There has recently been a dramatic renewal of interest in hadron spectroscopy and charm physics. This renaissance has been driven in part by the discovery of a plethora of charmonium-like XYZ states at BESⅢ and B fac...There has recently been a dramatic renewal of interest in hadron spectroscopy and charm physics. This renaissance has been driven in part by the discovery of a plethora of charmonium-like XYZ states at BESⅢ and B factories, and the observation of an intriguing proton-antiproton threshold enhancement and the possibly related X(1835) meson state at BESⅢ, as well as the threshold measurements of charm mesons and charm baryons. We present a detailed survey of the important topics in tau-charm physics and hadron physics that can be further explored at BESⅢ during the remaining operation period of BEPCⅡ. This survey will help in the optimization of the data-taking plan over the coming years, and provides physics motivation for the possible upgrade of BEPCⅡ to higher luminosity.展开更多
Heavy Ion Fusion makes use of the Relativistic Heavy Ion Collider at Brookhaven National Lab and the Large Hadron Collider in Geneva, Switzerland for Inertial Confinement Fusion. Two Storage Rings, which may or may no...Heavy Ion Fusion makes use of the Relativistic Heavy Ion Collider at Brookhaven National Lab and the Large Hadron Collider in Geneva, Switzerland for Inertial Confinement Fusion. Two Storage Rings, which may or may not initially be needed, added to each of the Colliders increases the intensity of the Heavy Ion Beams making it comparable to the Total Energy delivered to the DT target by the National Ignition Facility at the Lawrence Livermore Lab. The basic Physics involved gives Heavy Ion Fusion an advantage over Laser Fusion because heavy ions have greater penetration power than photons. The Relativistic Heavy Ion Collider can be used as a Prototype Heavy Ion Fusion Reactor for the Large Hadron Collider.展开更多
Present studies in physics assume that elementary particles are the building blocks of all matter, and that they are zero-dimensional objects which do not occupy space. The new I-Theory predicts that elementary partic...Present studies in physics assume that elementary particles are the building blocks of all matter, and that they are zero-dimensional objects which do not occupy space. The new I-Theory predicts that elementary particles do indeed have a substructure, three dimensions, and occupy space, being composed of fundamental particles called I-particles. In this article we identify the substructural pattern of elementary particles and define the quanta of energy that form each elementary particle. We demonstrate that the substructure comprises two classes of quanta which we call “attraction quanta” and “repulsion quanta”. We create a model that defines the rest-mass energy of each elementary particle and can predict new particles. Lastly, in order to incorporate this knowledge into the contemporary models of science, a revised periodic table is proposed.展开更多
We survey contemporary studies of hadrons and strongly interacting quarks using QCD's Dyson-Schwinger equations, addressing the following aspects: confinement and dynamical chiral symmetry breaking; the hadron spe...We survey contemporary studies of hadrons and strongly interacting quarks using QCD's Dyson-Schwinger equations, addressing the following aspects: confinement and dynamical chiral symmetry breaking; the hadron spectrum; hadron elastic and transition form factors, from small-to large-Q2; parton distribution functions; the physics of hadrons containing one or more heavy quarks; and properties of the quark gluon plasma.展开更多
The medium-temperature T dependence of the jet transport coefficient̂q was studied via the nuclear modification factor RAA(p_(T))and elliptical flow parameter v_(2)(p_(T))for large transverse momentum p_(T) hadrons in...The medium-temperature T dependence of the jet transport coefficient̂q was studied via the nuclear modification factor RAA(p_(T))and elliptical flow parameter v_(2)(p_(T))for large transverse momentum p_(T) hadrons in high-energy nucleus-nucleus collisions.Within a next-to-leading-order perturbative QCD parton model for hard scatterings with modified fragmentation functions due to jet quenching controlled by q,we check the suppression and azimuthal anisotropy for large p_(T) hadrons,and extract q by global fits to RAA(pT)and v_(2)(pT)data in A+A collisions at RHIC and LHC,respectively.The numerical results from the best fits show that q∕T^(3) goes down with local medium-temperature T in the parton jet trajectory.Compared with the case of a constant q∕T^(3),the going-down T dependence of q∕T^(3) makes a hard parton jet to lose more energy near T_(c) and therefore strengthens the azimuthal anisotropy for large pT hadrons.As a result,v_(2)(p_(T))for large pT hadrons was enhanced by approximately 10%to better fit the data at RHIC/LHC.Considering the first-order phase transition from QGP to the hadron phase and the additional energy loss in the hadron phase,v_(2)(p_(T))is again enhanced by 5-10%at RHIC/LHC.展开更多
