)\) and \(\phi(1020)\) resonances has been studied in a sample of 4.3 million hadronic \({\rm Z}^0\) decays from the OPAL experiment at LEP. A coupled channel analysis has been used for the \({\rm f}_0\) in simultaneous fits to the resonances in inclusive \(\pi^+\pi^-\) and \({\rm K^+K^-}\) mass spectra. Fragmentation functions are reported for the three states. Total inclusive rates are measured to be \(0.141 \pm 0.007 \pm 0.011\)\({\rm f}_0\), \(0.155\pm0.011\pm0.018\)\({\rm f}_2\) and \(0.091\pm0.002\pm0.003\)\(\phi\) mesons per hadronic \({\rm Z}^0\) decay. The production properties of the \({\rm f}_0\), including those in three-jet events, are compared with those of the \({\rm f}_2\) and \(\phi\), and with the Lund string model of hadron production. All measurements are consistent with the hypothesis that the \({\rm f_0}(980)\) is a conventional \({\rm q\bar q}\) scalar meson.
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- 1998
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42. Search for anomalous production of photonic events with missing energy in ${\rm e^+e^-}$ collisions at $\sqrt{s} = 130$ –172 GeV
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A. Klier, P. Routenburg, C. Dallapiccola, M. Hauschild, C. Markopoulos, C. Markus, G. T. Jones, E. H. Vokurka, N. Altekamp, H. Voss, S. Orito, W. Gorn, S. R. Lautenschlager, H. A. Neal, R. J. Barlow, D. J. Miller, Stefan Kluth, E. K.G. Sarkisyan, U. Ruppel, M. R. Ingram, J. Lauber, S. Betts, M. Hapke, W. J. McDonald, A. Sittler, P. G. Estabrooks, O. Runolfsson, G. W. Wilson, V. Zacek, D. E. Hutchcroft, N. J. Oldershaw, Gideon Bella, R. Howard, U. Jost, N. K. Watson, S. D. Talbot, G. Yekutieli, P. Scharff-Hansen, A. D. Schaile, H. J. Burckhart, Jacqueline Batley, C. Beeston, M. J. Oreglia, W. M. Sang, Gregor Herten, B. Wilkens, A. Biguzzi, Raimund Ströhmer, N. Rodning, P. M. Watkins, A. Rooke, J. E. Pilcher, Gabriella Pasztor, Claudio Grandi, J. Grunhaus, D. C. Imrie, P. R. Hobson, J. G. Layter, I. Nakamura, A. K. Honma, R. Van Kooten, F. G. Oakham, D. Eatough, B. Schmitt, E. L. Barberio, R. Bartoldus, D. Lui, B. Nellen, A. M. Smith, A. Oh, Paolo Capiluppi, J-P. Meyer, John Allison, Richard Keeler, R. J. Hemingway, H. O. Ogren, L. Levinson, G. D. Long, M. Schumacher, K. Stephens, G. A. Snow, C. P. Ward, E. Lefebvre, R. L. Coxe, Christoph Geich-Gimbel, J. R. Carter, Georges Azuelos, C. R. Jones, G. Mikenberg, T. Kawamoto, Stefan Schmitt, A. Macpherson, B. W. Kennedy, P. Jovanovic, R. Lahmann, Austin Ball, S. Söldner-Rembold, F. Odorici, A. Hocker, G. N. Patrick, Peter Krieger, R. G. Kellogg, P. E.L. Clarke, Alessandro Montanari, R. Davis, Silvia Arcelli, Hans-Christian Schultz-Coulon, Csaba Hajdu, D. Chrisman, R. Perez-Ochoa, G. D. Lafferty, M. Verzocchi, K. W. Bell, Otmar Biebel, H. G. Evans, M. J. Goodrick, P. Igo-Kemenes, N. I. Geddes, Michael Hildreth, P. Gagnon, M. K. Jones, J. P. Martin, J. Letts, Christoph Rembser, E. Tsur, S. Komamiya, V. Gibson, J. S. White, Stefano Marcellini, C. Hartmann, D. G. Fong, J. Gascon, D. E. Plane, S. Dado, J. Pinfold, J. C. Hill, D. Lazic, T. J. McMahon, C. Couyoumtzelis, P. Mättig, S. Asai, Vakhtang Kartvelishvili, G. P. Siroli, S. De Jong, Christoph Schwick, K. Ackerstaff, F. Fiedler, F. Wäckerle, L. Brigliadori, S. Baumann, H. Jeremie, Stephen Lloyd, Stephen Hillier, R. K. Carnegie, E. Gross, Dave Charlton, B. Poli, F. Scharf, German Martinez, I. J. Bloodworth, Peter Schleper, K. Kawagoe, J. E. Conboy, A. Fürtjes, K. Sachs, J. Goldberg, E. A. Mckigney, S. Tarem, B. C. Shen, G. M. Dallavalle, T. R. Junk, J. M. Roney, M. Fierro, J. E.G. Edwards, R. Bürgin, H. M. Fischer, A. N. Bell, D. M. Gingrich, M. Herndon, B. Dienes, I. Trigger, A. Joly, J. W. Gary, W. P. Lai, D. S. Koetke, Marcello Mannelli, Guenter Duckeck, Lutz Feld, R. Mir, M. Bobinski, Norbert Wermes, Sherry Towers, Paolo Giacomelli, J. A. Wilson, M. Hansroul, D. R. Ward, M. Jimack, Siegfried Bethke, T. Kress, W. G. Scott, A. Michelini, H. Mes, O. Schaile, P. W. Jeffreys, M. Foucher, I. P. Duerdoth, S. D. Bird, G. G. Hanson, A. M. Lee, G. Alexander, M. Boutemeur, F. S. Merritt, Richard Teuscher, S. Braibant, S. Yamashita, R. Rylko, B. Stockhausen, Paul Kyberd, F. K. Loebinger, D. I. Futyan, A. S. Turcot, C. Burgard, I. Cohen, Ivor Fleck, G. Giacomelli, S. W. O'Neale, A. Jawahery, Joleen Pater, M. F. Turner-Watson, R. W. Springer, R. J. Homer, D. Karlen, T. Saeki, P. I. Kayal, S. F. Ashby, R. Giacomelli, Sven Menke, Daniele Bonacorsi, Z. Trácsanyi, Peter Sherwood, S. Mihara, S. M. Gascon-Shotkin, M. A. Thomson, S. Robertson, D. Glenzinski, Dezso Horvath, M. J. Losty, R. Sobie, M. S. Dixit, Frans Meijers, P. S. Wells, J. Bechtluft, K. J. Anderson, M. Fanti, D. Zer-Zion, V. Blobel, J. A. McKenna, J. Ludwig, Reda Tafirout, Klaus Kurt Desch, S. A. Robins, R. Hawkings, K. Runge, P. Bock, E. Torrence, S. Petzold, Matthew Evans, A. M. Rossi, M. Kolrep, M. Sproston, Terry Richard Wyatt, C. Y. Chang, P. Vikas, D. Lanske, T. Mori, J. von Krogh, D. Lellouch, W. R. Gibson, J. E. Bloomer, D. Axen, K. R. Hossain, S. B. Anderson, J. Pálinkás, J. Kirk, P. Szymanski, P. Taras, Michael Kobel, R. M. Brown, E. von Tärne, Theodoros Geralis, A. Skillman, O. C. Cooke, P. Pfeifenschneider, A. T. Watson, L. A. del Pozo, Stan Bentvelsen, Allen Mincer, T. P. Kokott, T. Mashimo, Alessandra Fanfani, J. Patt, André Schöning, Robert McPherson, C. Sbarra, P. Huntemeyer, A. A. Carter, Ron Folman, T. Kobayashi, Mathieu Doucet, R. D. Heuer, P. Utzat, A. A. Faust, Fabrizio Fabbri, J. Schieck, D. M. Strom, E. Duchovni, W. Mohr, A. Posthaus, K. Nagai, D. R. Rust, J. Kanzaki, S. Tanaka, Tara Shears, P. A. Hart, P. Poffenberger, K. Ishii, Claire Shepherd-Themistocleous, A. Wagner, Matthias Schröder, T. Behnke, J. Steuerer, M. Thiergen, A. Macchiolo, M. Gruwé, C. M. Hawkes, Richard Nisius, Marco Cuffiani, U. Müller, A. J. Martin, C. K. Hargrove, K. Stoll, Andris Skuja, and Y. Rozen
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Physics ,Particle physics ,Missing energy ,Physics and Astronomy (miscellaneous) ,Electron–positron annihilation ,Physics beyond the Standard Model ,Standard Model ,Nuclear physics ,Pair production ,Neutralino ,High Energy Physics::Experiment ,Production (computer science) ,Engineering (miscellaneous) ,Energy (signal processing) - Abstract
Photonic events with large missing energy have been observed in \(\mathrm{e^+e^-}\) collisions at centre-of-mass energies of 130, 136, 161 and 172 GeV using the OPAL detector at LEP. Results are presented based on search topologies designed to select events with a single photon and missing transverse energy or events with a pair of acoplanar photons. In both search topologies, cross-section measurements are performed within the kinematic acceptance of the selection. These results are compared with the expectations from the Standard Model processes \({\rm e^+e^-}\to \nu\overline\nu \gamma (\gamma )\) (single-photon) and \({\rm e^+e^-}\to \nu\overline\nu \gamma \gamma (\gamma )\) (acoplanar-photons). No evidence is observed for new physics contributions to these final states. Upper limits on \(\sigma({\rm e^+e^- \to XY)\cdot BR(X\to Y\gamma })\) and \(\sigma({\rm e^+e^- \to XX)\cdot BR^2(X\to Y\gamma })\) are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos (\({\rm X}= \nu^*,{\rm Y}= \nu\)), to neutralino production (\({\rm X}=\tilde\chi^0_2, {\rm Y}=\tilde\chi^0_1\)), and to supersymmetric models in which \({\rm X}= \tilde\chi^0_1\) and \({\rm Y}=\tilde{\rm G}\) is a light gravitino. For the latter scenario, the results of the acoplanar-photons search are used to provide mode l-dependent lower limits on the mass of the lightest neutralino.
