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arXiv 2020年

作者： Tan, Yue Lu, Weichang Ping, Jialun Dept. of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

Inspired by Ξccreported by LHCb Collaboration and X(5568) reported by D0 Collaboration, the QQqq (Q = c, b, q = u, d) tetraquark states, are studied in the present work. With the help of Gaussian expansion method, two structures, diquark-antiquark and meson-meson, with all possible color configurations are investigated systematically in a chiral quark model to search for the possible stable states. The results show that there is no bound state in the isovector QQqq system, while there are rather deep bound states in the isoscalar bbqq, ccqq and bcqq systems. Mixing two structures of diquark-antidiquark and meson-meson can introduce more attractions and convert some unbound isoscalar states into shallow bound states. The large mass of the heavy quark is beneficial to the formation of the bound state. The separations between quarks are calculated to unravel the spacial structure of the system. Copyright © 2020, The Authors. All rights reserved.

关键词： Hadrons

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Triply charm and bottom tetraquarks in a constituent quark model

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Physical Review D 2024年第5期110卷 054036页

作者： Gang Yang Jialun Ping Jorge Segovia Department of Physics Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Departamento de Sistemas Físicos Químicos y Naturales

Singly, doubly, and fully charmed tetraquark candidates, e.g., Tcs¯(2900), Tcc+(3875), and X(6900) have been recently reported by the LHCb collaboration. Therefore, it is timely to implement a theoretical investigation on triply heavy tetraquark systems; herein, the S-wave triply charm and bottom tetraquarks, Q¯Qq¯Q (q=u,d,s;Q=c,b), with spin-parity JP=0+, 1+, and 2+, isospin I=0 and 12, are systematically studied in a constituent quark model. Besides, all tetraquark configurations, i.e., meson-meson, diquark-antidiquark, and K-type arrangements, along with any allowed color structure, are comprehensively considered. The Gaussian expansion method (GEM), in combination with the complex-scaling method (CSM), which is quite ingenious in dealing with either bound or resonances, is the approach adopted in solving the complex scaled Schrödinger equation. This theoretical framework has already been applied in various tetra- and pentaquark systems. In a fully coupled-channel calculation within the GEM+CSM, narrow resonances are found in each I(JP) channel of the charm and bottom sector. In particular, triply charm and bottom tetraquark resonances are obtained in 5.6–5.9 GeV and 15.3–15.7 GeV, respectively. We provide also some insights of the compositeness of these exotic states, such as the inner quark distance, magnetic moment and dominant wave function component. All this may help to distinguish them in future high energy nuclear and particle experiments.

关键词： Multiquark bound states Quantum chromodynamics Quark model Strong interaction

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The S- and P-wave low-lying baryons in the chiral quark model

arXiv

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arXiv 2017年

作者： Yang, Gang Ping, Jialun Segovia, Jorge Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China E-08193 Spain

The 1S, 2S, 1P and 2P states of light baryons are investigated within the chiral quark model, paying particular attention to the well-known order reverse problem of 1P and 2S states. Besides a nonperturbative linearscreened confining interaction and a perturbative one-gluon exchange between quarks, we incorporate the Goldstone-boson exchanges taking into account not only the full octet of pseudoscalar mesons but also the scalar one. The scalar meson exchange potential simulates the higher order multi-pion exchange terms that appear in the chiral Lagrangian and its omission has been already admitted as a deficiency of the original model in describing, for instance, the π - w splitting. The numerical approach to the three-body bound state problem is the so-called Gaußian expansion method, which is able to get a precision as good as Faddeev calculations. With a set of parameters fixed to different hadron and hadron-hadron observables, we find that the chiral potential could play an important role towards the issue on the mass order reverse problem. We extend our calculation to the qqQ and qQQ sectors (with q representing a light u-, d-, or s-quark and Q denoting the charm quark or the bottom one) in which many new states have been recently observed. Some tentative assignments are done attending to the agreement between theoretical and experimental masses;however, we admit that other sources of information are needed in order to make strong claims about the nature of these states. Copyright © 2017, The Authors. All rights reserved.

关键词： Hadrons

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Investigating the excited Ωc0 states through ΞcK¯ and Ξc′K¯ decay channels

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Physical Review D 2018年第3期97卷 034027-034027页

作者： Hongxia Huang Jialun Ping Fan Wang Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing 210023 China Department of Physics Nanjing University Nanjing 210093 China

Inspired by the five newly observed Ωc0 states by the LHCb detector, we study the Ωc0 states as the S-wave molecular pentaquarks with I=0, JP=12−, 32−, and 52− by solving the renormalization group method equation in the framework of the chiral quark model. Both the energies and the decay widths are obtained in this work. Our results suggest that Ωc(3119)0 can be explained as an S-wave resonance state of ΞD with JP=12−, and the decay channels are the S-wave ΞcK¯ and Ξc′K¯. Other reported Ωc0 states cannot be obtained in our present calculation. Another Ωc0 state with much higher mass 3533 MeV with JP=52− is also obtained. In addition, the calculation is extended to the Ωb0 states, and results similar to those of Ωc0 are obtained.