The attractive interaction between J/ψandψ(3770)has to be strong enough if X(6900)is of the molecule type.We argue that sinceψ(3770)decays predominantly into a DD^(¯)pair,the interactions between J/ψandψ(377...The attractive interaction between J/ψandψ(3770)has to be strong enough if X(6900)is of the molecule type.We argue that sinceψ(3770)decays predominantly into a DD^(¯)pair,the interactions between J/ψandψ(3770)may be significantly enhanced owing to the three point DD^(¯)loop diagram.The enhancement originates from the anomalous threshold located at t=−1.288 GeV^(2),whose effect propagates into the s-channel partial wave amplitude in the vicinity of √s≃6.94 GeV.This effect may be helpful in the formation of the X(6900)peak.展开更多
In this study,we conducted a search for dark matter using a part of the data recorded by the CMS experiment during run-I of the LHC in 2012 with a center of mass energy of 8 TeV and an integrated luminosity of 11.6 fb...In this study,we conducted a search for dark matter using a part of the data recorded by the CMS experiment during run-I of the LHC in 2012 with a center of mass energy of 8 TeV and an integrated luminosity of 11.6 fb−1.These data were gathered from the CMS open data.Dark matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.Thus,the search was conducted in the dimuon plus large missing transverse momentum channel.One benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the CMS open data.No evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.展开更多
The role of the triangle mechanism in the decay processes B_(0)→J/ψK^(0)f_(0)→J/ψK^(0)π^(+)π^(-)and B_(0)→J/ψK^(0)a_(0)→J/ψK^(0)π^(0)ηis probed.In these processes,the triangle singularity appears from the ...The role of the triangle mechanism in the decay processes B_(0)→J/ψK^(0)f_(0)→J/ψK^(0)π^(+)π^(-)and B_(0)→J/ψK^(0)a_(0)→J/ψK^(0)π^(0)ηis probed.In these processes,the triangle singularity appears from the decay of B_(0)intoJ/ψ∅K^(0),and then,∅decays intoK^(0)K^(0)andK^(0)K^(0)merged into f_(0)or a_(0),which finally decay intoπ^(+)π^(-)andπ^(0)η,respectively.We find that this mechanism leads to a triangle singularity around M_(inv)(K^(0)f_(0)(a_(0)))≈1520 MeV and gives sizable branching fractions Br(B_(0)→J/ψK^(0)f_(0)→J/ψK^(0)π^(+)π^(-))=7.67×10^(-7)and Br(B_(0)→J/ψK^(0)a_(0)→J/ψK^(0)π^(0)η)=1.42×10^(-7).This investigation can help us obtain the information of the scalar mesonf_(0)(980)or a_(0)(980).展开更多
The practice of using the direct ionization radiation (electrons, protons, antiprotons, pions, ions, etc) or of the indirect ionization radiation (photons, neutrons, etc) in economy and social life has led to the intr...The practice of using the direct ionization radiation (electrons, protons, antiprotons, pions, ions, etc) or of the indirect ionization radiation (photons, neutrons, etc) in economy and social life has led to the introduction of the absorbed dose magnitude (ICRU 1953) defined as the energy absorbed per mass unit of the irradiated substance. This is a fundamental magnitude valid for any type of ionizing radiation, any irradiated material and any radiation energy. In case of clinical hadron beams generated by conventional accelerators or those controlled by lasers, IAEA TRS 398 recommends the absorbed dose to water. This may be determined employing the calorimeter method with water or graphite, chemical method, fluence based measurements as Faraday cups or activation measurements, and the ionization chamber method. In this paper the selected method was the thimble air filled ionization chamber method for determination of absorbed dose to water.展开更多
Previously the 5D homogeneous space-time metric was introduced with explicitly given projection operators in matrix form which map the 5D space-time manifold into a Lorentzian space-time. Based on this projection mode...Previously the 5D homogeneous space-time metric was introduced with explicitly given projection operators in matrix form which map the 5D space-time manifold into a Lorentzian space-time. Based on this projection model, vector field and spinor solutions are found to be expressible in terms of SU(2)xL and SU(3)xL, where L is the 4D Lorentz space-time group. The spinor solutions give the SU(2) leptonic states arising from space-time projection, whereas the SU(3) representation arises from conformal projection and gives the quarks, and due to gauge requirement leads to mesons and baryons. This process of mapping the 5D space-time manifold into the 4D space-time is at the basis of an analysis of the recent CERN experimental results, the presence of neutrino oscillations and the observed 125 GeV resonance in the p-p collisions, respectively. In fact, it is found that the spinor solution contains an oscillating phase, and the 125 GeV resonance is shown to be predictable, thereby 1) eliminating the need to introduce a Higgs vacuum, and 2) can be shown possibly to be an indicator for a missing heavy baryon octet.展开更多