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- 1998
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43. Multi-photon final states in e+e− collisions at ∝s =130-172 GeV
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S. Petzold, G. D. Long, Tetsuro Mashimo, J. M. Roney, Anna Macchiolo, W. Gorn, Gabriella Pasztor, S. D. Bird, P. E. L. Clarke, W. Mohr, A. Posthaus, Matthias Schröder, G. A. Snow, S. R. Lautenschlager, H. A. Neal, M. Jimack, C. P. Ward, John Allison, B. Schmitt, K. Nagai, Eduardo Ros, N. K. Watson, S. M. Gascon-Shotkin, M. Thiergen, D. L. Rees, S. Söldner-Rembold, Kiyotomo Kawagoe, S. J. De Jong, Satoshi Mihara, Daniel Lellouch, Hildreth, P. Scharff-Hansen, C.J. Beeston, A. P. Wagner, Frank Fiedler, D. Axen, S. Komamiya, A. Jawahery, David G. Charlton, Gideon Bella, BT Bouwens, Rick J. Van Kooten, Eugene P. Gross, F. Wäckerle, Paolo Giacomelli, Takehiko Mori, H. J. Burckhart, Jacqueline Batley, M. Hansroul, Georges Azuelos, E. Tsur, C. M. Hawkes, S. H. Robertson, J. Goldberg, B. Nellen, N. J. Oldershaw, E. Lefebvre, J. Steuerer, A. M. Rossi, Isabel Marian Trigger, K. W. Bell, F. Scharf, German Martinez, Gideon Alexander, Otmar Biebel, Marco Verzocchi, R. Bartoldus, J. W. Gary, J. Palinkas, K. Sachs, F. Odorici, R. G. Kellogg, C. H. Shepherd-Themistocleous, R. J. Homer, D. S. Koetke, Csaba Hajdu, Stefano Marcellini, James Letts, A. D. Schaile, A. S. Turcot, P. Igo-Kemenes, Gy. Wolf, Shigenori Tanaka, Shlomo Dado, K. Ishii, K. R. Hossain, Paolo Capiluppi, P.A. Hart, H. Jeremie, H. O. Ogren, J. C. Hill, R. J. Teuscher, A. M. Smith, A. Michelini, V. Kartvelishvili, S. A. Robins, D. Rigby, R. J. Hemingway, Christoph Geich-Gimbel, D. R. Rust, J. Ludwig, B. C. Shen, K. Runge, P. Bock, J. R. Carter, P. I. Kayal, T. Behnke, Siegfried Bethke, G. Duckeck, W. G. Scott, P. G. Estabrooks, V. Gibson, H. G. Evans, P. Szymanski, M. J. Goodrick, Doug Gingrich, J. A. McKenna, I. Cohen, P. Jovanovic, I. J. Bloodworth, James Pinfold, I. Nakamura, R. Perez-Ochoa, E. do Couto e Silva, Ehud Duchovni, E. von Törne, C. R. Jones, Richard Nisius, U. Müller, T. Kress, Peter Krieger, D. G. Fong, Carla Sbarra, J. Gascon, P. Gagnon, Dezso Horvath, M. J. Losty, Sven Menke, Alessandro Montanari, A. J. Martin, K. Ackerstaff, P. M. Watkins, Takayuki Saeki, Jean-Arcady Meyer, Sherry Towers, T. Kawamoto, Marco Cuffiani, N. L. Rodning, A. Skillman, D. E. Hutchcroft, C. Dallapiccola, M. Kolrep, D. Karlen, Carsten Daniel Burgard, B. Poli, G. Mikenberg, O. Schaile, I. P. Duerdoth, Yoram Rozen, V. Zacek, A. Sittler, S. Orito, A. K. Honma, N. Altekamp, M. Foucher, Claudio Grandi, Peter Schleper, C. K. Hargrove, Zoltan Laszlo Trocsanyi, S. J. Hillier, Tara Shears, Robert McPherson, B. Stockhausen, P. Kyberd, P. Hüntemeyer, S. B. Anderson, F. K. Loebinger, D. J. Miller, A. H. Ball, Silvia Arcelli, M. F. Turner-Watson, Meirin Oan Evans, D. C. Imrie, Mathieu Doucet, M. Hapke, R. Bürgin, Marcello Mannelli, D. M. Strom, Matthew Herndon, Fabrizio Fabbri, M. Morii, Markus Schumacher, E.K.G. Sarkisian, H. Voss, G. W. Wilson, Peter R Hobson, Ivor Fleck, G. P. Siroli, S. Baumann, M. J. Pearce, U. Jost, R. Mir, Stan Bentvelsen, Christoph Schwick, J.A. Lauber, M. J. Oreglia, H. Mes, D Chrisman, E. A. Mckigney, S. Braibant, J. E. Conboy, S. D. Talbot, M. Sproston, Joleen Pater, Peter Sherwood, D. Zer-Zion, W. P. Lai, A. Fürtjes, Stefan Kluth, T. Geralis, R. D. Heuer, Shlomit Tarem, F. G. Oakham, Stefan Schmitt, Norbert Wermes, G. N. Patrick, E. L. Barberio, A. Klier, D. Eatough, R. Giacomelli, G. D. Lafferty, D. I. Futyan, Volker Blobel, P. Routenburg, T. R. Wyatt, Jochen Schieck, T. R. Junk, M. Gruwe, Hans-Christian Schultz-Coulon, Thomson, M. J. Kobel, P. Mättig, Shoji Asai, Stephen Lloyd, A. A. Faust, D. Glenzinski, Satoru Yamashita, Robert M Brown, Gregor Herten, R. Rylko, Robert Wayne Springer, M. Boutemeur, M. Fierro, J. E.G. Edwards, F. S. Merritt, T. P. Kokott, Dixit, P. W. Jeffreys, P. S. Wells, David E. Plane, B. Wilkens, J. E. Bloomer, T. Kobayashi, A. M. Lee, A. Macpherson, Richard Keeler, P. Vikas, R. J. Sobie, Robert Lahmann, R. Howard, J. S. White, Alexander Oh, J. E. Pilcher, D. Lanske, J. Bechtluft, M. Hauschild, C. Markus, G. T. Jones, E. H. Vokurka, P R Poffenberger, J. Grunhaus, C. Hartmann, H. Fischer, O. Runolfsson, Alan Watson, Matthew Jones, Reda Tafirout, Klaus Kurt Desch, W. R. Gibson, A. Joly, Lorne Levinson, B. W. Kennedy, N. I. Geddes, Roger Barlow, K. Stephens, W.John McDonald, D. Lazic, D. R. Ward, U. Ruppel, M. R. Ingram, C. Y. Chang, P. Taras, G. Yekutieli, Allen Mincer, Marcello Fanti, Julie Kirk, P. Pfeifenschneider, A. A. Carter, Ron Folman, J. Patt, André Schöning, G. G. Hanson, G.Marco Dallavalle, P. Utzat, Beatrix Dienes, L. Brigliadori, G. Giacomelli, Daniele Bonacorsi, O. C. Cooke, S. W. O'Neale, R. Davies, P. Schenk, K. J. Anderson, J. von Krogh, Frans Meijers, R. J. Hawkings, L. A. del Pozo, A. Biguzzi, A. Rooke, J. G. Layter, T. J. McMahon, R. K. Carnegie, M. Bobinski, J. A. Wilson, J.P. Martin, A. N. Bell, K. Stoll, and Andris Skuja
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Nuclear physics ,Physics ,Particle physics ,Angular distribution ,Physics and Astronomy (miscellaneous) ,Electron–positron annihilation ,Engineering (miscellaneous) - Published
- 1998
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44. Production of P-wave charm and charm-strange mesons in hadronic Z $^0$ decays
