21 research outputs found

    Color Confinement, Quark Pair Creation and Dynamical Chiral-Symmetry Breaking in the Dual Ginzburg-Landau Theory

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    We study the color confinement, the qq-qˉ\bar q pair creation and the dynamical chiral-symmetry breaking of nonperturbative QCD by using the dual Ginzburg-Landau theory, where QCD-monopole condensation plays an essential role on the nonperturbative dynamics in the infrared region. As a result of the dual Meissner effect, the linear static quark potential, which characterizes the quark confinement, is obtained in the long distance within the quenched approximation. We obtain a simple expression for the string tension similar to the energy per unit length of a vortex in the superconductivity physics. The dynamical effect of light quarks on the quark confining potential is investigated in terms of the infrared screening effect due to the qq-qˉ\bar q pair creation or the cut of the hadronic string. The screening length of the potential is estimated by using the Schwinger formula for the qq-qˉ\bar q pair creation. We introduce the corresponding infrared cutoff to the strong long-range correlation factor in the gluon propagator as a dynamical effect of light quarks, and obtain a compact formula of the quark potential including the screening effect in the infrared region. We investigate the dynamical chiral-symmetry breaking by using the Schwinger-Dyson equation, where the gluon propagator includes the nonperturbative effect related toComment: 37 pages, plain TeX (using `phyzzx' macro), (( 8 figures - available on request from [email protected] )

    Monopole characteristics in various Abelian gauges

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    Renormalization group (RG) smoothing is employed on the lattice to investigate and to compare the monopole structure of the SU(2) vacuum as seen in different gauges (maximally Abelian (MAG), Polyakov loop (PG) and Laplacian gauge (LG)). Physically relevant types of monopoles (LG and MAG) are distinguished by their behavior near the deconfining phase transition. For the LG, Abelian projection reproduces well the gauge independent monopole structure encoded in an auxiliary Higgs field. Density and localization properties of monopoles, their non-Abelian action and topological charge are studied. Results are presented confirming the Abelian dominance with respect to the non-perturbative static potential for all gauges considered.Comment: 36 pages, 12 figure

    Precision Analysis of the 136Xe Two-Neutrino ββ Spectrum in KamLAND-Zen and Its Impact on the Quenching of Nuclear Matrix Elements

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    We present a precision analysis of the 136Xe two-neutrino ββ electron spectrum above 0.8MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ββ rate allows us to measure the ratio of the leading and subleading 2νββ nuclear matrix elements (NMEs), ξ2ν31 = −0.26 +0.31−0.25. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ2ν31 range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ2ν31 values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ββ decay, ξ2ν31 provides new insights toward reliable neutrinoless ββ NMEs

    On Functionally Commutative Quantum Systems

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    Non-Linear Motion Characteristics of a Shallow Draft Cylindrical Barge Type Floater for a FOWT in Waves

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    A shallow draft cylindrical barge type floater with footing close to the water surface was experimentally evaluated in waves to investigate non-linear motion characteristics. The floater was designed to be used as an option for FOWT—floating offshore wind turbines. The non-linear mechanism can be promoted due to the viscous force that acts on the footing edges and the footing interaction with the free surface. In general, the observed non-linear viscous damping is modeled as a force proportional to the square of the relative velocity between the floater and the water. Therefore, the viscous damping levels is expected to increase, and the response in waves, to decrease. However, an increase in motion responses was observed for a broad range of wave periods. An attempt was made to clarify the hydrodynamic mechanism by comparing wave tank experiments, numerical calculations by CFD—computational fluid dynamics codes, and linear potential theory codes. Regular wave tests for three different wave height conditions were carried out, including free decay tests in still waters. For CFD simulations, the OpenFOAM code was selected. For potential theory simulations, the WAMIT code was chosen. As a result of the research, three points could be highlighted and discussed: first, the hydrodynamic phenomenon that contributed to the non-linear motion of the floater was identified; second, the increase and coupling of the motions response of heave and pitch motions; and finally, the phenomenon that the footing held water mass and lifted it to the water surface. The CFD calculations were able to get good qualitative results compared with the experiments and confirmed the use of CFD as a useful tool to capture the non-linear hydrodynamic phenomenon. The linear potential theory was not able to capture the phenomenon discussed herein

    Effect of biological factors on successful measurements with skeletal-muscle 1H-MRS

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    Tomonori Isobe,1 Yoshikazu Okamoto,1 Yuji Hirano,2 Hiroki Ando,3 Kenta Takada,1 Eisuke Sato,4 Kazuya Shinoda,5 Kiichi Tadano,4 Hideyuki Takei,2 Satoshi Kamizawa,1 Yutaro Mori,3 Hiroaki Suzuki1 1Faculty of Medicine, University of Tsukuba, Ibaraki, Japan; 2Department of Radiology, University of Tsukuba Hospital, Ibaraki, Japan; 3Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan; 4Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, Tokyo, Japan; 5Department of Radiology, Tsukuba Medical Center Hospital, Ibaraki, Japan Background: Our purpose in this study was to clarify whether differences in subject group attributes could affect data acquisition in proton magnetic resonance spectroscopy (1H-MRS).Methods: Subjects without diabetes mellitus (DM) were divided into two groups (group A, in their 20s; group B, 30–60 years old). Subjects with DM formed group C (30–60 years old). The numbers of subjects were 19, 27, and 22 for group A, B, and C respectively. For all subjects, 1H-MRS measurements were taken of the soleus muscle (SOL) and the anterior tibial muscle (AT). We defined the success of the measurements by the detection of intramyocellular lipids. Moreover, we also measured the full width at half maximum of the water peaks for all subjects. Results: The success rate was significantly higher for the AT (100%) than for the SOL (81.6%) (P<0.01). For the SOL, the success rate was 100% in group A, 85.2% in group B, and 77.3% in group C. There was a significant difference (P<0.05) between groups A and B, as well as between groups A and C. In all subjects, there was a significant difference (P<0.01) in the full width at half maximum (Hz) of the water peak between the AT and SOL measurements.Conclusion: We conclude that differences in the age and DM history of subjects could affect the probability of successful 1H-MRS data acquisition. Keywords: MRS, skeletal muscle, IMCL, EMCL, biological factor, FWH
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