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Instantaneous Bethe-Salpeter Equation and Its Analog： Breit-like Equation

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Communications in Theoretical Physics 2005年第4X期44卷 646-650页

作者： CHANG Chao-hsi LCCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China Institute of Theoretical Physics the Chinese Academy of Sciences P.O. Box 2735 Beijing 100080 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

We take the （μ^±e^-＋） system as an example, but restrict ourselves to highlight the states with quantum number J^P = 0^-, to explore the different contents of the instantaneous Bethe-Salpeter （BS） equation and its analog, the relativistic version of Breit equation, by solving them exactly. The results show that the two equations are not equivalent, although they are analogous. Furthermore, since the Breit equation contains extra un-physical solutions, so we point out that it should be abandoned if one wishes to have an accurate description of the bound states for the instantaneous interacting binding systems.

关键词： instantaneous BS equation Breit equation exact solutions

A New Type of Accessible Environmental Influences on Neutrino Oscillation

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Communications in Theoretical Physics 2001年第5期35卷 557-562页

作者： CHANGChao－hsi DONGHUi－Shi 等 InstituteofTheoreticalPhysics AcademiaSinicaP.O.Box2735Beijing100080China DepartmentofPhysics NankaiUniversityTianjin300071China

Considering a new type of environment influences, we use a two-energy-level quantum system to investigate neutrino oscillations in medium. Besides the matter effects derived by Wolfenstein, there may exist extra terms due to a unitary evolution of the system between pure and mixed states, so the evolution equation is modified obviously. We show that the extra terms may play some role and induce observable effects in solar neutrino problem, especially, in the long baseline neutrino oscillation experiments which are under serious consideration recently, if the parameters fall into a suitable region.

关键词： neutrino oscillation pure and mixed states extra medium effects

A proposal on complementary determination of the effective electro-weak mixing angles via doubly heavy-flavored hadron production at a super Z-factory

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Science China(Physics,Mechanics & Astronomy) 2020年第8期63卷 61-70页

作者： Xu-Chang Zheng Chao-hsi Chang Tai-Fu Feng Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China China Center of Advanced Science and Technology(CCAST)(World Laboratory) Beijing 100190China Department of Physics Hebei UniversityBaoding 071002China

To test the standard model(SM)precisely and to look for the clues deviating from SM,a proposal for determining the effective electro-weak mixing angles sin2θefff(particularly f=lept,c,b)is *** is via observing the asymmetries(the forward-backward one AFB,the left-right one ALR and the combined left-right forward-backward one ALRFB)of the doubly heavy-flavored hadrons in the production at a super Z-factory(an e+e-collider designed with a luminosity as high as possible for modernday techniques runs around the center-of-mass energy s1/2=mZ).To see the sensitivity,uncertainties as well as the event accumulation precisely,the observables for describing the asymmetries of the produced hadrons are computed numerically with varying effective mixing angles,and based on the result analyses,it is concluded that the proposal may offer an independent complement determination of the effective mixing angles.

关键词： electro-weak mixing angle production of doubly heavy-flavored hadron asymmetries super Z-factory

Spectrum of Binding System for Heavy Quark（Q） with an Anti—sbottom（b） or for a Sbottom and Anti—sbottom Pair

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Communications in Theoretical Physics 2003年第2期39卷 197-204页

作者： CHANGChao－hsi CUIJian－Ying 等 CCAST（WorldLaboratory） P.O.Box8730Beijing100080China；InstituteofTheorticalPhysicstheChineseAcademyofSciencesP.O.Box2735Beijing100080China DepartmentofPhysics YantaiUniversity

Since long-lived light bottom squark (sbottom) and its anti-particle with a mass close to the bottomquark have not been excluded by experiments so far, so we would like to consider such a sbottom to combine with itsanti-particle to form a color singlet meson-like bound state or to combine with a common anti-quark to form a fermion-like one, or accordingly their anti-particles to form an anti-particle bound system. Namely we calculate the low-lyingspectrum of the systems specifically based on QCD inspired potential model. To be relativistic as much as possible, westart with the framework of Bethe-Salpeter (BS) equation even for non-relativistic binding systems. Finally, we obtainthe requested spectrum by constructing general forms of the BS wave functions and solving the BS equations underinstantaneous approximation.

关键词：重夸克束缚态 BS方程标准模型

Study the Characteristics of Titanium Oxide Hydrogen Ion Sensor Using XRD and AES

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稀有金属材料与工程 2006年第A3期35卷 250-251页

作者： Jung-Chuan Chou Hung-hsi Yang Graduate School of Electronic Engineering National Yunlin University of Science and TechnologyDouliouTaiwan 640China

We study the extended gate ion sensitive structure,and deposit the titanium oxide (TiO_2) thin film on p-type (100) silicon *** device of the hydrogen ion sensing structure is TiO_2/Si-substrate,and a commercial device of the metal oxide semiconductor field effect transistor (MOSFET) is connected to the separative sensing *** sensitivity and linearity are measured under different work *** the mixed ratio of Ar/O_2 is 80 ml·min^(-1)/20 ml·min^(-1),the work pressure is 4 Pa,the sputtering power is 150 W,and the sputtering time is two hours,the better sensing properties of the sensitivity and linearity are 36.49 mV/pH and 0.99654,***,some instruments are analyzed the surface of TiO_2 membrane,such as X-ray diffraction (XRD) and Auger Electron Spectrometer (AES).The characteristics of TiO_2 thin film can be demonstrated.