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Matthias Schröder, D. L. Rees, M. A. Thomson, E. K. U. Gross, M. Sproston, F. Scharf, G. G. Hanson, German Martinez, M. Thiergen, Hans-Christian Schultz-Coulon, Randall Sobie, G. Giacomelli, J. Letts, Michael Schulz, G. D. Lafferty, H. M. Fischer, J. Schieck, W. Mohr, Ekg Sarkisyan, M. Fanti, A. Posthaus, J. Lauber, L. Brigliadori, K. Stoll, Gideon Bella, R. W. Springer, H. Mes, I. P. Duerdoth, Otmar Biebel, H. J. Burckhart, J. Grunhaus, P. W. Jeffreys, K. Sachs, Shlomo Dado, Andris Skuja, Jacqueline Batley, J. Goldberg, B. Nellen, S. Petzold, Tetsuro Mashimo, Tara Shears, P. A. Hart, Daniel Lellouch, Robert McPherson, Takehiko Mori, Mathieu Doucet, Guenter Duckeck, P. G. Estabrooks, D. Chrisman, G. D. Long, Volker Blobel, S. D. Talbot, S. W. O'Neale, S. Yamashita, P. Igo-Kemenes, K. Ishii, H. Jeremie, Stephen Lloyd, R. D. Heuer, Robert M Brown, Fabrizio Fabbri, M. J. Pearce, V. Zacek, K. J. Anderson, Georges Azuelos, Reda Tafirout, Klaus Kurt Desch, Kiyotomo Kawagoe, A. Joly, R. Van Kooten, D. Eatough, N. K. Watson, E. Tsur, H. G. Evans, Giora Mikenberg, W. Gorn, C. R. Jones, M. J. Goodrick, P. M. Watkins, Claire Shepherd-Themistocleous, S. B. Anderson, M. Verzocchi, P. Szymanski, Norbert Wermes, K. W. Bell, Sherry Towers, I. Cohen, P. Poffenberger, O. Schaile, M. Schumacher, E. do Couto e Silva, C. Sbarra, E. Lefebvre, P. Vikas, J. Pálinkás, T. Kawamoto, S. Braibant, W. R. Gibson, F. Odorici, A. D. Schaile, F. Wäckerle, N. I. Geddes, D. Lanske, D. M. Gingrich, M. F. Turner-Watson, Michael Hildreth, M. Morii, J. C. Hill, P. Gagnon, Gabriella Pasztor, B. T. Bouwens, Sven Menke, U. Müller, Peter R Hobson, S. Orito, M. Rosvick, John Allison, Dave Charlton, P. Scharff-Hansen, S. R. Lautenschlager, Stan Bentvelsen, W. J. McDonald, N. L. Rodning, H. A. Neal, B. C. Shen, D. Zer-Zion, A. J. Martin, Lorne Levinson, A. Sittler, P. Routenburg, P. Berlich, M. Hapke, B. Poli, K. Nagai, G. A. Snow, C. P. Ward, Sachio Komamiya, Peter Schleper, Gideon Alexander, Theodoros Geralis, A. A. Faust, Stefan Kluth, A. Skillman, R. Bürgin, P. Pfeifenschneider, Paolo Capiluppi, Stefan Schmitt, E. Ros, Siegfried Bethke, T. Hilse, D. R. Rust, D. E. Hutchcroft, R. Lahmann, Shlomit Tarem, A. K. Honma, Silvia Arcelli, D. C. Imrie, C. Y. Chang, S. Söldner-Rembold, A. M. Smith, R. G. Kellogg, C. Hartmann, U. Ruppel, M. R. Ingram, W. G. Scott, Richard Teuscher, A. S. Turcot, O. Runolfsson, D. E. Plane, I. Nakamura, T. P. Kokott, C. K. Hargrove, Stephen Hillier, J. Patt, G. M. Dallavalle, André Schöning, T. Behnke, Csaba Hajdu, F. Fiedler, A. M. Lee, T. Saeki, M. J. Oreglia, P. Taras, E. von Törne, Michael Kobel, S. D. Bird, P. Schenk, Ehud Duchovni, Alan Watson, Stefano Marcellini, G. P. Siroli, C. Beeston, Christoph Schwick, S. Baumann, D. Axen, M. Jimack, S. A. Robins, James Pinfold, A. Jawahery, Claudio Grandi, S. M. Gascon-Shotkin, P. Mättig, D. Glenzinski, J. R. Carter, G. N. Patrick, Allen Mincer, E. A. Mckigney, Gunter Wolf, Julie Kirk, D. G. Fong, A. Michelini, K. Ackerstaff, Dezso Horvath, M. J. Losty, J. Gascon, M. Kolrep, A. Macchiolo, Shoji Asai, B. Stockhausen, Paul Kyberd, F. K. Loebinger, W. P. Lai, Peter Sherwood, Jean-Arcady Meyer, Satoshi Tanaka, J. Steuerer, M. Gruwé, C. M. Hawkes, K. Stephens, Ivor Fleck, I. J. Bloodworth, Alexander Wagner, T. Kobayashi, J. Ludwig, Joleen Pater, J. W. Gary, Paolo Giacomelli, D. S. Koetke, M. Hansroul, K. Runge, P. Bock, A. Klier, Marcello Mannelli, R. Giacomelli, V. Gibson, Richard Nisius, J. M. Roney, C. Burgard, Marco Cuffiani, Yoram Rozen, T. R. Junk, D. I. Futyan, R. J. Homer, I. Trigger, M. Foucher, M. Fierro, J. E.G. Edwards, D. R. Ward, T. Kress, Matthew Evans, D. Karlen, A. M. Rossi, U. Jost, R. Mir, R. Hawkings, F. G. Oakham, B. Schmitt, E. L. Barberio, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, Alessandro Montanari, C. Dallapiccola, N. Altekamp, H. Voss, R. J. Barlow, D. J. Miller, S. Robertson, Gregor Herten, B. Wilkens, J. E. Pilcher, G. W. Wilson, M. Hauschild, C. Markus, G. T. Jones, E. H. Vokurka, N. J. Oldershaw, M. S. Dixit, Frans Meijers, A. Biguzzi, A. Rooke, J. G. Layter, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, H. Przysiezniak, A. N. Bell, G. Yekutieli, A. A. Carter, Ron Folman, P. Utzat, Daniele Bonacorsi, O. C. Cooke, J. von Krogh, L. A. del Pozo, T. J. McMahon, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, D. Lazic, A. Macpherson, Richard Keeler, R. Bartoldus, R. Howard, J. S. White, H. O. Ogren, Christoph Geich-Gimbel, J. E. Conboy, Vakhtang Kartvelishvili, A. Fürtjes, M. Boutemeur, F. S. Merritt, D. M. Strom, J. Bechtluft, J. A. McKenna, R. Rylko, P. S. Wells, Terry Richard Wyatt, and J. E. Bloomer
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Physics ,Particle physics ,Physics and Astronomy (miscellaneous) ,Meson ,Electron–positron annihilation ,High Energy Physics::Phenomenology ,Hadron ,Hadronization ,Nuclear physics ,Excited state ,High Energy Physics::Experiment ,Astrophysics::Earth and Planetary Astrophysics ,Nuclear Experiment ,Particle Physics - Experiment ,K channels - Abstract
Results are presented on the production of excited charm and excited charm-strange mesons in hadronic Z(0) decays. The results are obtained from approximately 4.3 million hadronic Z(0) decays, collected on or near the Z(0) resonance using the OPAL detector at LEP. The D-1(0)(2420) and D*(0)(2)(2460) mesons are reconstructed in the D*(+)pi(-) final state and their separate production rates in charm fragmentation and in weak decays of b-hadrons are determined. Assuming that the decay widths of these mesons are saturated by the allowed D*pi and D pi final states, the charm hadronization fractions and the inclusive branching ratios of b-hadrons to these neutral P-wave charm mesons are determined to bef(c --> D-1(0)) = 0.021 +/- 0.007(stat) +/- 0.003(syst), f(c --> D*(0)(2)) = 0.052 +/- 0.022(stat)+/- 0.013(syst), f(b --> D-1(0)) = 0.050 +/- 0.014(stat) +/- 0.006(syst), f(b --> D*(0)(2)) = 0.047 +/- 0.024(stat) +/- 0.013(syst).We also present the first observation at LEP of the D-s1(+)(2536) meson which is reconstructed in both the D*K-+(s)0 and D*K-0(+) final states After correcting for the expected contribution from bb events, assuming that the D*K channels saturate the available final states, these results are used to derive the charm hadronization fraction f(c --> D-s1(+)):f(c --> D-s1(+)) = 0.016 +/- 0.004(stat) +/- 0.003(syst).
