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分类： 图书馆学、情报学 >> 情报学

虚拟现实技术近几年发展迅速，本文通过分析专利申请、专利权人、专利布局和热点技术等专利情报，为我国企业和相关科研机构进行技术研发和布局提供参考。 |

提交时间：
2017-08-24
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Energy Level Statistics of the U(5) and O(6) Symmetries in the Interacting Boson Model

Jing Shu; Ying Ran; Tao Ji; Yu-xin Liu分类： 物理学 >> 基本粒子与场物理学

We study the energy level statistics of the states in U(5) and O(6) dynamical symmetries of the interacting boson model and the high spin states with backbending in U(5) symmetry. In the calculations, the degeneracy resulting from the additional quantum number is eliminated manually. The calculated results indicate that the finite boson number N effect is prominent. When N has a value close to a realistic one, increasing the interaction strength of subgroup O(5) makes the statistics vary from Poisson-type to GOE-type and further recover to Poisson-type. |

提交时间：
2017-08-24
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Statistical Properties of E(5) and X(5) Symmetries

Jing Shu; Hong-bo Jia; Yu-xin Liu分类： 物理学 >> 基本粒子与场物理学

We study the energy level statistics of the states in E(5) and X(5) dynamical symmetries. The calculated results indicate that the statistics of E(5) symmetry is regular and follows Poisson statistics, while that of X(5) symmetry involves two maxima in the nearest neighbor level spacing distribution P(s) and the ∆3 statistics follows the GOE statistics. It provides an evidence that the X(5) symmetry is at the critical point exhibiting competing degrees of freedom |

提交时间：
2017-08-24
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Models of Baryogenesis via Spontaneous Lorentz Violation

Sean M. Carroll; Jing Shu分类： 物理学 >> 基本粒子与场物理学

In the presence of background fields that spontaneously violate Lorentz invariance, a matter-antimatter asymmetry can be generated even in thermal equilibrium. In this paper we systematically investigate models of this type, showing that either high-energy or electroweak versions of baryogenesis are possible, depending on the dynamics of the Lorentz-violating fields. In addition to the previously-studied models of spontaneous baryogenesis and quintessential baryogenesis, we identify two scenarios of interest: baryogenesis from a weak-scale pseudo-Nambu-Goldstone boson with intermediate-scale baryon-number violation, and sphaleron-induced baryogenesis driven by a constant-magnitude vector with a late-time phase transition. |

提交时间：
2017-08-24
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Baryogenesis from an Earlier Phase Transition

Jing Shu; Tim M.P. Tait; Carlos E.M. Wagner分类： 物理学 >> 基本粒子与场物理学

We explore the possibility that the observed baryon asymmetry of the universe is the result of an earlier phase transition in which an extended gauge sector breaks down into the SU(3)C × SU(2)L × U(1)Y of the Standard Model. Our prototypical example is the Topflavor model, in which there is a separate SU(2)1 for the third generation from the SU(2)2 felt by the first two generations. We show that the breakdown of SU(2)1 × SU(2)2 → SU(2)L results in lepton number being asymmetrically distributed through-out the three families, and provided the SM electroweak phase transition is not strongly first order, results in a non-zero baryon number, which for parameter choices that can be explored at the LHC, may explain the observed baryon asymmetry. |

提交时间：
2017-08-24
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分类： 物理学 >> 基本粒子与场物理学

As the surface magnetic field in niobium cavities approaches the theoretical critical field, RF losses grow sensitive to increasingly subtle features of the material and the surface. A striking example is the familiar onset of the high field Q-slope, where RF losses increase exponentially with field. A surprising feature of the high field Q-slope is its positive response to a mild baking at 100-120 鈼. But the Q-slope returns after the first 20 nm of the niobium metal surface is converted to loss-less pentoxide via anodization. The latter result suggests that the cause of the fast growing losses resides in the first 20 nm of the RF surface. Although there are several propositions, the exact mechanism for the high field Q-slope is not yet fully understood and demands further research. We are conducting surface analytic studies with optical profilometry, EBSD, XPS, Auger and SIMS to shed light on the mechanism of the high field Q-slope. We are comparing the behavior of fine-grain niobium with single crystal niobium, buffered chemical polishing (BCP) treatments with electropolishing (EP) treatments and properties before and after 110 鈼 bake. Our approach is based on identifying lossy regions, dissecting of these regions and range of analysis. |

提交时间：
2017-08-24
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Kaluza-Klein Gluons as a Diagnostic of Warped Models

Ben Lillie; Jing Shu; Tim M.P. Tait分类： 物理学 >> 基本粒子与场物理学

We study the properties of g 1 , the first excited state of the gluon in representative variants of the Randall Sundrum model with the Standard Model fields in the bulk. We find that measurements of the coupling to light quarks (from the inclusive cross-section for pp → g 1 → tt), the coupling to bottom quarks (from the rate of pp → g 1 b), as well as the overall width, can provide powerful discriminants between the models. In models with large brane kinetic terms, the g 1 resonance can even potentially be discovered decaying into dijets against the large QCD background. We also derive bounds based on existing Tevatron searches for resonant tt production and find that they require Mg 1 & 950 GeV. In addition we explore the pattern of interference between the g 1 signal and the non-resonant SM background, defining an asymmetry parameter for the invariant mass distribution. The interference probes the relative signs of the couplings of the g 1 to light quark pairs and to tt, and thus provides an indication that the top is localized on the other side of the extra dimension from the light quarks, as is typical in the RS framework. |

提交时间：
2017-08-24
点击量*131*，
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Unitarity Bounds for New Physics from Axial Coupling at LHC

Jing Shu分类： 物理学 >> 基本粒子与场物理学

If a new massive vector boson with nonzero axial couplings to fermions will be observed at LHC, then an upper limit on the scale of new physics could be derived from unitarity of S-matrix. The new physics will involve either new massive fermions, or scalars, or even a strongly coupled sector. We derive a model independent bound on the scale of new physics. If MG/g A < 3 TeV and the fermion is a top quark, the upper limit is 78 TeV. |

提交时间：
2017-08-24
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SPONTANEOUS LORENTZ VIOLATION AND BARYOGENESIS

JING SHU分类： 物理学 >> 基本粒子与场物理学

In the presence of background fields that spontaneously violate Lorentz invariance, a matter-antimatter asymmetry can be generated even in thermal equilibrium. In this paper we systematically investigate models of this type, showing that either high-energy or electroweak versions of baryogenesis are possible, depending on the dynamics of the Lorentz-violating fields. We identify two scenarios of interest: baryogenesis from a weak-scale pseudo-Nambu-Goldstone boson with intermediatescale baryon-number violation, and sphaleron-induced baryogenesis driven by a constant-magnitude vector with a late-time phase transition. |

提交时间：
2017-08-24
点击量*55*，
下载量*16*

Top Compositeness at the Tevatron and LHC

Ben Lillie; Jing Shu; Tim M.P. Tait分类： 物理学 >> 基本粒子与场物理学

We explore the possibility that the right-handed top quark is composite. We examine the consequences that compositeness would have on tt production at the Tevatron, and derive a weak constraint on the scale of compositeness of order a few hundred GeV from the tt inclusive cross section. More detailed studies of differential properties of tt production could potentially improve this limit. We find that a composite top can result in an enhancement of the tttt production rate at the LHC (of as much as 103 compared to the Standatd Model four top rate). We explore observables which allow us to extract the four top rate from the backgrounds, and show that the LHC can either discover or constrain top compositeness for wide ranges of parameter space. |

提交时间：
2017-08-24
点击量*35*，
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