关键词： Hadron-hadron interactions Quark model

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Triply heavy baryons in the constituent quark model

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Chinese Physics C 2020年第2期44卷 33-41页

作者： Gang Yang Jialun Ping Pablo GOrtega Jorge Segovia Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics Tsinghua UniversityBeijing 100084China Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal UniversityNanjing 210023China Grupo de Física Nuclear and Instituto Universitario de Física Fundamental y Matemáticas(IUFFyM) Universidad de SalamancaE-37008 SalamancaSpain Departamento de Sistemas Físicos Químicos y NaturalesUniversidad Pablo de OlavideE-41013 SevillaSpain

The constituent quark model is used to compute the ground and excited state masses of QQQ baryons containing either c or b *** quark model parameters previously used to describe the properties of charmonium and bottomonium states were used in this *** non-relativistic three-body bound state problem is solved by means of the Gaussian expansion method which provides sufficient accuracy and simplifies the subsequent evaluation of the matrix *** low-lying states with quantum numbers J^P=1/2^±,3/2^±,5/2^±and 7/2^+are *** compare the results with those obtained by the other theoretical *** is a general agreement for the mass of the ground state in each sector of triply heavy ***,the situation is more puzzling for the excited states,and appropriate comments about the most relevant features of our comparison are given.

关键词： Quantum Chromodynamics quark models properties of baryons exotic baryons

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Linear Array Synthesis Based on Artificial Neural Network Agent Model with Fast Fourier Transform

Linear Array Synthesis Based on Artificial Neural Network Ag...

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International Conference on Microwave and Millimeter Wave Technology Proceedings

作者： Aowei Li Jiahao Liu Xin Zhang Zhe Liu Foxiang Liu School of Information Engineering Nanchang University Nanchang China Key Laboratory of Numerical Simulation for Large Scale Complex Systems Ministry of Education

ISBN: (数字)9798350389968

ISBN: (纸本)9798350389975

This paper introduces a new array synthesis method based on back propagation (BP) neural network agent model with a training set quickly generated by fast Fourier transform. Moreover, it can be conveniently generalized to array models on different scenarios. A test example for synthesizing uniformly spaced linear array with non-uniform excitations is conducted. Synthesis results prove the effectiveness and superiority of the proposed method.

关键词： Training Microwave technology Microwave integrated circuits Fast Fourier transforms Millimeter wave technology Training data Prediction algorithms

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Study of Bs←φ+- Decays in the PQCD Factorization Approach with Lattice QCD Input

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Advances in High Energy Physics 2021年 2021卷

作者： Jin, Su-Ping Xiao, Zhen-Jun Department of Physics and Institute of Theoretical Physics Nanjing Normal University NanjingJiangsu210023 China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

In this paper, we studied systematically the semileptonic decays Bs←φl+l- with l-=e-,μ-,τ- by using the perturbative QCD (PQCD) and the "PQCD+Lattice"factorization approach, respectively. We first evaluated all relevant form factors Fiq2 in the low-q2 region using the PQCD approach, and we also took the available lattice QCD results at the high-q2 region as additional input to improve the extrapolation of Fiq2 from the low-q2 region to the endpoint qmax2. We then calculated the branching ratios and many other physical observables AFBl, FLφ, S3,4,7, and A5,6,8,9 and the clean angular observables P1,2,3 and P4,5,6,8′. From our studies, we find the following points: (a) the PQCD and "PQCD+Lattice"predictions of BBs←φμ+μ- are about 7×10-7, which agree well with the LHCb measured values and the QCD sum rule prediction within still large errors;(b) we defined and calculated the ratios of the branching ratios Rφeμ and Rφμτ;(c) the PQCD and "PQCD+Lattice"predictions of the longitudinal polarization FL, the CP-averaged angular coefficients S3,4,7, and the CP asymmetry angular coefficients A5,6,8,9 agree with the LHCb measurements in all considered bins within the still large experimental errors;and (d) for those currently still unknown observables Rφeμ,Rφμτ,AFBl,P1,2,3, and P4,5,6,8′, we suggest LHCb and Belle-II Collaboration to measure them in their experiments. © 2021 Su-Ping Jin and Zhen-Jun Xiao.

关键词： Forecasting

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General theory for designing phonon transport in alloyed/doped materials

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Science China(Physics,Mechanics & Astronomy) 2024年第12期67卷 133-140页

作者： Chenhan Liu Chao Wu Wei Liu Yunshan Zhao Gang Zhang Hongmin Yang Yunfei Chen Micro-and Nano-scale Thermal Measurement and Thermal Management Laboratory Key Laboratory of Numerical Simulation for Large Complex SystemsMinistry of EducationSchool of Energy and Mechanical EngineeringNanjing Normal UniversityNanjing210023China School of Electrical and Automation Engineering Nanjing Normal UniversityNanjing210023China Phonon Engineering Research Center of Jiangsu Province Center for Quantum Transport and Thermal Energy ScienceInstitute of Physics Frontiers and Interdisciplinary SciencesSchool of Physics and TechnologyNanjing Normal UniversityNanjing210023China Agency for Science Technology and ResearchInstitute of High-Performance ComputingSingapore138632Singapore Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments School of Mechanical EngineeringSoutheast UniversityNanjing211100China