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- 1997
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45. Search for CP violation in Z $^0\longrightarrow{\tau^+\tau^-}$ and an upper limit on the weak dipole moment of the $\tau$ lepton
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M. Schumacher, E. Lefebvre, G. W. Wilson, M. Hauschild, S. A. Wotton, C. Markus, G. T. Jones, E. H. Vokurka, F. Odorici, I. J. Bloodworth, A. S. Turcot, F. Fiedler, D. Rigby, R. J. Hemingway, B. W. Kennedy, Yoram Rozen, P. Jovanovic, Austin Ball, Peter Krieger, O. C. Cooke, M. Foucher, R. W. Springer, Manuella Vincter, Alessandro Montanari, M. Kolrep, Matthias Schröder, N. K. Watson, D. Karlen, J. von Krogh, H. Mes, Hans-Christian Schultz-Coulon, I. P. Duerdoth, P. Fath, C. Dallapiccola, Gunter Wolf, K. Ackerstaff, Randall Sobie, A. Biguzzi, Michael Schulz, G. D. Lafferty, Georges Azuelos, N. Altekamp, M. Thiergen, E. Tsur, H. Lafoux, R. J. Barlow, J. M. Roney, Claire Shepherd-Themistocleous, R. Bartoldus, M. Verzocchi, D. J. Miller, Stefan Schmitt, R. J. Hawkings, S. Yamashita, K. W. Bell, P. Igo-Kemenes, J. Pálinkás, K. Ishii, J. Lauber, H. O. Ogren, H. Jeremie, Christoph Geich-Gimbel, L. A. del Pozo, U. Jost, R. Mir, R. E. Hughes-Jones, T. J. Smith, J. C. Hill, K. Stephens, Misao Sasaki, R. Lahmann, Guenter Duckeck, D. C. Imrie, W. Mohr, W. J. McDonald, B. C. Shen, Gideon Bella, H. J. Burckhart, Jacqueline Batley, Paolo Giacomelli, A. Posthaus, P. Mättig, Shoji Asai, V. Gibson, O. Schaile, E. do Couto e Silva, Siegfried Bethke, F. Strumia, S. D. Talbot, G. P. Siroli, A. K. Honma, M. Hansroul, B. Nijjhar, W. G. Scott, T. J. McMahon, Daniel Lellouch, F. G. Oakham, I. Nakamura, Takehiko Mori, B. Schmitt, Abish Malik, T. R. Junk, C. Hartmann, T. Omori, I. Trigger, F. X. Gentit, E. L. Barberio, Kiyotomo Kawagoe, Sven Menke, D. R. Ward, T. Kress, D. E. Plane, S. B. Anderson, P. Szymanski, C. Burgard, Stefan Kluth, R. J. Homer, Shlomit Tarem, U. Müller, V. Zacek, Stephen Hillier, G. M. Dallavalle, J. E. Conboy, D. Chrisman, A. Fürtjes, A. J. Martin, U. Ruppel, M. R. Ingram, R. K. Carnegie, Volker Blobel, T. Behnke, C. R. Jones, M. Herndon, M. Bobinski, J. A. Wilson, D. Glenzinski, Dezso Horvath, M. J. Losty, D. Axen, A. Jawahery, Stan Bentvelsen, Achim Stahl, A. I. McNab, J. Goldberg, Jean-Arcady Meyer, Stephen Lloyd, D. L. Rees, James Pinfold, M. Boutemeur, F. S. Merritt, D. G. Fong, C. Lewis, M. Gruwé, Dave Charlton, A. Wagner, Peter Sherwood, C. M. Hawkes, B. Nellen, C. K. Hargrove, Tara Shears, F. Scharf, J. Gascon, R. Bürgin, German Martinez, J. Ludwig, P. A. Hart, D. Lazic, C. Sbarra, K. Runge, P. Bock, J. W. Gary, J. Bechtluft, J. A. McKenna, Richard Nisius, H. G. Evans, Reda Tafirout, Klaus Kurt Desch, M. J. Goodrick, I. Cohen, M. J. Pearce, D. S. Koetke, Marcello Mannelli, W. Matthews, Marco Cuffiani, K. Ametewee, M. A. Thomson, G. Yekutieli, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, P. Pfeifenschneider, E. K. U. Gross, A. Gaidot, J. Patt, Gideon Alexander, Paolo Capiluppi, P. Gagnon, A. A. Carter, Ron Folman, Roger Jones, M. Sproston, W. Gorn, B. J. King, P. Utzat, P. Scharff-Hansen, A. M. Smith, A. Sittler, G. Vasseur, W. R. Gibson, Ehud Duchovni, B. T. Bouwens, M. Jimack, H. M. Bosch, A. Michelini, R. M. Brown, Lorne Levinson, Satoshi Tanaka, T. Kobayashi, A. Skillman, M. F. Turner-Watson, M. Morii, Peter R Hobson, R. Van Kooten, P. Routenburg, F. Wäckerle, D. M. Gingrich, P. Berlich, K. Nagai, J. Grunhaus, D. R. Rust, A. M. Lee, Sachio Komamiya, H. M. Fischer, E. von Törne, Theodoros Geralis, E. Ros, A. T. Watson, T. P. Kokott, S. A. Robins, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, S. M. Gascon-Shotkin, Matthew Evans, A. M. Rossi, T. Tsukamoto, N. I. Geddes, Michael Hildreth, N. L. Rodning, B. Poli, S. R. Lautenschlager, B. Stockhausen, Paul Kyberd, F. K. Loebinger, H. A. Neal, J. Steuerer, Joleen Pater, T. Hilse, R. Giacomelli, O. Runolfsson, C. Beeston, A. Joly, Claudio Grandi, John Allison, R. G. Kellogg, M. Steiert, Csaba Hajdu, Stefano Marcellini, M. Fierro, J. E.G. Edwards, Ekg Sarkisyan, P. W. Jeffreys, J. J. Ward, P. Vikas, D. Lanske, Silvia Arcelli, E. A. Mckigney, W. P. Lai, P. Schenk, P. G. Estabrooks, R. K. Keeler, N. J. Oldershaw, P. M. Watkins, S. Robertson, Gregor Herten, B. Wilkens, J. E. Pilcher, P. Poffenberger, K. Sachs, Shlomo Dado, Giora Mikenberg, P. Schütz, S. Braibant, A. D. Schaile, Gabriella Pasztor, G. A. Snow, C. P. Ward, S. Söldner-Rembold, R. Howard, J. S. White, C. Y. Chang, D. M. Strom, P. Taras, Michael Kobel, R. Rylko, P. S. Wells, Terry Richard Wyatt, Julie Kirk, J. E. Bloomer, S. W. O'Neale, K. J. Anderson, Otmar Biebel, J. Letts, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, M. Rosvick, M. Hapke, D. E. Hutchcroft, M. J. Oreglia, J. R. Carter, G. N. Patrick, G. G. Hanson, G. Giacomelli, M. S. Dixit, Frans Meijers, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, H. Przysiezniak, A. N. Bell, A. Rooke, and J. G. Layter
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Quark ,Physics ,Dipole ,Particle physics ,Physics and Astronomy (miscellaneous) ,Electron–positron annihilation ,Moment (physics) ,CP violation ,Limit (mathematics) ,Electron ,Lepton - Published
- 1997
- Full Text
- View/download PDF
46. Study of $\phi(1020)$ , ${\rm D}^{*\pm}$ and B $^*$ spin alignment in hadronic Z $^0$ decays
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Achim Stahl, P. Pfeifenschneider, J. Patt, Paolo Giacomelli, M. Hansroul, C. Burgard, R. J. Homer, Ekg Sarkisyan, P. W. Jeffreys, W. R. Gibson, J. J. Ward, P. Vikas, D. Lanske, S. R. Lautenschlager, H. A. Neal, B. T. Bouwens, T. Hilse, O. Runolfsson, R. M. Brown, A. Joly, Lorne Levinson, C. Beeston, Claudio Grandi, Dave Charlton, O. C. Cooke, A. Skillman, Claire Shepherd-Themistocleous, R. Lahmann, R. Bürgin, Reda Tafirout, Klaus Kurt Desch, D. C. Imrie, J. von Krogh, Gideon Bella, H. J. Burckhart, Jacqueline Batley, A. A. Faust, T. Omori, C. R. Jones, Abish Malik, C. Hartmann, D. E. Plane, G. P. Siroli, L. A. del Pozo, Stephen Hillier, U. Jost, G. M. Dallavalle, R. Mir, R. Hawkings, G. Yekutieli, Hans-Christian Schultz-Coulon, Alan Watson, S. G. Clowes, A. Biguzzi, A. Rooke, Randall Sobie, Michael Schulz, G. D. Lafferty, J. G. Layter, S. Yamashita, A. A. Carter, Ron Folman, Roger Jones, F. G. Oakham, T. Behnke, M. Fierro, J. E.G. Edwards, P. Igo-Kemenes, B. Schmitt, E. L. Barberio, J. Letts, K. Ishii, H. Jeremie, P. E.L. Clarke, M. K. Jones, P. Utzat, S. D. Bird, Kiyotomo Kawagoe, F. X. Gentil, A. Macchiolo, M. Gruwé, C. M. Hawkes, R. E. Hughes-Jones, C. Dallapiccola, J. P. Martin, P. Schenk, S. De Jong, U. Müller, T. J. McMahon, Guenter Duckeck, Richard Nisius, D. Axen, O. Schaile, A. J. Martin, K. Sachs, I. J. Bloodworth, Shlomo Dado, R. K. Carnegie, M. Herndon, A. Jawahery, H. Przysiezniak, Marco Cuffiani, E. do Couto e Silva, A. N. Bell, N. Altekamp, Peter Sherwood, K. Ametewee, Sven Menke, Yoram Rozen, R. J. Barlow, H. Mes, I. P. Duerdoth, Gideon