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Isospin violation,light quark masses,and all that

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Chinese Physics C 2010年第9期34卷 1163-1168页

作者： ulf-g.meiβner HISKP and Bethe Center for Theoretical Physics Universitt Bonn IKP-3 IAS-4 and JCHPForschungszentrum Jülich

Isospin violation is driven through the light quark mass difference and electromagnetic effects.I review recent progress in extracting the light quark mass difference and tests of the chiral dynamics of Quantum Chromo... 详细信息

关键词： quantum chromodynamics isospin violation quark masses chiral Lagrangians

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利用机器学习研究隐粲五夸克态的性质

Science Bulletin 2023年第10期68卷 981-989,M0003页

作者：张振宇刘家豪胡继峰王倩 ulf-g.meißner guangdong Provincial Key Laboratory of Nuclear Science Institute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China guangdong-Hong Kong Joint Laboratory of Quantum Matter Southern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou 510006China Helmholtz-Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universität BonnBonn D-53115Germany Institute for Advanced Simulation Institut für Kernphysik and Jülich Center for Hadron PhysicsForschungszentrum JülichJïlich D-52425Germany Tbilisi State University Tbilisi 0186Georgia

机器学习已经在生物、医学、生产等多个领域广泛应用并展现了其优势.最近,机器学习在物理领域也开始逐渐兴起并展现出其独特的优点.该文旨在探索机器学习在强子物理中的应用潜力.作者以隐粲五夸克态Pc(4312)、Pc(4440)和Pc(4457)为例,... 详细信息

机器学习已经在生物、医学、生产等多个领域广泛应用并展现了其优势.最近,机器学习在物理领域也开始逐渐兴起并展现出其独特的优点.该文旨在探索机器学习在强子物理中的应用潜力.作者以隐粲五夸克态Pc(4312)、Pc(4440)和Pc(4457)为例,在强子分子态图像下研究它们的性质.研究表明,神经网络方法和基于χ2的拟合方法都能够阐明基于领头阶接触势的基本物理性质.然而,χ2拟合方法无法区分Pc(4440)和Pc(4457)的量子数,神经网络方法则可以.由此,作者进一步分析了每个实验数据点对于神经网络预测的影响,以及在拟合方法中每个数据点对于关键物理参数的重要性.通过对比研究,作者发现神经网络方法可以多维度地利用实验数据信息,在强子物理中具有巨大的应用前景.

关键词： Exotic hadrons Machine learning QCD mass spectrum Hidden charm pentaquarks

On the constituent counting rule for hard exclusive processes involving multi-quark states

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Chinese Physics C 2017年第5期41卷 91-96页

作者：郭奉坤 ulf-g.mei?ner 王伟 State Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of Sciences Helmholtz-Institut fr Strahlen- und Kernphysik and Bethe Center for Theoretical Physics Universitt Bonn Institute for Advanced Simulation Institut fr Kernphysik and Jlich Center for Hadron PhysicsForschungszentrum Jlich INPAC Shanghai Key Laboratory for Particle Physics and CosmologyDepartment of Physics and AstronomyShanghai Jiao-Tong University

At high energy,the cross section at finite scattering angle of a hard exclusive process falls off as a power of the Manderstam variable *** all involved quark-gluon compositions undergo hard momentum transfers,the fall-off scaling is determined by the underlying valence structures of the initial and final hadrons,known as the constituent counting *** spite of the complication due to helicity conservation,it has been argued that when applied to exclusive process with exotic multiquark states,the counting rule is a powerful way to determine the valence degrees of freedom inside hadron *** this work,we demonstrate that for hadrons with hidden flavors,the naive application of the constituent counting rule is problematic,since it is not mandatory for all components to participate in hard scattering at the scale s1/*** illustrate the problems in the viewpoint based on effective field *** clarify the misleading results that may be obtained from the constituent counting rule in exclusive processes with exotic candidates such as Z_c~±（cd/cu）,Z_b~±（bd/bdu）,X（3872）,etc.

关键词： quark exclusive constituent hadron meson exotic problematic clarify momentum valence

Double heavy tri-hadron bound state via delocalized π bond

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Chinese Physics C 2019年第1期43卷 96-102页

作者：马力王倩 ulf-g.meiβner Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics Universit?t Bonn Institut für Kernphysik Institute for Advanced Simulation and Jülich Center for Hadron Physics Forschungszentrum

The number of exotic candidates that are beyond the conventional quark model has increased dramatically over recent *** of these can be viewed as analogues of the ***,the existence of the triton indicates that bound states formed by three hadrons could also *** illustrate this possibility,we study the DD~*K and■systems using the Born-Oppenheimer *** leading order,only one-pion exchange potentials are *** means that the three constituents share one virtual *** is similar to the role of the delocalizedπbond for the formation of benzene in *** solving the Schr?dinger equation,we find two three-body DD~*K and■ bound states with masses 4317.92~_(-6.55)(+6.13)Me V and11013.65_(-8.84)^(+8.49)Me V,*** masses of their ■and■ analogues are 4317.92~_(-6.55)(+6.13)Me V and11013.65_(-9.02)^(+8.68)Me V,*** the experimental side,the ■bound state could be found by analyzing the current world data on the B→J/ψππKprocess,by focusing on the J/ψπK channel.