Alloying/doping is a widely used technique for improving the electrical,mechanical,and optical properties of ***,this technology induces significant distortions in the lattice structure,mass distribution,and potential field,greatly enhancing phonon ***,we introduce the concept of alloying/doping path and employ crystal symmetry,lattice deformation,and electron distribution to characterize *** on this new concept,the phonon thermal transport behavior in alloyed/doped materials can be well designed,and along different alloying/doping paths,the difference in thermal conductivity can be up to 45 *** one hand,strategic alloying/doping that combines high crystal symmetry,large lattice contraction,and the same electron distribution suppresses phonon-phonon scattering phase space,induces phonon stiffening,and bolsters electronic structure symmetry,*** synergistic effects significantly improve thermal *** the other hand,random alloying/doping has a low symmetry,leading to the typical“U”shape of alloying/doping level-dependent thermal *** theory is corroborated in three-dimensional(3D)Si,2D MoS_(2),and quasi-1D TiS_(3),affirming its efficacy and broad applicability in controlling phonon transport.

关键词： phonon transport alloyed/doped materials crystal symmetry lattice contraction electronic structure

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Delocalizedπ_(3)^(6) Bond in OX_(2) (X=Halogen) Molecules

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Chinese Journal of Chemical Physics 2022年第3期35卷 542-550,I0003页

作者： Yi-han Tang Pu Yang Meng-yuan Chen Yu-ru Wang Jia-xin Wang Jia-wei Xu School of Petrochemical Engineering Changzhou UniversityChangzhou 213164China Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Key Laboratory of Numerical Simulation of Large Scale Complex System Nanjing Normal UniversityNanjing 210023China

OX_(2)(X=halogen)molecules was studied *** results show that delocalizedπ_(3)^(6) bonds exist in their electronic structures and O atoms adopt the sp^(2) type of hybridization,which violates the prediction of the valence shell electron pair repulsion theory of sp^(3) *** stabilization energy is proposed to measure the contribution of delocalizedπ_(3)^(6) bond to energy decrease and proves to bring extra-stability to the *** phenomena can be summarized as a kind of coordinating effect.

关键词： Theoretical and computational chemistry Valence shell electron pair repulsion theory Delocalizedπbond Delocalization stabilization energy Dihalogen monoxide

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Impacts of major volcanic eruptions over the past two millennia on both global and Chinese climates:A review

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Science China Earth Sciences 2024年第1期67卷 61-78页

作者： Weiyi SUN Deliang CHEN Guonian LÜ Liang NING Chaochao GAO Renhe ZHANG Bin WANG Jian LIU Key Laboratory for Virtual Geographic Environment Ministry of EducationState Key Laboratory Cultivation Base of Geographical Environment Evolution of Jiangsu ProvinceJiangsu Center for Collaborative Innovation in Geographical Information Resource Development and ApplicationSchool of Geography ScienceNanjing Normal UniversityNanjing 210023China Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg 40530Sweden College of Environmental and Resource Science Zhejiang UniversityHangzhou 310058China Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200437China Department of Atmospheric Sciences and Atmosphere-Ocean Research Center University of Hawaii at ManoaHonoluluHI 96825USA Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical ScienceNanjing Normal UniversityNanjing 210023China Open Studio for the Simulation of Ocean-Climate-Isotope Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China

Major volcanic eruptions(MVEs)have attracted increasing attention from the scientific *** studies have explored the climatic impact of MVEs over the past two ***,proxy-based reconstructions and climate model simulations indicate divergent responses of global and China’s regional climates to ***,we used multiple data from observations,reconstructions,simulations,and assimilations to summarize the historical facts of MVEs,the characteristics and mechanisms of their climatic impact,and directions for future *** reviewed volcanic datasets and determined intensive MVE periods;these periods corresponded to the years 530–700,1200‒1460,and 1600‒1840 *** tropical MVEs,a substantial cooling effect is observed throughout the globe and China on the interannual-interdecadal time scales but an inconsistent cooling magnitude is detected between reconstructions and *** the first summer after tropical MVEs,a decrease in global and monsoonal precipitation is *** reconstructions and simulations,an increased precipitation is seen for the Yangtze River Basin,while large uncertainties in precipitation changes are present for other regions of *** drought can be induced by frequent eruptions and volcanism superimposed on low solar irradiation and internal *** affect climate directly through the radiative effect and indirectly by modulating internal variability,such as the El Niño‒Southern Oscillation(ENSO)and Atlantic Multidecadal Oscillation(AMO).However,changes in the phase,amplitude,and periodicity of ENSO and AMO after MVEs and the associated mechanisms remain controversial,which could account for model-reconstruction ***,other internal variability,uncertainties in reconstruction methods and aerosol‒climate models,and climate background may also induce model-reconstruction *** gaps and directions for future research are also discussed.

关键词： Major volcanic eruption Climate variability Mechanism Past two millennia Internal variability

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