Alexander, Alexander Wagner, G. G. Hanson, D. J. Miller, M. Foucher, Paolo Capiluppi, C. K. Hargrove, Tara Shears, J. Ludwig, P. Fath, K. Runge, P. Bock, C. Sbarra, P. A. Hart, Ehud Duchovni, J. Lauber, G. Giacomelli, Otmar Biebel, D. Karlen, M. J. Pearce, M. Jimack, M. S. Dixit, Frans Meijers, A. Michelini, B. Stockhausen, Paul Kyberd, F. K. Loebinger, W. J. McDonald, Daniel Lellouch, S. M. Gascon-Shotkin, B. C. Shen, D. Rigby, R. J. Hemingway, Giora Mikenberg, J. Steuerer, Satoshi Tanaka, T. Kobayashi, Takehiko Mori, Matthias Schröder, Joleen Pater, Siegfried Bethke, A. K. Honma, B. Nijjhar, V. Zacek, W. G. Scott, M. Thiergen, H. Lafoux, S. D. Talbot, I. Nakamura, R. Giacomelli, B. W. Kennedy, M. Schumacher, E. Lefebvre, P. Jovanovic, James Pinfold, D. Eatough, S. B. Anderson, S. Braibant, A. D. Schaile, P. Szymanski, Gabriella Pasztor, Matthew Evans, D. Chrisman, G. D. Long, Austin Ball, F. Odorici, Volker Blobel, Peter Krieger, N. K. Watson, W. Mohr, D. G. Fong, C. Lewis, D. Glenzinski, Dezso Horvath, A. M. Rossi, Stefan Schmitt, M. J. Losty, Jean-Arcady Meyer, G. A. Snow, C. P. Ward, John Allison, Stephen Lloyd, T. Tsukamoto, P. M. Watkins, Manuella Vincter, A. Posthaus, Alessandro Montanari, S. Söldner-Rembold, J. Gascon, T. J. Smith, Stan Bentvelsen, P. Gagnon, P. Mättig, R. W. Springer, W. Matthews, Shoji Asai, Norbert Wermes, Sherry Towers, T. Kawamoto, R. G. Kellogg, M. A. Thomson, E. K. U. Gross, M. Steiert, A. Sittler, Csaba Hajdu, A. Gaidot, Georges Azuelos, M. Sproston, P. Poffenberger, A. S. Turcot, Stefano Marcellini, S. Orito, E. Tsur, H. M. Bosch, F. Fiedler, M. Verzocchi, Silvia Arcelli, K. W. Bell, J. Pálinkás, M. Rosvick, J. C. Hill, J. W. Gary, Misao Sasaki, N. I. Geddes, Michael Hildreth, D. S. Koetke, M. Hapke, Marcello Mannelli, E. A. Mckigney, D. E. Hutchcroft, P. Schütz, M. Kolrep, N. L. Rodning, W. P. Lai, D. L. Rees, B. Poli, M. J. Oreglia, F. Scharf, German Martinez, J. M. Roney, H. M. Fischer, J. R. Carter, G. N. Patrick, S. A. Robins, Stefan Kluth, P. O. Estabrooks, Shlomit Tarem, A. I. McNab, J. Goldberg, B. Nellen, H. G. Evans, S. W. O'Neale, M. J. Goodrick, I. Cohen, Gunter Wolf, K. Ackerstaff, K. J. Anderson, C. Y. Chang, P. Taras, Michael Kobel, Julie Kirk, K. Stephens, V. Gibson, T. R. Junk, I. Trigger, D. R. Ward, T. Kress, U. Ruppel, M. R. Ingram, S. Robertson, Gregor Herten, B. Wilkens, P. S. Wells, J. E. Pilcher, N. J. Oldershaw, Terry Richard Wyatt, J. E. Bloomer, G. W. Wilson, M. Hauschild, S. A. Wotton, C. Markus, G. T. Jones, E. H. Vokurka, M. Fanti, D. M. Strom, M. Boutemeur, F. S. Merritt, Robert McPherson, R. Rylko, Mathieu Doucet, R. D. Heuer, J. Bechtluft, J. A. McKenna, Fabrizio Fabbri, M. Bobinski, J. A. Wilson, A. Macpherson, R. Bartoldus, P. Scharff-Hansen, R. Van Kooten, Richard Keeler, H. O. Ogren, Christoph Geich-Gimbel, D. Lazic, J. E. Conboy, A. Fürtjes, R. Howard, A. M. Smith, J. S. White, J. Grunhaus, G. Vasseur, F. Wäckerle, Andris Skuja, D. M. Gingrich, Sachio Komamiya, S. Petzold, Theodoros Geralis, E. Ros, Tetsuro Mashimo, P. Berlich, T. P. Kokott, K. Nagai, D. R. Rust, W. Gorn, M. F. Turner-Watson, M. Morii, Peter R Hobson, D. Zer-Zion, P. Routenburg, A. M. Lee, and E. von Törne
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Quark ,Physics ,Density matrix ,Particle physics ,Physics and Astronomy (miscellaneous) ,Meson ,Electron–positron annihilation ,Hadron ,D-STAR ,Polarization (waves) ,Helicity ,Nuclear physics ,High Energy Physics::Experiment ,Particle Physics - Experiment - Abstract
Measurements of helicity density matrix elements have been made for the φ(1020), D*± and B* vector mesons in multihadronic Z0 decays in the OPAL experiment at LEP. Results for inclusive φ produced with high energy show evidence for production preferentially in the helicity zero state, with ρ00 = 0.54 ± 0.08, compared to the value of 1/3 expected for no spin alignment. The corresponding element for the D*± has a value of 0.40 ± 0.02, also suggesting a deviation from 1/3. The B* result, with ρ00 = 0.36 ± 0.09, is consistent with no spin alignment. Off-diagonal elements have been measured for the f and D* mesons; for the D* the element Re ρ1−1 is non-zero, indicating non-independent fragmentation of the primary quarks.
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- 1997
- Full Text
- View/download PDF
47. A measurement of |Vcb| using decays
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A. I. McNab, A. S. Turcot, J. Goldberg, F. Fiedler, S. Yamashita, B. Nellen, P. Igo-Kemenes, Gideon Bella, H. J. Burckhart, K. Ishii, Jacqueline Batley, H. Jeremie, R. E. Hughes-Jones, M. Kolrep, K. Sachs, Shlomo Dado, M. F. Turner-Watson, M. Morii, H. G. Evans, P. Schenk, P. E.L. Clarke, M. K. Jones, Peter R Hobson, O. Schaile, M. Hapke, Achim Stahl, G. Azuelos, M. J. Goodrick, I. Cohen, J. P. Martin, S. De Jong, E. do Couto e Silva, P. Routenburg, R. Van Kooten, H. Przysiezniak, Sachio Komamiya, T. Omori, D. E. Hutchcroft, O. C. Cooke, A. N. Bell, Theodoros Geralis, E. Ros, A. T. Watson, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, G. G. Hanson, G. Giacomelli, Reda Tafirout, Klaus Kurt Desch, Giora Mikenberg, M. S. Dixit, Frans Meijers, Sven Menke, C. Y. Chang, P. G. Estabrooks, C. R. Jones, M. J. Oreglia, T. P. Kokott, A. Rooke, J. G. Layter, J. von Krogh, W. Matthews, P. S. Wells, P. Taras, Michael Kobel, Gunter Wolf, F. X. Gentit, A. J. Martin, R. K. Keeler, F. Wäckerle, Ekg Sarkisyan, P. W. Jeffreys, R. J. Hawkings, K. Ackerstaff, Terry Richard Wyatt, D. M. Gingrich, H. Mes, M. A. Thomson, J. E. Bloomer, M. Boutemeur, Ehud Duchovni, D. Rigby, R. J. Hemingway, S. Braibant, J. E.G. Edward, Julie Kirk, H. M. Fischer, T. Behnke, Guenter Duckeck, M. Jimack, P. Fath, L. A. del Pozo, C. Sbarra, U. Ruppel, M. R. Ingram, Matthias Schröder, A. D. Schaile, Gabriella Pasztor, P. Berlich, W. R. Gibson, P. M. Watkins, Paolo Giacomelli, M. Thiergen, E. K. U. Gross, J. R. Carter, J. Grunhaus, G. Yekutieli, G. N. Patrick, J. Bechtluft, A. Michelini, J. A. McKenna, Dave Charlton, B. T. Bouwens, M. Hansroul, P. Poffenberger, M. Gruwé, C. M. Hawkes, A. A. Carter, J. J. Ward, B. Stockhausen, Paul Kyberd, P. Vikas, S. B. Anderson, G. A. Snow, C. P. Ward, F. K. Loebinger, P. Szymanski, Ron Folman, Roger Jones, B. W. Kennedy, P. Jovanovic, R. M. Brown, Lorne Levinson, Otmar Biebel, Satoshi Tanaka, T. Kobayashi, C. Burgard, D. Lanske, P. Schütz, R. J. Homer, I. J. Bloodworth, R. Bartoldus, S. Söldner-Rembold, B. J. King, H. O. Ogren, P. Utzat, Christoph Geich-Gimbel, R. Bürgin, Richard Nisius, A. Gaidot, A. Skillman, Austin Ball, J. Steuerer, F. S. Merritt, D. M. Strom, T. J. McMahon, Stan Bentvelsen, Peter Krieger, M. S. Proston, Marco Cuffiani, LP Duerdoth, Stefan Kluth, C. Hartmann, D. E. Plane, Shlomit Tarem, R. K. Carnegie, M. Schumacher, Joleen Pater, E. Lefebvre, S. Robertson, P. Pfeifenschneider, Stephen Hillier, Gregor Herten, U. Müller, Silvia