关键词： three-body system molecular state Schrodinger equation

Towards the continuum coupling in nuclear lattice effective field theory Ⅰ: A three-particle model

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Chinese Physics C 2020年第12期44卷 177-183页

作者：吴佳俊 ulf-g.meißner School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Helmholtz-Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universität BonnD-53115 BonnGermany Institute for Advanced Simulation Institut für Kernphysikand Jülich Center for Hadron PhysicsForschungszentrum JülichD-52425 JülichGermany Tbilisi State University 0186 TbilisiGeorgia

Weakly bound states often occur in nuclear *** precisely understand their properties,the coupling to the continuum should be worked out *** the first step,we use a simple nuclear model in the continuum and on a lattice to investigate the influence of a third particle on a loosely bound state of a particle and a heavy *** approach is consistent with the Lüscher formalism.

关键词： nuclear lattice effective field theory continuum coupling Hamiltonian method

How the X(5568) Challenges Our Understanding of QCD

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Communications in Theoretical Physics 2016年第5期65卷 593-595页

作者：郭奉困 ulf-g.mei?ner 邹冰松 Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Helmholtz-Institut fur Strahlen- und Kernphysik and Bethe Center for Theoretical Physics Universitat Bonn Institute for Advanced Simulation Institut fur Kernphysik and Julich Center for Hadron PhysicsForschungszentrum Julich School of Physical Sciences University of Chinese Academy of Sciences

We discuss the X(5568)particle recently announced by the D0 *** types of models were proposed to explain this structure in the *** pointed out by Burns and Swanson(ar Xiv:1603.04366),none of them provides a satisfactory description of the *** provide additional arguments using general properties of QCD,and conclude that the observation of the X(5568),if confirmed,poses serious challenges to our understanding of nonperturbative QCD.

关键词：非微扰QCD 类模型粒子

Wilsonian Renormalization group and the Lippmann-Schwinger Equation with a Multitude of Cutoff Parameters

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Communications in Theoretical Physics 2018年第3期69卷 303-307页

作者： E.Epelbaum J.gegelia ulf-g.meiβner Institut fur Theoretische Physik II Ruhr-Universitat Bochum D-44780 Bochum Germany Institute for Advanced Simulation Institut fur Kernphysik and Julich Center for Hadron Physics Forschungszentrum Jiilich D-52425 Julich Germany Tbilisi State University 0186 Tbilisi Georgia Helmholtz Institut fur Strahlen und Kernphysik and Bethe Center for Theoretical Physics Universitat Bonn D-53115 Bonn Germany

The Wilsonian renormalization group approach to the Lippmann-Schwinger equation with a multitude of cutoff parameters is introduced.A system of integro-differential equations for the cutoff-dependent potential is *** an illustration,a perturbative solution of these equations with two cutoff parameters for a simple case of an S-wave low-energy potential in the form of a Taylor series in momenta is *** relevance of the obtained results for the effective field theory approach to nucleon-nucleon scattering is discussed.

关键词：正常化方程域理论微分泰勒

Triviality of Quantum Electrodynamics Revisited

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Communications in Theoretical Physics 2018年第3期69卷 263-265页

作者： D.Djukanovic J.gegelia ulf-g.meiβner Helmholtz Institute Mainz University of MainzD-55099 MainzGermany Institute for Advanced Simulation Institut flit Kernphysik and Julich Center for Hadron PhysicsForschungszentrum JulichD-52425 JfilichGermany Tbilisi State University 0186 TbilisiGeorgia Helmholtz Institut fiir Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universitat BonnD-53115 BonnGermany

Quantum electrodynamics is often considered to be a trivial *** is based on a number of evidences,both numerical and *** of the strong indications for triviality of QED is the existence of the Landau pole for the running *** show that by treating QED as the leading order approximation of an effective field theory and including the next-to-leading order corrections,the Landau pole is *** also analyze the cutoff dependence of the bare coupling at two-loop order and conclude that the conjecture,that for reasons of self-consistency,QED needs to be trivial is a mere artefact of the leading order approximation to the corresponding effective field theory.

关键词： theory of quantized fields renormalization photons

Exploratory study of possible resonances in heavy meson-heavy baryon coupled-channel interactions

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Chinese Physics C 2018年第2期42卷 71-80页

作者：沈超玮 Deborah Rnchen ulf-g.meiβner 邹冰松 Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences (UCAS) Beijing 100049 China Helmholtz-Institut für Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics Universita Bonn D-53115 Bonn Germany

We use a unitary coupled-channel model to study the DAc-D∑c interactions. In our calculation, SU（3）flavor symmetry is applied to determine the coupling constants. Several resonant and bound states with different spin and parity are dynamically generated in the mass range of the recently observed pentaquarks. The approach is also extended to the hidden beauty sector to study the BΛb-B∑b interactions. As the b-quark mass is heavier than the c-quark mass, there are more resonances observed for the BΛb-B∑b interactions and they are more tightly bound.

关键词： coupled-channel interactions heavy meson heavy baryon exotic baryons