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Chinese Physics C 2024年第8期48卷 104-112页

作者： Zhi-Guo He Xiao-Bo Jin Bernd A.Kniehl Rong Li Department of Physics and Electronics School of Mathematics and PhysicsBeijing University of Chemical TechnologyBeijing 100029China ii.institut für theoretische physik Universität HamburgLuruper Chaussee 14922761 HamburgGermany institut für theoretische physik Universität Regensburg93040 RegensburgGermany Center of Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China institute of Theoretical Physics Xi’an Jiaotong UniversityXi’an 710049China

Within the framework of nonrelativistic-QCD factorization,we calculate both the next-to-leading-order relativistic and QCD corrections to prompt J/ψpair production,with feed-down fromψ(2S)mesons,via photon-photon collisions at future e^(+)e^(−)colliders,including the Future Circular Lepton Collider(FCC-ee),the Circular Electron Positron Collider(CEPC),and the Compact Linear Collider(CLIC).We present total cross sections and distributions in single J/ψtransverse momentum and rapidity,as well as in J/ψpair invariant *** relativistic and QCD corrections both turn out to be large and ***,the production rates are large enough for useful experimental studies.

关键词： heavy quarkonium perturbative calculation two-photon collisions

Quantum Impurity Models with Coupled Cluster Method

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Communications in Theoretical Physics 2010年第9期54卷 509-517页

作者： Clive Emary Tobias Brandes institut für theoretische physik

We investigate the ground-state properties of the Anderson single impurity model （finite Coulomb impurity repulsion） with the Coupled Cluster Method. We consider different CCM reference states and approximation schemes and make comparison with exact Green＇s function results for the non-interacting model and with Brillouin-Wigner perturbation theory for the full interacting model. Our results show that coupled cluster techniques are well suited to quantum impurity problems.

关键词： strongly correlated electrons Anderson model coupled-cluster method quantum impurity

Uncertainty relations for general phase spaces

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Frontiers of physics 2016年第3期11卷 51-60页

作者： Reinhard F. Werner institut fiir theoretische physik Leibniz Universitiit Hannover Germany

We describe a setup for obtain!ing uncertainty relations for arbitrary pairs of observables related by a Fourier transform. The physical examples discussed here are the standard position and momentum, number and angle, finite qudit systems, and strings of qubits for quantum information applications. The uncertainty relations allow for an arbitrary choice of metric for the outcome distance, and the choice of an exponent distinguishing, e.g., absolute and root mean square deviations. The emphasis of this article is on developing a unified treatment, in which one observable takes on values in an arbitrary locally compact Abelian group and the other in the dual group. In all cases, the phase space symmetry implies the eciuality of measurement and preparation uncertainty bounds. There is also a straightforward method for determining the optimal bounds.

关键词： uncertainty relations phase space measurement uncertainty

Transport coefficients of a massive pion gas

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Chinese Physics C 2010年第9期34卷 1453-1455页

作者： D.Fernández-Fraile A.Gómez Nicola institut für theoretische physik Johann Wolfgang Goethe-Universitt Departamento de Física Teórica ii Universidad Complutense

We review our main results concerning the transport coefficients of a light meson gas,in particular we focus on the case of a massive pion *** order results according to the chiral power-counting are presented for the DC electrical conductivity,thermal conductivity,shear viscosity,and bulk *** also comment on the possible correlation between the bulk viscosity and the trace anomaly in QCD,as well as the relation between unitarity and a minimum of the quotient η/s near the phase transition.

关键词： transport coefficients heavy-ion collisions Chiral Perturbation Theory

Nuclear Dynamics at the Particle Threshold

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原子核物理评论 2015年第2期32卷 129-136页

作者： Nadia Tsoneva Horst Lenske institut fur theoretische physik Universitat Gieβen

Recently, new low-energy modes of excitation called pygmy resonances have been *** distinct feature is the close connection to nuclear skin oscillations. A successful description of the pygmy resonances could be achieved in a microscopic theoretical approach which incorporates the density functional theory and QRPA formalism extended with multi-phonon degrees of freedom. The latter is found of crucial importance for the understanding of the fine structure of nuclear electric and magnetic excitations at low energies. Corresponding microscopic multi-phonon response functions are implemented in the studies of s-process of nucleosynthesis.

关键词： microscopic nuclear model density functional theory extended quasiparticle-random-phase-approximation nucleon-capture reactions stellar nucleosynthesis

Formation of Superheavy Nuclei in Massive Fusion Reactions

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原子核物理评论 2009年第S1期26卷 168-174页

作者： Scheid Werner institut fr theoretische physik der Universitt

Within the concept of the dinuclear system(DNS),by incorporating the coupling of the relative motion to the nucleon transfer process,a dynamical model is proposed for describing the formation of superheavy residue nucleus in massive fusion reactions,in which the capture of two heavy colliding nuclei,the formation of compound nucleus and the de-excitation process are calculated using empirical coupled channel model,solving master equation numerically and statistical theory,respectively. By using the DNS model,the evaporation-residue excitation functions in the 48Ca induced fusion reactions and in the cold fusion reactions are investigated systematically and compared with available experimental data. Optimal evaporation channels and combinations as well as the corresponding excitation energies are proposed. The possible factors that influencing the isotopic dependence of the production cross sections are analyzed. The formation of the superheavy nuclei based on the isotopes U with different projectiles are also investigated.