Arcelli, J. Letts, M. Herndon, G. M. Dallavalle, S. A. Robins, J. E. Conboy, A. Fürtjes, M. Bobinski, J. A. Wilson, R. Rylko, J. Patt, F. Odorici, Manuella Vincter, Norbert Wermes, Alessandro Montanari, Sherry Towers, N. K. Watson, B. Wilkens, K. Ametewee, T. Kawamoto, R. Giacomelli, Robert McPherson, M. Fierro, S. W. O'Neale, A. Biguzzi, Gideon Alexander, K. J. Anderson, Paolo Capiluppi, D. Lazic, S. Orito, S. R. Lautenschlager, H. A. Neal, U. Jost, R. Mir, E. A. Mckigney, M. Rosvick, Yoram Rozen, J. E. Pilcher, Mathieu Doucet, C. K. Hargrove, R. D. Heuer, M. Foucher, D. Chrisman, Tara Shears, Claire Shepherd-Themistocleous, T. Hilse, W. P. Lai, O. Runolfsson, W. Mohr, N. J. Oldershaw, Volker Blobel, Fabrizio Fabbri, P. A. Hart, T. J. Smith, A. Posthaus, K. Stephens, J. M. Roney, C. Beeston, Stephen Lloyd, M. J. Pearce, R. Howard, J. S. White, Claudio Grandi, K. Nagai, F. G. Oakham, B. Schmitt, E. L. Barberio, D. R. Rust, V. Gibson, C. Dallapiccola, D. Karlen, D. L. Rees, T. R. Junk, N. Altekamp, A. Joly, I. Trigger, R. J. Barlow, D. R. Ward, H. Lafoux, D. J. Miller, T. Kress, F. Scharf, German Martinez, A. K. Honma, Daniel Lellouch, G. W. Wilson, M. Hauschild, A. M. Lee, S. A. Wotton, Takehiko Mori, C. Markus, E. von Törne, G. T. Jones, E. H. Vokurka, V. Zacek, R. Lahmann, John Allison, D. C. Imrie, Stefan Schmitt, N. I. Geddes, Michael Hildreth, R. G. Kellogg, M. Steiert, P. Mättig, Shoji Asai, Csaba Hajdu, G. P. Siroli, Stefano Marcellini, N. L. Rodning, B. Poli, S. M. Gascon-Shotkin, Kiyotomo Kawagoe, Matthew Evans, A. M. Rossi, T. Tsukamoto, P. Scharff-Hansen, A. M. Smith, D. Axen, A. Jawahery, G. Vasseur, Peter Sherwood, Andris Skuja, Alexander Wagner, S. Petzold, J. Ludwig, G. D. Long, K. Runge, P. Bock, Tetsuro Mashimo, J. Lauber, W. Gorn, F. Strumia, S. D. Talbot, James Pinfold, D. G. Fong, C. Lewis, J. Gascon, W. J. McDonald, A. Malik, B. C. Shen, J. W. Gary, D. S. Koetke, Marcello Mannelli, P. Gagnon, A. Sittler, Siegfried Bethke, B. Nijjhar, W. G. Scott, I. Nakamura, H. M. Bosch, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, R. W. Springer, E. Tsur, M. Verzocchi, K. W. Bell, J. Pálinkás, J. C. Hill, and Misao Sasaki
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Physics ,Nuclear and High Energy Physics ,Particle physics ,Muon ,Meson ,Electron–positron annihilation ,High Energy Physics::Phenomenology ,Hadron ,Form factor (quantum field theory) ,Electron ,Rest frame ,Nuclear physics ,Recoil ,High Energy Physics::Experiment ,Nuclear Experiment - Abstract
We report a measurement of the Cabibbo-Kobayashi-Maskawa matrix element |Vcb|. From approximately 4.2 million hadronic Z0 decays recorded with the OPAL deteector, a sample is selected containing 1251 ± 125 B 0 → D ∗+ l − ν l candidates, where l is either an electron or a muon. Using Heavy Quark Effective Theory calculations for the decay form factor at zero recoil of the D∗+ meson in the B 0 rest frame, we derive |Vcb| = [36.0 ± 2.1 (stat) ± 2.4 (syst) ± 1.2 (theory)] × 10−3.
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- 1997
- Full Text
- View/download PDF
48. An improved measurement of $R_b$ using a double tagging method
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S. Yamashita, P. Igo-Kemenes, Richard Keeler, D. M. Strom, R. Howard, R. Rylko, K. Ishii, H. Jeremie, R. E. Hughes-Jones, C. Dallapiccola, Takehiko Mori, M. Hapke, H. Mes, I. P. Duerdoth, P. S. Wells, A. Biguzzi, Terry Richard Wyatt, J. E. Bloomer, V. Zacek, D. E. Hutchcroft, P. Fath, O. Schaile, Silvia Arcelli, Claire Shepherd-Themistocleous, E. do Couto e Silva, Dave Charlton, B. Stockhausen, Paul Kyberd, F. K. Loebinger, K. Sachs, Shlomo Dado, Robert McPherson, N. Altekamp, J. Steuerer, Sven Menke, R. Bürgin, Mathieu Doucet, E. A. Mckigney, Joleen Pater, Stefan Schmitt, R. D. Heuer, R. J. Barlow, A. S. Turcot, M. J. Oreglia, R. Giacomelli, T. J. Smith, Stefan Kluth, Fabrizio Fabbri, W. P. Lai, F. Fiedler, Shlomit Tarem, Giora Mikenberg, D. J. Miller, T. Behnke, P. Mättig, Shoji Asai, J. Grunhaus, J. M. Roney, K. Nagai, I. J. Bloodworth, S. Braibant, John Allison, A. D. Schaile, T. Kawamoto, Gabriella Pasztor, Gideon Bella, D. R. Rust, Kiyotomo Kawagoe, H. J. Burckhart, P. Gagnon, M. Schumacher, E. Lefebvre, M. Gruwé, Andris Skuja, M. Kolrep, Jacqueline Batley, J. R. Carter, G. N. Patrick, S. Petzold, P. Schenk, C. M. Hawkes, K. Ackerstaff, G. D. Long, K. Stephens, R. G. Kellogg, Yoram Rozen, M. Steiert, F. Odorici, G. A. Snow, C. P. Ward, Tetsuro Mashimo, Otmar Biebel, Csaba Hajdu, T. Omori, A. Sittler, P. G. Estabrooks, A. M. Lee, Richard Nisius, P. Poffenberger, Stefano Marcellini, M. Foucher, S. B. Anderson, S. Söldner-Rembold, P. Szymanski, E. von Törne, S. Robertson, V. Gibson, P. M. Watkins, H. M. Bosch, C. R. Jones, Marco Cuffiani, D. Karlen, Gregor Herten, W. Gorn, D. Rigby, R. J. Hemingway, A. Joly, G. W. Wilson, J. Letts, Stan Bentvelsen, U. Müller, Norbert Wermes, T. R. Junk, A. J. Martin, Sherry Towers, A. I. McNab, P. Schütz, J. Goldberg, D. Axen, I. Trigger, R. Van Kooten, A. Jawahery, Hans-Christian Schultz-Coulon, B. Nellen, Randall Sobie, Michael Schulz, G. D. Lafferty, M. F. Turner-Watson, S. Orito, B. Wilkens, D. R. Ward, T. Kress, M. Morii, B. W. Kennedy, James Pinfold, M. Rosvick, Achim Stahl, Peter R Hobson, P. Jovanovic, U. Ruppel, Peter Sherwood, R. Lahmann, M. R. Ingram, D. G. Fong, C. Lewis, P. Routenburg, Alexander Wagner, H. G. Evans, M. J. Goodrick, J. Gascon, C. K. Hargrove, Guenter Duckeck, Sachio Komamiya, Theodoros Geralis, E. Ros, J. E. Pilcher, Austin Ball, J. Ludwig, K. Runge, I. Cohen, P. Bock, G. P. Siroli, Matthias Schröder, N. I. Geddes, J. Lauber, N. J. Oldershaw, Peter Krieger, Michael Hildreth, M. Thiergen, H. Lafoux, T. P. Kokott, J. W. Gary, D. S. Koetke, E. Gross, Marcello Mannelli, D. Lellouch, N. L. Rodning, F. Strumia, S. D. Talbot, F. Wäckerle, B. Poli, Manuella Vincter, D. M. Gingrich, P. Scharff-Hansen, Alessandro Montanari, Tara Shears, P. A. Hart, A. M. Smith, S. M. Gascon-Shotkin, U. Jost, P. Berlich, R. Mir, G. Vasseur, M. J. Pearce, Matthew Evans, A. M. Rossi, M. Hauschild, T. Tsukamoto, Paolo Giacomelli, S. W. O'Neale, M. Hansroul, K. J. Anderson, S. A. Wotton, C. Markus, H. M. Fischer, G. T. Jones, E. H. Vokurka, C. Y. Chang, F. G. Oakham, B. Schmitt, S. A. Robins, C. Burgard, E. L. Barberio, R. J. Homer, P. Taras, Michael Kobel, P. Pfeifenschneider, Julie Kirk, J. Patt, F. S. Merritt, J. Bechtluft, J. A. McKenna, R. Bartoldus, H. O. Ogren, Christoph Geich-Gimbel, J. E. Conboy, N. K. Watson, F. X. Gentit, A. Fürtjes, W. Mohr, W. J. McDonald, B. C. Shen, Siegfried Bethke, A. K. Honma, B. Nijjhar, A. Posthaus, W. G. Scott, I. Nakamura, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, R. W. Springer, D. L. Rees, Georges Azuelos, E. Tsur, M. Verzocchi, K. W. Bell, J. Pálinkás, J. C. Hill, Misao Sasaki, F. Scharf, German Martinez, W. Matthews, M. A. Thomson, A. Gaidot, M. Sproston, C. Sbarra, G. Yekutieli, A. A. Carter, Ron Folman, Roger Jones, B. J. King, P. Utzat, T. J. McMahon, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, D. Lazic, O. C. Cooke, J. von Krogh, R. J. Hawkings, L. A. del Pozo, Ehud Duchovni, M. Jimack, A. Michelini, D. C. Imrie, Satoshi Tanaka, J. S. White, M. Boutemeur, T. Kobayashi, M. Fierro, J. E.G. Edwards, S. R. Lautenschlager, H. A. Neal, T. Hilse, O. Runolfsson, D. Chrisman, Volker Blobel, C. Beeston, Claudio Grandi, Stephen Lloyd, Ekg Sarkisyan, P. W. Jeffreys, Robert M Brown, K. Ametewee, Gideon Alexander, Paolo Capiluppi, J. J. Ward, P. Vikas, D. Lanske, W. R. Gibson, B. T. Bouwens, Lorne Levinson, A. Skillman, Abish Malik, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, Alan Watson, G. G. Hanson, Reda Tafirout, Klaus Kurt Desch, G. Wolf, G. Giacomelli, M. S. Dixit, Frans Meijers, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, H. Przysiezniak, A. N. Bell, A. Rooke, and J. G. Layter