The simplest version of the dynamical holographic QCD model is described by adding the KKSS model action on a dilaton-graviton coupled background,in which the AdS5 metric is deformed by the gluon condensation and furt...The simplest version of the dynamical holographic QCD model is described by adding the KKSS model action on a dilaton-graviton coupled background,in which the AdS5 metric is deformed by the gluon condensation and further deformed by the chiral condensation.In this framework,both the chiral symmetry breaking and linear confinement can be realized.The light-flavor hadron spectra and the pion form factor were investigated,but it was difficult to reconcile the light-flavor hadron spectra and pion form factor.By considering the anomalous 5-dimension mass correction of the scalar field from QCD running coupling,it is found that the light flavor hadron spectra and pion form factor can be described well simultaneously.In particular,the ground state and lower excitation states of the scalar,pseudo scalar,and axial vector meson spectra are improved.However,the vector meson spectra are not sensitive to the anomalous 5-dimension mass correction of the scalar field.展开更多
Glueballs are investigated through gluonic operators on two N_(f)=2+1RBC/UKQCD gauge ensembles at the physical pion mass.The statistical errors of glueball correlation functions are considerably reduced through the cl...Glueballs are investigated through gluonic operators on two N_(f)=2+1RBC/UKQCD gauge ensembles at the physical pion mass.The statistical errors of glueball correlation functions are considerably reduced through the cluster decomposition error reduction(CDER)method.The Bethe-Salpeter wave functions are obtained for the scalar,tensor,and pseudoscalar glueballs by using spatially extended glueball operators defined through the gauge potential A_(μ)(x)in the Coulomb gauge.These wave functions exhibit similar features of non-relativistic two-gluon systems and are used to optimize the signals of the related correlation functions at the early time regions,where the ground state masses are extracted.These masses are close to those from the quenched approximation and indicate the possible existence of glueballs at the physical point.The resonance feature of glueballs and the mixing with conventional mesons and multi-hadron systems should be considered in a more systematic lattice study.展开更多
We report a search for a heavier partner of the recently observed Z_(cs)(3985)^(-) state,denoted as Z_(cs)^('-),in the process e^(+)e^(−)→K^(+)D_(s)^(∗−) D^(∗0 )+ c.c.,based on e^(*)e^(-)collision data collected ...We report a search for a heavier partner of the recently observed Z_(cs)(3985)^(-) state,denoted as Z_(cs)^('-),in the process e^(+)e^(−)→K^(+)D_(s)^(∗−) D^(∗0 )+ c.c.,based on e^(*)e^(-)collision data collected at the center-of-mass energies of √s=4.661,4.682 and 4.699 GeV with the BESIII detector.The Z_(cs)^('-) is of interest as it is expected to be a candidate for a hidden-charm and open-strange tetraquark.A partial-reconstruction technique is used to isolate K^(+)recoil-mass spectra,which are probed for a potential contribution from Z_(cs)^('-)→D_(s)^(∗−) D^(∗0 )+ c.c.We find an excess of Z_(cs)^('-)→D_(s)^(*-)-D^(*0)(c.c.)candidates with a significance of 2.1o,after considering systematic uncertainties,at a mass of(4123.5±0.7_(sat)±4.7_(syst.))MeV/c^(2).As the data set is limited in size,the upper limits are evaluated at the 90%confidence level on the product of the Born cross sections(σ^(Borm))and the branching fraction(B)of Z_(cs)^('-)→D_(s)^(*-)-D^(*0),under different assumptions of the Z_(cs)^('-) mass from 4.120 to 4.140 MeV and of the width from 10 to 50 MeV at the three center-of-mass energies.The upper limits of σ^(Born).B are found to be at the level of O(1)pb at each energy.Larger data samples are needed to confirm the Z_(cs)^('-) state and clarify its nature in the coming years.展开更多
Accessing a full image of the inner content of hadrons represents a central endeavour of modern particle physics,with the main scientific motivation to investigate the strong interaction binding the visible matter.On ...Accessing a full image of the inner content of hadrons represents a central endeavour of modern particle physics,with the main scientific motivation to investigate the strong interaction binding the visible matter.On the one hand,the structure of known exotic candidates is a fundamental open issue addressed widely by scientists.On the other hand,looking for new states of exotic nature is a central component for theoretical and experimental efforts from electron-positron machine and electron accelerator with fixed target to heavy ion and electron-ion colliders.In this article we present a succinct short overview of the attempt to search for exotic narrow N∗and Z states containing light quarks only or also charm,and its connotation for bottom regions(the latter two are also known as Pc(Zc)and Pb(Zb)states,respectively in the literature).We address the effort of searching for exotic narrow N∗and Z states in light quark sector.We focus on recent progress in searching for signal of Pc and Zc states photoproduction and its implication into the Pb and Zb photoproduction and their decay properties.We also discuss future perspectives for the field in electron-ion colliders,a good place to disentangle the nature of some of these states and investigate some other enlightening topics including QCD trace anomaly and quarkonium-nucleon scattering length.展开更多
The yields of X_(cscs)with its two possible configurations,i.e.,the hadronic molecular state and tetraquark state,for Pb-Pb collisions at√sNN=5.02 TeV is studied.A volume effect is found from the centrality distribut...The yields of X_(cscs)with its two possible configurations,i.e.,the hadronic molecular state and tetraquark state,for Pb-Pb collisions at√sNN=5.02 TeV is studied.A volume effect is found from the centrality distribution of X_(cscs),which could help to distinguish the inner structure of X_(cscs).We also show the rapidity and the transverse momentum distributions of X_(cscs) production as well as its elliptic flow coefficient as a function of the transverse momentum.展开更多
