1,027 research outputs found

    Production of f0(1710)f_0(1710), f0(1500)f_0(1500), and f0(1370)f_0(1370) in J/ψJ/\psi hadronic decays

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    A coherent study of the production of f0if_0^i (i=1i=1, 2, 3 corresponding to f0(1710)f_0(1710), f0(1500)f_0(1500), and f0(1370)f_0(1370)) in J/ψ→Vf0→VPPJ/\psi\to V f_0 \to V PP is reported based on a previously proposed glueball and QQˉQ\bar{Q} nonet mixing scheme, and a factorization for the decay of J/ψ→Vf0iJ/\psi\to V f_0^i, where VV denotes the isoscalar vector mesons ϕ\phi and ω\omega, and PP denotes pseudoscalar mesons. The results show that the J/ψJ/\psi decays are very sensitive to the structure of those scalar mesons, and suggest a glueball in the 1.5−1.71.5-1.7 GeV region, in line with Lattice QCD. The presence of significant glueball mixings in the scalar wavefunctions produces peculiar patterns in the branching ratios for J/ψ→Vf0i→VPPJ/\psi\to V f_0^i\to VPP, which are in good agreement with the recently published experimental data from the BES collaboration.Comment: Version accepted by PRD; Numerical results in Tab IV and VI changed due to correction of an error in quoting an experimental datum; Conclusion is not change

    The Microsoft 2016 Conversational Speech Recognition System

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    We describe Microsoft's conversational speech recognition system, in which we combine recent developments in neural-network-based acoustic and language modeling to advance the state of the art on the Switchboard recognition task. Inspired by machine learning ensemble techniques, the system uses a range of convolutional and recurrent neural networks. I-vector modeling and lattice-free MMI training provide significant gains for all acoustic model architectures. Language model rescoring with multiple forward and backward running RNNLMs, and word posterior-based system combination provide a 20% boost. The best single system uses a ResNet architecture acoustic model with RNNLM rescoring, and achieves a word error rate of 6.9% on the NIST 2000 Switchboard task. The combined system has an error rate of 6.2%, representing an improvement over previously reported results on this benchmark task

    Tetraquark spectroscopy

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    A complete classification of tetraquark states in terms of the spin-flavor, color and spatial degrees of freedom was constructed. The permutational symmetry properties of both the spin-flavor and orbital parts of the quark-quark and antiquark-antiquark subsystems are discussed. This complete classification is general and model-independent, and is useful both for model-builders and experimentalists. The total wave functions are also explicitly constructed in the hypothesis of ideal mixing; this basis for tetraquark states will enable the eigenvalue problem to be solved for a definite dynamical model. This is also valid for diquark-antidiquark models, for which the basis is a subset of the one we have constructed. An evaluation of the tetraquark spectrum is obtained from the Iachello mass formula for normal mesons, here generalized to tetraquark systems. This mass formula is a generalizazion of the Gell-Mann Okubo mass formula, whose coefficients have been upgraded by means of the latest PDG data. The ground state tetraquark nonet was identified with f0(600)f_{0}(600), κ(800)\kappa(800), f0(980)f_{0}(980), a0(980)a_{0}(980). The mass splittings predicted by this mass formula are compared to the KLOE, Fermilab E791 and BES experimental data. The diquark-antidiquark limit was also studied.Comment: Invited talk at 11th International Conference on Meson-Nucleon Physics and the Structure of the Nucleon (MENU 2007), Julich, Germany, 10-14 Sep 2007. In the Proceedings of 11th International Conference on Meson-Nucleon Physics and the Structure of the Nucleon (MENU 2007), Julich, Germany, 10-14 Sep 2007, eConf C070910, 163 (2007

    Universal CP-nonconserving theories

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    The assumptions of the normal phenomenological weak-interaction theory are examined, and successively relaxed with a view to listing systematically all theories which are in varying degrees similar to the usual theory. A theory is found, of the current-current form, which is universal in the conventional sense, uses only V-A currents, is capable of yielding CP violation, and is consistent with all existing experimental results

    High-energy interactions and a multi-Regge-pole hypothesis

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    It is assumed that in certain well-defined kinematic regions, production amplitudes may be described as due to the exchange of a number of Regge poles, and formulas are given expressing the amplitude in terms of the permitted trajectories. Experimental tests and consequences of the hypothesis are discussed. Tests should be possible at present accelerator energies. The hypothesis leads to strong damping of production cross sections in the invariant momentum transfers, and therefore could serve as the basis for the assumptions of a previous paper

    Bounded-momentum transfer restrictions on high-energy interactions

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    A discussion is given of experimental implications of the hypothesis that production cross sections die off rapidly with an increase in any of the independent invariant momentum transfers in the process. Consequences are presented for both high-energy laboratory and cosmic-ray conditions. The results are consistent with existing evidence

    Computer aided diagnosis for cardiovascular diseases based on ECG signals : a survey

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    The interpretation of Electroencephalography (ECG) signals is difficult, because even subtle changes in the waveform can indicate a serious heart disease. Furthermore, these waveform changes might not be present all the time. As a consequence, it takes years of training for a medical practitioner to become an expert in ECG-based cardiovascular disease diagnosis. That training is a major investment in a specific skill. Even with expert ability, the signal interpretation takes time. In addition, human interpretation of ECG signals causes interoperator and intraoperator variability. ECG-based Computer-Aided Diagnosis (CAD) holds the promise of improving the diagnosis accuracy and reducing the cost. The same ECG signal will result in the same diagnosis support regardless of time and place. This paper introduces both the techniques used to realize the CAD functionality and the methods used to assess the established functionality. This survey aims to instill trust in CAD of cardiovascular diseases using ECG signals by introducing both a conceptional overview of the system and the necessary assessment method

    Production, Collection and Utilization of Very Long-Lived Heavy Charged Leptons

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    If a fourth generation of leptons exists, both the neutrino and its charged partner must be heavier than 45 GeV. We suppose that the neutrino is the heavier of the two, and that a global or discrete symmetry prohibits intergenerational mixing. In that case, non-renormalizable Planck scale interactions will induce a very small mixing; dimension five interactions will lead to a lifetime for the heavy charged lepton of O(1−100)O(1-100) years. Production of such particles is discussed, and it is shown that a few thousands can be produced and collected at a linear collider. The possible uses of these heavy leptons is also briefly discussed.Comment: 9 pages Late

    On Muddled Methods and Their Meaning

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68431/2/10.1177_048661346900100105.pd
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