关键词： titanium oxide separative sensing device sensitivity linearity X-ray diffraction auger electron spectrometer

Recent developments in neuropsychological endophenotypes for schizophrenia: Development of the MATRICS battery, liability syndromes and the near future

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Chinese Science Bulletin 2011年第32期56卷 3385-3393页

作者： STONE William S hsi xia.lu Department of Psychiatry Massachusetts Mental Health Center Division of Beth Israel Deaconess Medical Center Harvard Medical School Boston MA 02115-6092 USA MIT Medical Massachusetts Institute of Technology (MIT) Cambridge MA 02139 USA

Cognitive deficits are now recognized widely as core features of schizophrenia, and as major contributors to the clinical outcome of the disorder. They are also studied widely as 'endophenotypes', reflecting a growing consensus that schizophrenia is a broader, more multidimensional illness than the diagnostic criteria required for its formal diagnosis. This evolving view of cognition underlies its utilization in recent initiatives for intervention and assessment in schizophrenia. Two of these initiatives are reviewed in this paper. The first focuses on the development and validation of the MATRICS Cognitive Consensus Battery, a standardized battery of neuropsychological tests developed to assess the effectiveness of cognitive enhancing treatments in schizophrenia. A part of this effort includes the identification of performance-based, 'co-primary' measures of functional capacity that are related to cognition, and that are likely to show improvement at least partly as a function of improved cognition. The second initiative involves efforts to utilize neuropsychological deficits in the identification, validation and remediation of a liability syndrome for schizophrenia ('schizotaxia'). The discussion of this effort focuses on the development of a syndrome that is both measurable and meaningful clinically, and that may provide useful intervention targets. The utilization of cognition in both of these initiatives underscores its functional importance in the clinical outcome of schizophrenia. Moreover, it helps to illuminate indicators of liability for schizophrenia that might be amenable to remediation.

关键词：精神分裂症心理测验综合征电池神经稳定责任认知功能

Refinement of circular-polarization based on multilayer film structure

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 94-97页

作者： LEE Kuei-jen CHOU hsi-tseng Key Laboratory of Optical Communications and Lightwave Technologies Beijing University of Posts and Telecommunications

Circular-polarization discrimination appears in many antennas＇ applications. A compensation approach based on multilayer film structure is proposed to improve the axial ratio of the magnitude of the two perpendicular modes of the lump ports. The goal is to widen the beamwidth of radiation that has an axial ratio less than 3 dB and thus reducing the complexity at the receiver. A transfer matrix method was developed to represent the multilayer film and characterize its performance. Simulation using high frequency structure simulator shows that a crossed dipole, as an example, can achieve a beamwidth of more than 30° at the frequency of 12.45 GHz after compensation. Finally, conclusions and future work about this compensation method are presented.

关键词： crossed dipole multilayer compensation beamwidth

On Possible S-Wave Bound States for an N-↑N System Within a Constituent Quark Model

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Communications in Theoretical Physics 2005年第2期43卷 275-282页

作者： CHANGChao-hsi PANGHou-Rong InstituteofTheoreticalPhysics theChineseAcademyofSciencesP.O.Box2735Beijing100080China／／CCAST（WorldLaboratory）P.O.Box8730Beijing100080China DepartmentofPhysics SoutheastUniversityNanjing210096China

We try to apply a constituent quark model (a variety chiral constituent quark model) and the resonating group approach for the multi-quark problems to compute the effective potential between the NN- in S-wave (the quarks in the nucleons N and N-, and the two nucleons relatively as well, are in S wave) so as to see the possibility if there may be a tight bound state of six quarks as indicated by a strong enhancement at threshold of pp- in J/ψ and B decays. The effective potential which we obtain in terms of the model and approach shows if the experimental enhancement is really caused by a tight S-wave bound state of six quarks, then the quantum number of the bound state is very likely to be I = 1, JPC= 0-+.

关键词： nucleon-antinucleon effective interaction multiquark system constituentquark model

Non-spectator Contributions to Lifetime of ∧b

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Communications in Theoretical Physics 2004年第5X期42卷 723-734页

作者： CHANGChao-hsi GUOPeng LIXue-Qian WANGGuo-Li InstituteofTheoreticalPhysics AcademiaSinicaP.O.Box2735Beijing100080China DepartmentofPhysics NankaiUniversityTianjin300071China

In this work, we study the contributions of non-spectator effects to the lifetimes of Λb and B-mesons comparatively. Based on the well-established theoretical framework about the effective weak Lagrangian, we derive the formulation of the non-spectator effects at the quark level. Especially, for Λb we have considered two pictures: the three-valence-quark picture and the quark-diquark picture. In the two pictures, the interference contributions to the total width are different, in this work, we investigate the interference effects in detail. As a preliminary estimate on the lifetimes, we evaluate the hadronic matrix elements appearing in the final formulas of the lifetimes by means of a simple phenomenological model for both pictures. Our results show that the contributions of the non-spectator effects can reduce the ratio of lifetime of Λb to that of B-mesons by 5 ～ 7%. It is noted that in the quark-diquark picture the ratio can be further reduced if excited states of the diquark system are taken into account. We conclude that the measured ratio τ(Λb)/τ(B0)(≈)0.79 [The Data Group, Phys. Rev. D66 (2002) 010001] can be partly understood by the non-spectator effects, although the problem on the discrepancy between theoretical prediction and experimental measurement is not fully solved.

关键词：寿命粒子物理学重夸克效应衰退轨道