The inclusion of theρ−ωmixing effect is essential for a precise description of the pion electromagnetic form factor in the e+e−→π+π−process,which quantifies the two-pion contribution to the anomalous magnetic mom...The inclusion of theρ−ωmixing effect is essential for a precise description of the pion electromagnetic form factor in the e+e−→π+π−process,which quantifies the two-pion contribution to the anomalous magnetic moment of muon aμ.In this study,we analyze the momentum dependence ofρ−ωmixing by considering loop contributions at the next-to-leading order in 1/NC expansion within the framework of resonance chiral theory.We revisit a previous study[Y.H.Chen,D.L.Yao,and H.Q.Zheng,Commun.Theor.Phys.69,1(2018)]and consider the contribution arising from the kaon mass splitting in the kaon loops and latest experimental data.We perform two types of fits(with momentum-independent or momentum-dependentρ−ωmixing amplitude)to describe e+e−→π+π−andτ→ντ2πdata within the energy region of 600−900 MeV and decay width ofω→π+π−.Furthermore,we compare their results.Our findings indicate that the momentum-independent and momentum-dependentρ−ωmixing schemes provide appropriate descriptions of the data.However,the momentum-dependent scheme exhibits greater self-consistency,considering the reasonable imaginary part of the mixing matrix elementΠρωobtained.Regarding the contribution to the anomalous magnetic moment of the muon,aππμ|[0.6,0.9]GeV,the results obtained from the fits considering the momentum-dependentρ−ωmixing amplitude are in good agreement with those obtained without incorporating the momentum dependence ofρ−ωmixing,within the margin of errors.Furthermore,based on the fitted values of the relevant parameters,we observe that the decay width ofω→π+π−is predominantly influenced by theρ−ωmixing effect.展开更多
This study investigates the prospect of discovering strongly interacting gluinos in different multi-lepton channels with lepton multiplicities greater than or equal to 2 at LHC RUN-Ⅲ,considering several pMSSM scenari...This study investigates the prospect of discovering strongly interacting gluinos in different multi-lepton channels with lepton multiplicities greater than or equal to 2 at LHC RUN-Ⅲ,considering several pMSSM scenarios.The effectiveness of the multivariate analysis(MVA) method with the boosted decision tree(BDT) algorithm is explored to obtain a better significance for different models.Promising results are obtained for the 3-lepton channels,indicating that the use of MVA methods can improve the sensitivity of the search for gluinos at LHC RUN-Ⅲ.The study probes the multi-lepton signatures arising from gluinos via intermediate eweakinos and sleptons at an early stage of the LHC RUN-Ⅲ.The heavier eweakinos can give rise to three or four lepton signals,in which the squark hierarchy between the L and R types plays a crucial role.The study considers two sets of benchmark points that satisfy all the collider constraints obtained from the LHC RUN-Ⅱ data.Moreover,these sets of benchmark points are mostly consistent with WMAP/PLANCK data and the muon(g-2) constraint.The corresponding results from the MVA technique demonstrate that,even for an integrated luminosity of 270 fb-1,the 5 σ discovery prospect of3l+jets+ETfor Mg=1.8 TeV in the wino type model is promising.The study also presents various other models that may emerge at the early stage of LHC RUN-Ⅲ.Wino type models in the scenario where left squarks are light and right squarks are heavy exhibit the best prospect of discovering gluinos in multi-lepton channels in the LHC RUN-Ⅲ experiment.The findings of this study provide crucial insights into the potential discovery of gluinos in multi-lepton channels.展开更多
基金Supported in part by National Key Basic Research Program of China (2015CB856700)National Natural Science Foundation of China (NSFC) (11335008,11425524, 11625523, 11635010, 11735014, 11822506, 11935018)+18 种基金the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Programthe CAS Center for Excellence in Particle Physics (CCEPP)Joint Large-Scale Scientific Facility Funds of the NSFC and CAS (U1532257, U1532258, U1732263)CAS Key Research Program of Frontier Science (QYZDJ-SSW-SLH003, QYZDJ-SSW-SLH040)100 Talents Program of CASCAS PIFIthe Thousand Talents Program of ChinaIN-PAC and Shanghai Key Laboratory for Particle Physics and CosmologyGerman Research Foundation DFG under Contracts NosCollaborative Research Center CRC 1044, FOR 2359Istituto Nazionale di Fisica Nucleare, ItalyKoninklijke Nederlandse Akademie van Wetenschappen (KNAW) (530-4CDP03)Ministry of Development of Turkey (DPT2006K-120470)National Science and Technology fundThe Knut and Alice Wallenberg Foundation (Sweden) (2016.0157)The Swedish Research CouncilU. S. Department of Energy (DE-FG02-05ER41374, DESC-0010118, DE-SC-0012069)University of Groningen (Ru G) and the Helmholtzzentrum fuer Schwerionenforschung Gmb H (GSI), Darmstadtthe Russian Ministry of Science and Higher Education (14.W03.31.0026).