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Nuclear physics ,Physics ,Top quark ,Particle physics ,Physics and Astronomy (miscellaneous) ,Meson ,Bottom quark ,Particle Physics - Experiment - Published
- 1997
- Full Text
- View/download PDF
49. Measurement of the triple gauge boson coupling αW from W+W− production in e+e− collisions at =161GeV
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S. A. Robins, J. R. Carter, Michael Hildreth, R. Bartoldus, N. L. Rodning, B. Poli, K. Nagai, N. K. Watson, Otmar Biebel, Shigenori Tanaka, S. M. Gascon-Shotkin, U. Müller, P. Igo-Kemenes, S. R. Lautenschlager, H. A. Neal, D. R. Rust, Matthew Evans, A. M. Rossi, T. Tsukamoto, H. O. Ogren, Christoph Geich-Gimbel, A. J. Martin, K. Ishii, H. Jeremie, T. Hilse, R. E. Hughes-Jones, M. Schumacher, E. Lefebvre, T. Behnke, O. C. Cooke, V. Gibson, A. Biguzzi, O. Runolfsson, Gideon Bella, A. M. Lee, H. J. Burckhart, E. von Törne, Jacqueline Batley, J. Letts, James Pinfold, W. Matthews, U. Ruppel, M. R. Ingram, D. G. Fong, C. Lewis, O. Schaile, F. Odorici, E. do Couto e Silva, S. Robertson, S. L. Lloyd, P. Schütz, P. Gagnon, A. Rooke, J. G. Layter, J. E. Conboy, A. Fürtjes, Gregor Herten, J. Allison, C. K. Hargrove, C. Hartmann, K. Ametewee, J. Gascon, D. E. Plane, A. Macchiolo, Sven Menke, Matthias Schröder, A. Sittler, B. Wilkens, T. Omori, Gideon Alexander, M. Sasaki, J. Palinkas, Norbert Wermes, Sherry Towers, Paolo Capiluppi, M. A. Thomson, Claudio Grandi, M. Thiergen, K. Sachs, M. Boutemeur, F. S. Merritt, T. Kawamoto, V. Zacek, R. Van Kooten, J. A. McKenna, Stephen Hillier, J. E. Pilcher, Shlomo Dado, C. R. Jones, G. M. Dallavalle, Ekg Sarkisyan, Richard Nisius, P. W. Jeffreys, J. Bechtluft, S. Orito, H. M. Bosch, M. Rosvick, S. W. O'Neale, J. von Krogh, D. S. Koetke, G. W. Wilson, T. Kobayashi, Marcello Mannelli, G. G. Hanson, H. Mes, M. Hauschild, R. G. Kellogg, M. Steiert, I. P. Duerdoth, R. W.L. Jones, S. A. Wotton, Marco Cuffiani, P. Fath, D. Chrisman, G. D. Long, E. K. U. Gross, Kiyotomo Kawagoe, C. Markus, D. M. Strom, C.J. Beeston, Csaba Hajdu, G. Giacomelli, J. Lauber, Volker Blobel, M. Hapke, Dave Charlton, K. J. Anderson, T. G. Shears, Stefano Marcellini, P. Scharff-Hansen, G. T. Jones, E. H. Vokurka, P. A. Hart, G. Mikenberg, T. J. Smith, N. J. Oldershaw, B. Nijjhar, M. J. Pearce, F. Wäckerle, Joleen Pater, M. Sproston, Claire Shepherd-Themistocleous, K. Stephens, L. A. del Pozo, C. Y. Chang, D. M. Gingrich, B. Stockhausen, Paul Kyberd, F. K. Loebinger, A. M. Smith, M. S. Dixit, Frans Meijers, R. Bürgin, M. J. Oreglia, W. R. Gibson, P. Taras, Michael Kobel, J. Steuerer, J. J. Ward, S. D. Talbot, Ehud Duchovni, R. Rylko, P. E.L. Clarke, M. K. Jones, P. Vikas, S. Braibant, A. D. Schaile, A. A. Faust, B. T. Bouwens, M. Jimack, P. Berlich, P. Poffenberger, M. Fanti, Andris Skuja, J. P. Martin, Gabriella Pasztor, R. Giacomelli, R. Lahmann, Julie Kirk, D. Lanske, A. Michelini, Gunter Wolf, K. Ackerstaff, Satoru Yamashita, S. Petzold, D. Eatough, S. De Jong, G. Yekutieli, Tetsuro Mashimo, G. N. Patrick, D. C. Imrie, R. M. Brown, Lorne Levinson, T. R. Junk, H. Przysiezniak, G. A. Snow, C. P. Ward, A. A. Carter, Ron Folman, Robert McPherson, G. P. Siroli, A. N. Bell, I. Trigger, A. Skillman, A. Joly, Mathieu Doucet, S. Söldner-Rembold, W. Gorn, S. D. Bird, R. D. Heuer, N. I. Geddes, P. Schenk, C. Sbarra, P. S. Wells, Fabrizio Fabbri, D. R. Ward, T. Kress, D. L. Rees, P. Utzat, A. T. Watson, Reda Tafirout, Klaus Kurt Desch, J. E. Bloomer, F. Scharf, German Martinez, D. Axen, A. I. McNab, A. Macpherson, J. Goldberg, A. Jawahery, T. R. Wyatt, T. J. McMahon, J. M. Roney, R. J. Sobie, B. Nellen, R. K. Carnegie, M. Herndon, R. Howard, M. Bobinski, R. J. Barlow, J. A. Wilson, J. S. White, W. Mohr, Peter Sherwood, A. Posthaus, D. Lazic, Alexander Wagner, M. Fierro, J. E.G. Edwards, J. Ludwig, K. Runge, P. Bock, H. G. Evans, M. J. Goodrick, I. Cohen, Stefan Kluth, Shlomit Tarem, R. W. Springer, Achim Stahl, Daniel Lellouch, Paolo Giacomelli, M. Hansroul, C. Burgard, Takehiko Mori, R. J. Homer, Georges Azuelos, E. Tsur, C. M. Hawkes, P. Pfeifenschneider, J. Patt, M. Verzocchi, K. W. Bell, J. C. Hill, B. C. Shen, Siegfried Bethke, A. K. Honma, W. G. Scott, I. Nakamura, J. W. Gary, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, Sachio Komamiya, Stefan Schmitt, Theodoros Geralis, M. Gruwe, E. Ros, U. Jost, R. Mir, T. P. Kokott, R. Hawkings, W.J. McDonald, P. Mättig, Shoji Asai, J. Grunhaus, I. J. Bloodworth, S. B. Anderson, P. Szymanski, Stan Bentvelsen, F. G. Oakham, Hans-Christian Schultz-Coulon, B. Schmitt, E. L. Barberio, Michael Schulz, Yoram Rozen, G. Duckeck, M. Foucher, M. F. Turner-Watson, M. Morii, Peter R Hobson, D. Zer-Zion, P. Routenburg, D. Karlen, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, A. S. Turcot, F. Fiedler, Austin Ball, Peter Krieger, Manuella Vincter, Alessandro Montanari, M. Kolrep, D. E. Hutchcroft, C. Dallapiccola, N. Altekamp, D. J. Miller, P. G. Estabrooks, R. K. Keeler, P. M. Watkins, Silvia Arcelli, E. A. Mckigney, W. P. Lai, G. D. Lafferty, and H. M. Fischer
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Semileptonic decay ,Coupling ,Physics ,Nuclear and High Energy Physics ,Particle physics ,Gauge boson ,Luminosity (scattering theory) ,Electron–positron annihilation ,law.invention ,Standard Model ,Nuclear physics ,Coupling parameter ,law ,High Energy Physics::Experiment ,Collider - Abstract
This letter describes a measurement of one of the anomalous triple gauge boson couplings using the first data recorded by the OPAL detector at LEP2. A total of 28 W-pair candidates have been selected for an integrated luminosity of 9.89+/-0.06 pb(-1) recorded at a centre-of-mass energy of 161 GeV. We use these data to place constraints upon the coupling parameter alpha(W phi). We analyse the predicted variation of the total cross-section for all observed channels and the distribution of kinematic variables in the semileptonic decay channels. We measure alpha(W phi) to be -0.61(-0.61)(+0.73)+/-0.35, which is consistent with the Standard Model expectation of zero. (C) 1997 Published by Elsevier Science B.V.