关键词： DNS model massive fusion reaction evaporation-residue excitation function

A Coupled Variable Coefficient Modified KdV Equation Arising from a Two-Layer Fluid System

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Communications in Theoretical Physics 2007年第12期48卷 961-970页

作者： GAO Yuan~1 and TANG Xiao-Yan~(1,2)~1 Department of Physics,Shanghai Jiao Tong University,Shanghai 200240,China~2 institut Für theoretische physik IV,Fakultt für physik und Astronomie,Ruhr-Universitt Bochum,D-44870 Bochum,Germany Department of Physics Shanghai Jiao Tong University institut Fur theoretische physik IV Fakultat fur Physik und Astronomie Ruhr-Universitat Bochum

A quite general coupled variable coefficient modified KdV (VCmKdV) equation in a two-layer fluid systemis derived by means of the reductive perturbation *** use of the CK's direct method,some similarityreductions of the coupled VCmKdV equation are obtained and their corresponding group explanations are *** exact solutions of the coupled equations are also presented.

关键词： coupled variable coefficient mKdV equation two-layer fluid similarity solution periodic waves

Production of the X(4014)as the Spin-2 Partner of X(3872)in e^(+)e^(-)Collisions

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Chinese Physics Letters 2024年第3期41卷 30-36页

作者： Pan-Pan Shi Vadim Baru Feng-Kun Guo Christoph Hanhart Alexey Nefediev CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Departamento de F′ısica Te′orica and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigaci′on de PaternaAptdo.2208546071 ValenciaSpain institut fur theoretische physik ii Ruhr-Universitat BochumD-44780 BochumGermany Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China institute for Advanced Simulation Institut fur Kernphysik and Julich Center for Hadron PhysicsForschungszentrum JulichD-52425 JulichGermany Jozef Stefan institute Jamova 391000LjubljanaSlovenia CeFEMA Center of Physics and Engineering of Advanced MaterialsInstituto Superior T′ecnicoAvenida Rovisco Pais 11049-001 LisboaPortugal

In 2021,the Belle collaboration reported the first observation of a new structure in theψ(2S)γfinal state produced in the two-photon fusion *** the hadronic molecule picture,this new structure can be associatedwith the shallow isoscalar D*D* bound state and as such is an excellent candidate for the spin-2 partner of the X(3872)with the quantum numbers J^(PC)=2^(++)conventionally named X_(2).

关键词： process X(3872) Collisions

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Hadron molecules

Chinese Physics C 2010年第9期34卷 1185-1190页

作者： Thomas Gutsche Tanja Branz Amand Faessler Ian Woo Lee Valery E.Lyubovitskij institut für theoretische physik Universitt TübingenKepler Center for Astro and Particle Physics

We discuss a possible interpretation of the open charm mesons D＊s0 （2317）,D s1 （2460） and the hidden charm mesons X（3872）,Y（3940） and Y（4140） as hadron *** a phenomenological Lagrangian approach we review the strong and radiative decays of the D＊ s0 （2317） and D s1 （2460） *** X（3872） is assumed to consist dominantly of molecular hadronic components with an additional small admixture of a charmonium *** the radiative （γJ/ψ and γψ（2s）） and strong （J/ψ2π and J/ψ3π） decay modes we show that the present experimental observation is consistent with the molecular structure assumption of the X（3872）.Finally,we give evidence for molecular interpretations of the Y（3940） and Y（4140） related to the observed strong decay modes J/ψ＋ω or J/ψ＋φ,respectively.

关键词： charm mesons hadronic molecule strong and radiative decay

Spin excitation spectra of spin–orbit coupled bosons in an optical lattice

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Chinese Physics B 2015年第5期24卷 451-459页

作者：李若言贺亮孙青纪安春田光善 School of Physics Peking University institut für theoretische physik Leopold-Franzens Universitat Innsbruck Department of Physics Capital Normal University

Spin-wave excitation plays important roles in the investigation of the magnetic phases. In this paper, we study the spin-wave excitation spectra of two-component Bose gases with spin-orbit coupling in a deep square optical lattice using the spin-wave theory. We find that, while the excitation spectrum of the vortex crystal phase is gapless with a linear dispersion in the vicinity of the minimum point, the spectra of the commensurate spiral spin phase and the skyrmion crystal phase are gapped. Significantly, the spin fluctuations strongly destabilize the classical ground state of the skyrmion phase with the appearance of an imaginary part in the eigenfrequencies of spin excitations. Such features of the spin excitation spectra provide further insights into the exotic spin phases.

关键词： ultracold Fermi gas optical lattice spin-orbit coupling spin excitation spectrum