文摘There has recently been a dramatic renewal of interest in hadron spectroscopy and charm physics. This renaissance has been driven in part by the discovery of a plethora of charmonium-like XYZ states at BESⅢ and B factories, and the observation of an intriguing proton-antiproton threshold enhancement and the possibly related X(1835) meson state at BESⅢ, as well as the threshold measurements of charm mesons and charm baryons. We present a detailed survey of the important topics in tau-charm physics and hadron physics that can be further explored at BESⅢ during the remaining operation period of BEPCⅡ. This survey will help in the optimization of the data-taking plan over the coming years, and provides physics motivation for the possible upgrade of BEPCⅡ to higher luminosity.
文摘Heavy Ion Fusion makes use of the Relativistic Heavy Ion Collider at Brookhaven National Lab and the Large Hadron Collider in Geneva, Switzerland for Inertial Confinement Fusion. Two Storage Rings, which may or may not initially be needed, added to each of the Colliders increases the intensity of the Heavy Ion Beams making it comparable to the Total Energy delivered to the DT target by the National Ignition Facility at the Lawrence Livermore Lab. The basic Physics involved gives Heavy Ion Fusion an advantage over Laser Fusion because heavy ions have greater penetration power than photons. The Relativistic Heavy Ion Collider can be used as a Prototype Heavy Ion Fusion Reactor for the Large Hadron Collider.
文摘Present studies in physics assume that elementary particles are the building blocks of all matter, and that they are zero-dimensional objects which do not occupy space. The new I-Theory predicts that elementary particles do indeed have a substructure, three dimensions, and occupy space, being composed of fundamental particles called I-particles. In this article we identify the substructural pattern of elementary particles and define the quanta of energy that form each elementary particle. We demonstrate that the substructure comprises two classes of quanta which we call “attraction quanta” and “repulsion quanta”. We create a model that defines the rest-mass energy of each elementary particle and can predict new particles. Lastly, in order to incorporate this knowledge into the contemporary models of science, a revised periodic table is proposed.
基金Supported by the Project of Knowledge Innovation Program of the Chinese Academy of Sciences under Grant No. KJCX2.YW.W10Sistema Nacional de Investigadores+8 种基金CONACyT grant 46614-Fthe University of Adelaide and the Australian Research Council through Grant No. FL0992247Coordinación de la Investigación Científica (UMSNH) under Grant 4.10the U. S. Department of Energy, Office of Nuclear Physics, Grant No. DE-AC02-06CH11357Fundao de Amparo Pesquisa do Estado de So Paulo, Grant Nos. 2009/51296-1 and 2010/05772-3the National Natural Science Foundation of China under Grant Nos. 10425521, 10675002, 10705002, 10935001 and 11075052the Major State Basic Research Development Program, under Grant No. G2007CB815000Forschungszentrum Jülich GmbHthe U. S.National Science Foundation under Grant No. PHY-0903991, in conjunction with a CONACyT Mexico-USA Collaboration Grant
文摘We survey contemporary studies of hadrons and strongly interacting quarks using QCD's Dyson-Schwinger equations, addressing the following aspects: confinement and dynamical chiral symmetry breaking; the hadron spectrum; hadron elastic and transition form factors, from small-to large-Q2; parton distribution functions; the physics of hadrons containing one or more heavy quarks; and properties of the quark gluon plasma.
基金Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030008)Science and Technology Program of Guangzhou(No.2019050001)National Science Foundation of China(Nos.12347130 and 11935007).
文摘The medium-temperature T dependence of the jet transport coefficient̂q was studied via the nuclear modification factor RAA(p_(T))and elliptical flow parameter v_(2)(p_(T))for large transverse momentum p_(T) hadrons in high-energy nucleus-nucleus collisions.Within a next-to-leading-order perturbative QCD parton model for hard scatterings with modified fragmentation functions due to jet quenching controlled by q,we check the suppression and azimuthal anisotropy for large p_(T) hadrons,and extract q by global fits to RAA(pT)and v_(2)(pT)data in A+A collisions at RHIC and LHC,respectively.The numerical results from the best fits show that q∕T^(3) goes down with local medium-temperature T in the parton jet trajectory.Compared with the case of a constant q∕T^(3),the going-down T dependence of q∕T^(3) makes a hard parton jet to lose more energy near T_(c) and therefore strengthens the azimuthal anisotropy for large pT hadrons.As a result,v_(2)(p_(T))for large pT hadrons was enhanced by approximately 10%to better fit the data at RHIC/LHC.Considering the first-order phase transition from QGP to the hadron phase and the additional energy loss in the hadron phase,v_(2)(p_(T))is again enhanced by 5-10%at RHIC/LHC.
