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The radiative decay of scalar glueball from lattice qcd

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 63-74页

作者： Jintao Zou Long-Cheng Gui Ying Chen Wen Qin Jian Liang Xiangyu Jiang Yibo Yang Department of Physics Hunan Normal University and Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of EducationChangsha 410081China Synergetic Innovation Center for Quantum Effects and Applications(SICQEA) Hunan Normal UniversityChangsha 410081China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Key Laboratory of Atomic and Subatomic Structure and Quantum Control(MOE) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of MatterInstitute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Guangdong Provincial Key Laboratory of Nuclear ScienceSouthern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou 510006China 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 International Centre for Theoretical Physics Asia-Pacific Beijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

We perform the first lattice qcd study on the radiative decay of the scalar glueball to the vector mesonφin the quenched *** calculations are carried out on three gauge ensembles with different lattice spacings,which enable us to do the continuum *** first revisit the radiative J/ψdecay into the scalar glueball G and obtain the partial decay widthΓ(J/ψ→γG)=0.578(86)keV and the branching fraction Br(J/ψ→γG)=6.2(9)×10^(-3),which are in agreement with the previous lattice *** then extend the similar calculation to the process G→γφand get the partial decay widthΓ(G→γφ)=0.074(47)keV,which implies that the combined branching fraction of J/ψ→γG→γγφis as small as O(10^(-9))such that this process is hardly detected by the BESⅢexperiment even with the large J/ψsample of O(10^(10)).With the vector meson dominance model,the two-photon decay width of the scalar glueball is estimated to beΓ(G→γγ)=0.53(46)e V,which results in a large stickiness S(G)~O(10^(4))of the scalar glueball by assuming the stickiness of f_(2)(1270)to be one.

关键词： lattice qcd scalar glueball radiative decay

Exploring hidden-charm and hidden-strange hexaquark states from lattice qcd

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 30-37页

作者： Hang Liu Jinchen He Liuming Liu Peng Sun Wei Wang Yi-Bo Yang Qi-An Zhang INPAC Key Laboratory for Particle Astrophysics and Cosmology(MOE)Shanghai Key Laboratory for Particle Physics and CosmologySchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Maryland Center for Fundamental Physics Department of PhysicsUniversity of MarylandCollege ParkMaryland 20742USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjing 210023China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing 100049/Hangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Physics Beihang UniversityBeijing 102206China

Based on five different ensembles of newly generated(2+1)-flavor configurations with pion mass of approximately mπ■(140-310)MeV,we present a lattice analysis of hidden-charm and hidden-strange hexaquarks with the quark content■.The correlation matrices of two types of operators with JPC=0++,0-+,1++and 1--are simulated to extract the masses of the hexaquark candidates,which are subsequently extrapolated to the physical pion mass and continuum *** results indicate that ground state masses are below the■threshold and provide a characteristic signal for the experimental discovery of hexaquark candidates,which may enrich the versatile structure of multiquarks;moreover,it is an indispensable step to decipher the nonperturbative nature of the fundamental interactions of quarks and gluons.

关键词： quantum chromodynamics lattice qcd multiquark states

lattice qcd Calculation of ππ Scattering Length

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Communications in Theoretical Physics 2012年第1期57卷 78-84页

作者： FU Zi-Wen Key Laboratory of Radiation Physics and Technology(Sichuan University) Ministry of EducationInstitute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China

We study s-wave pion-pion scattering length in lattice qcd for pion masses ranging from 330 MeV to 466 MeV. In the ＂Asqtad＂ improved staggered fermion formulation, we measure full ππ four-point correlators for isospin I = 0 and 2 channels, and use chiral perturbation theory at next-to-leading order to extrapolate our simulation results. Extrapolating to the physical pion mass yields scattering lengths as mna01=2 = -0.041 6（2） and mna01= 0.186（2） for isospin I = 2 and 0 channels, respectively. Our lattice simulation for ππ scattering length in I = 0 channel is an exploratory study, where we include the disconnected contribution, and our preliminary result is near to its experimental value. These simulations are carried out with MILC 2 ＋ 1 flavor gauge configurations at lattice spacing a ≈0.15 fm.