- Published
- 1997
- Full Text
- View/download PDF
50. Search for charged scalar leptons using the OPAL detector at GeV
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D. Rigby, R. J. Hemingway, V Zacek, B. W. Kennedy, R. Bartoldus, R. Lahmann, D. C. Imrie, G. P. Siroli, John Allison, P. Jovanovic, Austin Ball, J. Grunhaus, Christoph Geich-Gimbel, Peter Krieger, Manuella Vincter, Alessandro Montanari, D. Axen, A. Jawahery, R. G. Kellogg, M. Steiert, Gunter Wolf, Tara Shears, A. Biguzzi, K. Ackerstaff, Peter Sherwood, Alexander Wagner, Csaba Hajdu, K. Sachs, Shlomo Dado, I. J. Bloodworth, J. E. Conboy, A. Fürtjes, J. Ludwig, Claire Shepherd-Themistocleous, H.O Ogren, Stefano Marcellini, S. Robertson, K. Runge, P. Bock, Gregor Herten, Yoram Rozen, M. Foucher, P. A. Hart, Gideon Bella, M. J. Pearce, B. Wilkens, Giora Mikenberg, D. Karlen, H. J. Burckhart, Jacqueline Batley, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, T. Behnke, Daniel Lellouch, S. Braibant, A. D. Schaile, J. E. Pilcher, T. P. Kokott, G. Azuelos, Takehiko Mori, C. Sbarra, T. Omori, Gabriella Pasztor, R. W. Springer, M. Gruwé, C. M. Hawkes, G. A. Snow, C. P. Ward, G. Yekutieli, G. G. Hanson, C. R. Jones, U. Müller, S. Söldner-Rembold, P. Gagnon, Richard Nisius, A. A. Carter, Ron Folman, Roger Jones, A. Sittler, G. Giacomelli, C. Dallapiccola, Stefan Schmitt, A. I. McNab, J. Goldberg, Silvia Arcelli, Marco Cuffiani, H. M. Bosch, B. Nellen, B. J. King, M. Boutemeur, F. S. Merritt, Reda Tafirout, Klaus Kurt Desch, E. Tsur, M. S. Dixit, A. J. Martin, S. W. O'Neale, P. Utzat, Frans Meijers, Dave Charlton, M. Verzocchi, A. S. Turcot, F. Fiedler, J. Lauber, K. J. Anderson, P. Mättig, S Anderson, M. F. Turner-Watson, K. W. Bell, M. Morii, J. Pálinkás, A. Rooke, Peter R Hobson, J. G. Layter, Shoji Asai, P. Routenburg, R. Bürgin, N. Altekamp, F. Strumia, G. W. Wilson, E. A. Mckigney, S. D. Talbot, O. C. Cooke, M. Hauschild, J. C. Hill, S. A. Wotton, P. Poffenberger, W. R. Gibson, Misao Sasaki, H. G. Evans, J. Bechtluft, R. J. Barlow, W. P. Lai, J. A. McKenna, M. J. Goodrick, P. E.L. Clarke, D. J. Miller, C. Markus, M. K. Jones, P. Schütz, B. T. Bouwens, J. P. Martin, I. Cohen, M. Kolrep, S. De Jong, G. T. Jones, E. H. Vokurka, R. M. Brown, Lorne Levinson, A. Joly, J. M. Roney, J. von Krogh, C. K. Hargrove, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, H. Przysiezniak, N. J. Oldershaw, C. Y. Chang, A. N. Bell, M. Hapke, P. Schenk, Paolo Giacomelli, D. E. Hutchcroft, A. Skillman, P. Taras, Michael Kobel, M. Hansroul, B. Stockhausen, Paul Kyberd, F. K. Loebinger, C. Hartmann, D. E. Plane, P. S. Wells, Stephen Hillier, Julie Kirk, J. Steuerer, Joleen Pater, R. J. Hawkings, Guenter Duckeck, C. Burgard, W. J. McDonald, G. M. Dallavalle, B. C. Shen, Terry Richard Wyatt, M. J. Oreglia, R. Giacomelli, L. A. del Pozo, R. J. Homer, Siegfried Bethke, A. K. Honma, B. Nijjhar, W. G. Scott, J. E. Bloomer, I. Nakamura, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, D. Glenzinski, Dezso Horvath, M. J. Losty, N. I. Geddes, Michael Hildreth, Jean-Arcady Meyer, U. Jost, R. Mir, Stefan Kluth, J. R. Carter, N. L. Rodning, Shlomit Tarem, B. Poli, G. N. Patrick, W. Gorn, P. Szymanski, Matthias Schröder, F. G. Oakham, B. Schmitt, Otmar Biebel, M. Thiergen, E. L. Barberio, S. M. Gascon-Shotkin, Stan Bentvelsen, P. Pfeifenschneider, R. Howard, J. S. White, J. Patt, Matthew Evans, A. M. Rossi, T. Tsukamoto, J. Letts, H. M. Fischer, D. M. Strom, Norbert Wermes, Sherry Towers, T. Kawamoto, P. Scharff-Hansen, R. Rylko, S. A. Robins, S. Orito, M. Rosvick, A. M. Smith, Achim Stahl, James Pinfold, D. G. Fong, C. Lewis, J. Gascon, J. W. Gary, D. S. Koetke, Marcello Mannelli, Ekg Sarkisyan, P. W. Jeffreys, J. J. Ward, P. Vikas, D. Lanske, S. R. Lautenschlager, H. A. Neal, T. Hilse, T. J. McMahon, O. Runolfsson, R. K. Carnegie, M. Herndon, C. Beeston, U. Ruppel, Claudio Grandi, M. Bobinski, J. A. Wilson, M. R. Ingram, D. Lazic, M. Fierro, J. E.G. Edwards, T. J. Smith, K. Stephens, V. Gibson, T. R. Junk, I. Trigger, D. R. Ward, T. Kress, D. Chrisman, Volker Blobel, Stephen Lloyd, S. Yamashita, P. Igo-Kemenes, Ehud Duchovni, K. Ishii, H. Jeremie, M. Jimack, A. Michelini, R. E. Hughes-Jones, O. Schaile, E. do Couto e Silva, Satoshi Tanaka, T. Kobayashi, Sven Menke, K. Ametewee, Gideon Alexander, Paolo Capiluppi, P. G. Estabrooks, R. K. Keeler, P. M. Watkins, Kiyotomo Kawagoe, D. L. Rees, F. Scharf, German Martinez, N. K. Watson, W. Mohr, A. Posthaus, H. Mes, I. P. Duerdoth, P. Fath, R. Van Kooten, W. Matthews, M. A. Thomson, E. K. U. Gross, M. Sproston, F. Wäckerle, D. M. Gingrich, P. Berlich, M. Schumacher, E. Lefebvre, F. Odorici, K. Nagai, D. R. Rust, A. M. Lee, E. von Törne, Robert McPherson, Mathieu Doucet, R. D. Heuer, and Fabrizio Fabbri
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Physics ,Nuclear and High Energy Physics ,Particle physics ,Missing energy ,Muon ,High Energy Physics::Phenomenology ,Detector ,Scalar (physics) ,Electron ,Nuclear physics ,Selectron tube ,High Energy Physics::Experiment ,Minimal Supersymmetric Standard Model ,Lepton - Abstract
A search for pair-produced scalar electron, muon and tau leptons has been performed using a data sample corresponding to an integrated luminosity of 10.1 pb−1 at a centre-of-mass energy of s =161 GeV collected with the OPAL detector at LEP. Such events would yield an acoplanar pair of leptons with significant missing energy in the final state. No excess of acoplanar lepton pair events has been observed in the data. Limits are presented on the production cross-sections of charged scalar leptons. Exclusion regions are also presented in the framework of the Minimal Supersymmetric Standard Model. A 95% C.L. lower limit on the right-handed selectron mass of 71.5 GeV is obtained for tan β ≥ 1.5, |μ| ≥ 200 GeV and m χ 1 0 = 12.0 GeV . A 95% C.L. lower limit on the right-handed smuon mass of 51.0 GeV is obtained for m χ 1 0 = 12.0 GeV , independent of tan β and μ.
- Published
- 1997
- Full Text
- View/download PDF
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