基金Supported in part by the National Nature Science Foundations of China (12335002)the Fundamental Research Funds for the Central Universities。
文摘The attractive interaction between J/ψandψ(3770)has to be strong enough if X(6900)is of the molecule type.We argue that sinceψ(3770)decays predominantly into a DD^(¯)pair,the interactions between J/ψandψ(3770)may be significantly enhanced owing to the three point DD^(¯)loop diagram.The enhancement originates from the anomalous threshold located at t=−1.288 GeV^(2),whose effect propagates into the s-channel partial wave amplitude in the vicinity of √s≃6.94 GeV.This effect may be helpful in the formation of the X(6900)peak.
基金the Center for Theoretical Physics (CTP) at the British University in Egypt (BUE) for its continuous support,both financially and scientifically,for this work。
文摘In this study,we conducted a search for dark matter using a part of the data recorded by the CMS experiment during run-I of the LHC in 2012 with a center of mass energy of 8 TeV and an integrated luminosity of 11.6 fb−1.These data were gathered from the CMS open data.Dark matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.Thus,the search was conducted in the dimuon plus large missing transverse momentum channel.One benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the CMS open data.No evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.
基金Supported by the National Natural Science Foundation of China(12205002)partly supported by the the Natural Science Foundation of Anhui Province(2108085MA20)
文摘The role of the triangle mechanism in the decay processes B_(0)→J/ψK^(0)f_(0)→J/ψK^(0)π^(+)π^(-)and B_(0)→J/ψK^(0)a_(0)→J/ψK^(0)π^(0)ηis probed.In these processes,the triangle singularity appears from the decay of B_(0)intoJ/ψ∅K^(0),and then,∅decays intoK^(0)K^(0)andK^(0)K^(0)merged into f_(0)or a_(0),which finally decay intoπ^(+)π^(-)andπ^(0)η,respectively.We find that this mechanism leads to a triangle singularity around M_(inv)(K^(0)f_(0)(a_(0)))≈1520 MeV and gives sizable branching fractions Br(B_(0)→J/ψK^(0)f_(0)→J/ψK^(0)π^(+)π^(-))=7.67×10^(-7)and Br(B_(0)→J/ψK^(0)a_(0)→J/ψK^(0)π^(0)η)=1.42×10^(-7).This investigation can help us obtain the information of the scalar mesonf_(0)(980)or a_(0)(980).
文摘The practice of using the direct ionization radiation (electrons, protons, antiprotons, pions, ions, etc) or of the indirect ionization radiation (photons, neutrons, etc) in economy and social life has led to the introduction of the absorbed dose magnitude (ICRU 1953) defined as the energy absorbed per mass unit of the irradiated substance. This is a fundamental magnitude valid for any type of ionizing radiation, any irradiated material and any radiation energy. In case of clinical hadron beams generated by conventional accelerators or those controlled by lasers, IAEA TRS 398 recommends the absorbed dose to water. This may be determined employing the calorimeter method with water or graphite, chemical method, fluence based measurements as Faraday cups or activation measurements, and the ionization chamber method. In this paper the selected method was the thimble air filled ionization chamber method for determination of absorbed dose to water.
文摘Previously the 5D homogeneous space-time metric was introduced with explicitly given projection operators in matrix form which map the 5D space-time manifold into a Lorentzian space-time. Based on this projection model, vector field and spinor solutions are found to be expressible in terms of SU(2)xL and SU(3)xL, where L is the 4D Lorentz space-time group. The spinor solutions give the SU(2) leptonic states arising from space-time projection, whereas the SU(3) representation arises from conformal projection and gives the quarks, and due to gauge requirement leads to mesons and baryons. This process of mapping the 5D space-time manifold into the 4D space-time is at the basis of an analysis of the recent CERN experimental results, the presence of neutrino oscillations and the observed 125 GeV resonance in the p-p collisions, respectively. In fact, it is found that the spinor solution contains an oscillating phase, and the 125 GeV resonance is shown to be predictable, thereby 1) eliminating the need to introduce a Higgs vacuum, and 2) can be shown possibly to be an indicator for a missing heavy baryon octet.
基金Supported in part by the National Natural Science Foundation of China(NSFC)(12235016,12221005,11725523,11735007,12275108)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB34030000,XDPB15)+1 种基金the start-up funding from University of Chinese Academy of Sciences(UCAS)the Fundamental Research Funds for the Central Universities。
文摘The simplest version of the dynamical holographic QCD model is described by adding the KKSS model action on a dilaton-graviton coupled background,in which the AdS5 metric is deformed by the gluon condensation and further deformed by the chiral condensation.In this framework,both the chiral symmetry breaking and linear confinement can be realized.The light-flavor hadron spectra and the pion form factor were investigated,but it was difficult to reconcile the light-flavor hadron spectra and pion form factor.By considering the anomalous 5-dimension mass correction of the scalar field from QCD running coupling,it is found that the light flavor hadron spectra and pion form factor can be described well simultaneously.In particular,the ground state and lower excitation states of the scalar,pseudo scalar,and axial vector meson spectra are improved.However,the vector meson spectra are not sensitive to the anomalous 5-dimension mass correction of the scalar field.