关键词： lattice qcd energy shift scattering length four point function

One-pion-exchange potential with contact terms from lattice qcd simulations

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Chinese Physics C 2020年第7期44卷 8-13页

作者： Jinniu Hu Ying Zhang Hong Shen Hiroshi Toki School of Physics Nankai UniversityTianjin 300071China Department of Physics Faculty of ScienceTianjin UniversityTianjin 300072China Research Center for Nuclear Physics(RCNP) Osaka UniversityIbarakiOsaka 567-0047Japan

Pion-mass-dependent nucleon-nucleon(NN)potentials are obtained in terms of the one-pion exchange and contact terms from the latest lattice qcd simulations of the two-nucleon *** assume the forms of the leading order(LO)NN potential from the chiral effective field theory and thus are referred to as the LO chiral potential in this *** extract the coefficients of contact terms and cut-off momenta in these potentials,for the first time,by fitting the phase shifts of 1S0 and 3S1 channels obtained from the HALqcd collaboration with various pion masses from 468.6 to 1170.9 *** low-energy constants in the 1S0 and 3S1 channels become weaker and approach each other for larger pion *** LO chiral potentials are applied to symmetric nuclear and pure neutron matter within the Brueckner-Hartree-Fock ***,however,we do not yet have the information of the P-wave NN interaction to be provided by the lattice qcd simulations for a complete description of nuclear *** results enhance understanding of the development of nuclear structure and nuclear matter by controlling the contribution of the pionic effect and elucidate the role of chiral symmetry of the strong interaction in complex systems.

关键词： chiral potentials lattice qcd nuclear matter

Calculation of disconnected quark loops in lattice qcd

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Chinese Physics C 2020年第3期44卷 52-58页

作者： Zhen Cheng Jian-Bo Zhang Guang-Yi Xiong Department of Physics Zhejiang UniversityHangzhou 310027China

Calculation of disconnected quark loops in lattice qcd is very time *** noise methods are generally used to estimate these ***,stochastic estimation gives large errors in the calculations of disconnected *** use the symmetric multi-probing source(SMP)method to estimate the disconnected quark loops,and compare the results with the Z(2)noise method and the spin-color explicit(SCE)method on a quenched lattice qcd ensemble with lattice volume 12^3×24 and lattice spacing a≈0.1 *** results show that the SMP method is very suitable for the calculation of pseudoscalar disconnected quark ***,the SMP and SCE methods do not have an obvious advantage over the Z(2)noise method in the evaluation of the scalar disconnected loops.

关键词： lattice qcd Wilson matrix disconnected quark loops Z(2)noise method SMP method

Baryon structure from lattice qcd

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Chinese Physics C 2009年第12期33卷 1093-1101页

作者： C. Alexandrou Department of Physics University of Cyprus P.O. Box 20357 Nicosia CY-1678 Cyprus Computation-based Science and Technology Research Center Cyprus Institute 20 Kavafi Street Nicosia 2121 Cyprus

We present recent lattice results on the baryon spectrum, nucleon electromagnetic and axial form factors, nucleon to △ transition form factors as well as the △ electromagnetic form factors. The masses of the low lying baryons and the nucleon form factors are calculated using two degenerate flavors of twisted mass fermions down to pion mass of about 270 MeV. We compare to the results of other collaborations. The nucleon to △ transition and △ form factors are calculated in a hybrid scheme, which uses staggered sea quarks and domain wall valence quarks. The dominant magnetic dipole nucleon to △ transition form factor is also evaluated using dynamical domain wall fermions. The momentum frame are extracted using the form factors transverse density distributions of the △ in the infinite determined from lattice qcd.