基金Supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB34030300,XDPB15)the National Key Research and Development Program of China(2020YFA0406400)+1 种基金the National Natural Science Foundation of China(NNSFC)under Grants(11935017,12070131001)(CRC 110 by DFG and NNSFC)supported in part by a NSFC-DFG joint grant(12061131006 and SCHA458/22)。
文摘Glueballs are investigated through gluonic operators on two N_(f)=2+1RBC/UKQCD gauge ensembles at the physical pion mass.The statistical errors of glueball correlation functions are considerably reduced through the cluster decomposition error reduction(CDER)method.The Bethe-Salpeter wave functions are obtained for the scalar,tensor,and pseudoscalar glueballs by using spatially extended glueball operators defined through the gauge potential A_(μ)(x)in the Coulomb gauge.These wave functions exhibit similar features of non-relativistic two-gluon systems and are used to optimize the signals of the related correlation functions at the early time regions,where the ground state masses are extracted.These masses are close to those from the quenched approximation and indicate the possible existence of glueballs at the physical point.The resonance feature of glueballs and the mixing with conventional mesons and multi-hadron systems should be considered in a more systematic lattice study.
基金Supported in part by National Key R&D Program of China(Grant Nos.2020YFA0406400,2020YFA0406300)National Natural Science Foundation of China(NSFC)(Grant Nos.11635010,11735014,11805086,11835012,11935015,11935016,11935018,11961141012,12022510,12025502,12035009,12035013,12192260,12192261,12192262,12192263,12192264,12192265)+18 种基金the Chinese Academy of Sciences(CAS)Large-Scale Scientific Facility ProgramJoint Large-Scale Scientific Facility Funds of the NSFC and CAS(Grant No.U1832207)the CAS Center for Excellence in Particle Physics(CCEPP)100 Talents Program of CASFundamental Research Funds for the Central Universities,Lanzhou University,University of Chinese Academy of SciencesThe Institute of Nuclear and Particle Physics(INPAC)and Shanghai Key Laboratory for Particle Physics and CosmologyERC(Grant No.758462)European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement(Grant No.894790)German Research Foundation DFG(Grant No.443159800),Collaborative Research Center CRC 1044,GRK 2149Istituto Nazionale di Fisica Nucleare,ItalyMinistry of Development of Turkey(Grant No.DPT2006K-120470)National Science and Technology fundNational Science Research and Innovation Fund(NSRF)via the Program Management Unit for Human Resources&Institutional Development,Research and Innovation(Grant No.B16F640076)Olle Engkvist Foundation(Grant No.200-0605)STFC(United Kingdom)Suranaree University of Technology(SUT),Thailand Science Research and Innovation(TSRI),and National Science Research and Innovation Fund(NSRF)(Grant No.160355)The Royal Society,UK(Grant Nos.DH140054,DH160214)The Swedish Research CouncilU.S.Department of Energy(Grant No.DE-FG02-05ER41374)。
文摘We report a search for a heavier partner of the recently observed Z_(cs)(3985)^(-) state,denoted as Z_(cs)^('-),in the process e^(+)e^(−)→K^(+)D_(s)^(∗−) D^(∗0 )+ c.c.,based on e^(*)e^(-)collision data collected at the center-of-mass energies of √s=4.661,4.682 and 4.699 GeV with the BESIII detector.The Z_(cs)^('-) is of interest as it is expected to be a candidate for a hidden-charm and open-strange tetraquark.A partial-reconstruction technique is used to isolate K^(+)recoil-mass spectra,which are probed for a potential contribution from Z_(cs)^('-)→D_(s)^(∗−) D^(∗0 )+ c.c.We find an excess of Z_(cs)^('-)→D_(s)^(*-)-D^(*0)(c.c.)candidates with a significance of 2.1o,after considering systematic uncertainties,at a mass of(4123.5±0.7_(sat)±4.7_(syst.))MeV/c^(2).As the data set is limited in size,the upper limits are evaluated at the 90%confidence level on the product of the Born cross sections(σ^(Borm))and the branching fraction(B)of Z_(cs)^('-)→D_(s)^(*-)-D^(*0),under different assumptions of the Z_(cs)^('-) mass from 4.120 to 4.140 MeV and of the width from 10 to 50 MeV at the three center-of-mass energies.The upper limits of σ^(Born).B are found to be at the level of O(1)pb at each energy.Larger data samples are needed to confirm the Z_(cs)^('-) state and clarify its nature in the coming years.