关键词： lattice qcd hadron spectrum nucleon form factors △ form factors and density distributions

Vector Meson Mass in Finite Density and Temperature lattice qcd

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Communications in Theoretical Physics 2015年第5期63卷 559-564页

作者：王睿陈莹宫明刘川刘玉斌刘朝峰马建平孟祥飞张剑波 School of Physics Nankai University Institute of High Energy Physics Chinese Academy of Sciences Theoretical Center for Science Facilities Chinese Academy of Sciences School of Physics and Center for High Energy Physics Peking University Collaborative Innovation Center of Quantum Matter Insititute of Theoretical Physics Chinese Academy of Sciences National Supercomputer Center in Tianjin Department of Physics Zhejiang University

Vector meson mass values are studied at finite chemical potential and temperature in lattice qcd with lattice size of 24 × 122× 6 using two flavors of staggered quarks. The investigation focuses on the change of the vector meson mass in the critical region close to T c with two different types of chemical potentials switched on: the isoscalar chemical potential μS and its isovector counterpart μV. It is found that the vector meson mass increases in the QGP phase with both chemical potentials and decreases with μS in the confinement phase.

关键词： lattice qcd numerical simulation vector meson

Diquark mass differences from unquenched lattice qcd

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Chinese Physics C 2016年第7期40卷 43-54页

作者：毕玉江蔡浩陈莹宫明刘朝峰乔豪学杨一玻 School of Physics and Technology Wuhan Universitv Wuhan 430072 China Institute of High Energy Physics and Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China Department of Physics and Astronomy University of Kentucky Lexington KY 40506 USA

We calculate diquark correlation functions in the Landau gauge on the lattice using overlap valence quarks and 2＋1flavor domain wall fermion configurations. Quark masses are extracted from the scalar part of quark propagators in the Landau gauge. The scalar diquark quark mass difference and axial vector scalar diquark mass difference are obtained for diquarks composed of two light quarks and of a strange and a light quark. The light sea quark mass dependence of the results is examined. Two lattice spacings are used to check the discretization effects. The coarse and fine lattices are of sizes 24^3 ×64 and 32^3 ×64 with inverse spacings 1/a= 1.75（4） GeV and 2.33（5） GeV, respectively.

关键词： lattice qcd diquarks overlap fermions Landau gauge

Charmed andϕmeson decay constants from 2+1-flavor lattice qcd

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Chinese Physics C 2021年第2期45卷 200-210页

作者： Ying Chen Wei-Feng Chiu Ming Gong Zhaofeng Liu Yunheng Ma Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China

On a lattice with 2+1-flavor dynamical domain-wall fermions at the physical pion mass,we calculate the decay constants of D_s^(*) , D^(*) ,and φ .The lattice size is 48^3×96 ,which corresponds to a spatial extension of -5.5 fm,with a lattice spacing of a\approx a≈0.114 *** the valence light,strange,and charm quarks,we use overlap fermions at several mass points close to their physical *** results at the physical point are f_(D)=213(5) MeV, f_(D)_(s)=249(7) MeV, f_(D)^(*)=234(6) MeV, f_(D)_(s)^(*)=274(7) MeV,and f_(D)_(s)=241(9) *** couplings of D^(*) and D_s^(*) to the tensor current( f_(V)^(T) )can be derived from ratios f_(D)^(*)^T/f_(D)^(*)=0.91(4) and f_(D)_(s)^(*)^T/f_(D)_(s)^(*)=0.92(4) ,respectively,which are the first lattice quantum chromodynamics(qcd)*** also obtain ratios f_(D)^(*)/f_(D)=1.10(3) and f_(D)_(s)^(*)/f_(D)_(s)=1.10(4) ,which reflect the size of heavy quark symmetry breaking in charmed *** f_(D)_(s)/f_(D)=1.16(3) and f_(D)_(s)^(*)/f_(D)^(*)=1.17(3) can be taken as a measure of SU(3)flavor symmetry breaking.

关键词： charmed mesons decay constants vector mesons quark flavor physics lattice qcd overlap fermions leptonic decays