文摘Accessing a full image of the inner content of hadrons represents a central endeavour of modern particle physics,with the main scientific motivation to investigate the strong interaction binding the visible matter.On the one hand,the structure of known exotic candidates is a fundamental open issue addressed widely by scientists.On the other hand,looking for new states of exotic nature is a central component for theoretical and experimental efforts from electron-positron machine and electron accelerator with fixed target to heavy ion and electron-ion colliders.In this article we present a succinct short overview of the attempt to search for exotic narrow N∗and Z states containing light quarks only or also charm,and its connotation for bottom regions(the latter two are also known as Pc(Zc)and Pb(Zb)states,respectively in the literature).We address the effort of searching for exotic narrow N∗and Z states in light quark sector.We focus on recent progress in searching for signal of Pc and Zc states photoproduction and its implication into the Pb and Zb photoproduction and their decay properties.We also discuss future perspectives for the field in electron-ion colliders,a good place to disentangle the nature of some of these states and investigate some other enlightening topics including QCD trace anomaly and quarkonium-nucleon scattering length.
基金Supported by Guangdong Major Project of Basic and Applied Basic Research(2020B0301030008)the National Natural Science Foundation of China(12105107)Science and Technology Program of Guangzhou(2019050001)。
文摘The yields of X_(cscs)with its two possible configurations,i.e.,the hadronic molecular state and tetraquark state,for Pb-Pb collisions at√sNN=5.02 TeV is studied.A volume effect is found from the centrality distribution of X_(cscs),which could help to distinguish the inner structure of X_(cscs).We also show the rapidity and the transverse momentum distributions of X_(cscs) production as well as its elliptic flow coefficient as a function of the transverse momentum.
基金the Fundamental Research Funds for the Central Universities(FRF-BR-19-001A)the National Natural Science Foundation of China(11975028,11974043)。
文摘The inclusion of theρ−ωmixing effect is essential for a precise description of the pion electromagnetic form factor in the e+e−→π+π−process,which quantifies the two-pion contribution to the anomalous magnetic moment of muon aμ.In this study,we analyze the momentum dependence ofρ−ωmixing by considering loop contributions at the next-to-leading order in 1/NC expansion within the framework of resonance chiral theory.We revisit a previous study[Y.H.Chen,D.L.Yao,and H.Q.Zheng,Commun.Theor.Phys.69,1(2018)]and consider the contribution arising from the kaon mass splitting in the kaon loops and latest experimental data.We perform two types of fits(with momentum-independent or momentum-dependentρ−ωmixing amplitude)to describe e+e−→π+π−andτ→ντ2πdata within the energy region of 600−900 MeV and decay width ofω→π+π−.Furthermore,we compare their results.Our findings indicate that the momentum-independent and momentum-dependentρ−ωmixing schemes provide appropriate descriptions of the data.However,the momentum-dependent scheme exhibits greater self-consistency,considering the reasonable imaginary part of the mixing matrix elementΠρωobtained.Regarding the contribution to the anomalous magnetic moment of the muon,aππμ|[0.6,0.9]GeV,the results obtained from the fits considering the momentum-dependentρ−ωmixing amplitude are in good agreement with those obtained without incorporating the momentum dependence ofρ−ωmixing,within the margin of errors.Furthermore,based on the fitted values of the relevant parameters,we observe that the decay width ofω→π+π−is predominantly influenced by theρ−ωmixing effect.
文摘This study investigates the prospect of discovering strongly interacting gluinos in different multi-lepton channels with lepton multiplicities greater than or equal to 2 at LHC RUN-Ⅲ,considering several pMSSM scenarios.The effectiveness of the multivariate analysis(MVA) method with the boosted decision tree(BDT) algorithm is explored to obtain a better significance for different models.Promising results are obtained for the 3-lepton channels,indicating that the use of MVA methods can improve the sensitivity of the search for gluinos at LHC RUN-Ⅲ.The study probes the multi-lepton signatures arising from gluinos via intermediate eweakinos and sleptons at an early stage of the LHC RUN-Ⅲ.The heavier eweakinos can give rise to three or four lepton signals,in which the squark hierarchy between the L and R types plays a crucial role.The study considers two sets of benchmark points that satisfy all the collider constraints obtained from the LHC RUN-Ⅱ data.Moreover,these sets of benchmark points are mostly consistent with WMAP/PLANCK data and the muon(g-2) constraint.The corresponding results from the MVA technique demonstrate that,even for an integrated luminosity of 270 fb-1,the 5 σ discovery prospect of3l+jets+ETfor Mg=1.8 TeV in the wino type model is promising.The study also presents various other models that may emerge at the early stage of LHC RUN-Ⅲ.Wino type models in the scenario where left squarks are light and right squarks are heavy exhibit the best prospect of discovering gluinos in multi-lepton channels in the LHC RUN-Ⅲ experiment.The findings of this study provide crucial insights into the potential discovery of gluinos in multi-lepton channels.
