The X(3872)is theoretically predicted to have a spin-0 partner state denoted as X_(0).Assuming the X_(0)as a molecular bound state,we calculate the decay widths of X_(0)→VV and X_(0)→PP(V and P stand for light vecto...The X(3872)is theoretically predicted to have a spin-0 partner state denoted as X_(0).Assuming the X_(0)as a molecular bound state,we calculate the decay widths of X_(0)→VV and X_(0)→PP(V and P stand for light vector and pseudoscalar mesons,respectively)via intermediate charmed meson loops.Three different configurations of the X_(0),i.e.,pure neutral components(θ=0),isospin singlet(θ=π/4),and pure charged components(θ=π/2),are investigated.Within a commonly accepted range of the model parameterα,the predicted decay widths of X_(0)→VV are on the order of a few hundred keV,while the decay widths of X_(0)→PP can reach several MeV.The X_(0)→ρρandππhave larger decay rates.The relative width ratios between the channels are nearly model-independent.Moreover,among those channels only with isovector or isoscalar mesons,the relevant ratios are also independent of the phase angle.The predicted ratios are helpful for searching the X_(0)in the future experiments at BESIII and Belle II.展开更多
The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used ...The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used and the design of the detector geometry.This paper presents the optimized design of the hadronic calorimeter(HCAL)used in the DarkSHINE experiment,which is studied using a GEANT4-based simulation framework.The geometry is optimized by comparing a traditional design with uniform absorbers to one that uses different thicknesses at different locations on the detector,which enhances the efficiency of vetoing low-energy neutrons at the sub-GeV level.The overall size and total amount of material used in the HCAL are optimized to be lower,owing to the load and budget requirements,whereas the overall performance is studied to satisfy the physical objectives.展开更多
The spectrum of hadronic molecules composed of heavy-antiheavy charmed hadrons has been obtained in our previous work.The potentials are constants at the leading order,which are estimated from resonance saturation.The...The spectrum of hadronic molecules composed of heavy-antiheavy charmed hadrons has been obtained in our previous work.The potentials are constants at the leading order,which are estimated from resonance saturation.The experimental candidates of hadronic molecules,say X(3872),Y(4260),three P_(c)states and P_(cs)(4459),fit the spectrum well.The success in describing the pattern of heavy-antiheavy hadronic molecules stimulates us to give more predictions for the heavy-heavy cases,which are less discussed in literature than the heavy-antiheavy ones.Given that the heavy-antiheavy hadronic molecules,several of which have strong experimental evidence,emerge from the dominant constant interaction from resonance saturation,we find that the existence of many heavy-heavy hadronic molecules is natural.Among these predicted heavy-heavy states we highlight the DD;molecule and the D^(*)∑_(c)^(*)molecules,which are the partners of the famous X(3872)and Pc states.Quite recently,LHCb collaboration reported a doubly charmed tetraquark state,T_(cc),which is in line with our results for the DD^(*)molecule.With the first experimental signal of this new kind of exotic states,the upcoming update of the LHCb experiment as well as other experiments will provide more chances of observing the heavy-heavy hadronic molecules.展开更多
After examining Feynman diagrams corresponding to the ■, ■, ■, and ■ hadronic molecular states, we propose a possible binding mechanism induced by shared light quarks. This mechanism is similar to the covalent bon...After examining Feynman diagrams corresponding to the ■, ■, ■, and ■ hadronic molecular states, we propose a possible binding mechanism induced by shared light quarks. This mechanism is similar to the covalent bond in chemical molecules induced by shared electrons. We use the method of QCD sum rules to calculate its corresponding light-quark-exchange diagrams, and the obtained results indicate a model-independent hypothesis: the light-quark-exchange interaction is attractive when the shared light quarks are totally antisymmetric so they obey the Pauli principle. We build a toy model with four parameters to formulize this picture and estimate binding energies of some possibly-existing covalent hadronic molecules. A unique feature of this picture is that the binding energies of the(I)JP=(0)1+■ hadronic molecules are much larger than those of the (I)JP=(0)1+■ ones, while the(I)JP=(1/2)1/2+■ hadronic molecules have similar binding energies.展开更多
The influences of hyperon-hyperon interaction on the overall properties of hadronic star are investigated in the framework of relativistic mean field （RMF） theory. For certain hyperon coupling, the weaker hyperon-hy...The influences of hyperon-hyperon interaction on the overall properties of hadronic star are investigated in the framework of relativistic mean field （RMF） theory. For certain hyperon coupling, the weaker hyperon-hyperon interaction can lead to the heavier hadronic star, which accords with the observation of heavy neutron star in X-ray binaries. We find that the threshold densities of the hyperons with larger masses are brought to a lower values with the increase of the hyperon-hyperon interaction. The possibility of the existence of hyperon star is checked with the consideration of hyperon-hyperon interaction.展开更多
The internal structure of the charm-strange mesons D_(s0)^(*)(2317)and D_(s1)(2460)are the subject of intensive studies.Their widths are small because they decay dominantly through isospinbreaking hadronic channels D_...The internal structure of the charm-strange mesons D_(s0)^(*)(2317)and D_(s1)(2460)are the subject of intensive studies.Their widths are small because they decay dominantly through isospinbreaking hadronic channels D_(s0)^(*)(2317)^(+)→D_(s)^(+)π^(0) and D _(s1)(2460)^(+)→D_(s)^(*+)π^(0).The D_(s1)(2460)can also decay into the hadronic final states D_(s)^(+)ππ,conserving isospin.In that case there is,however,a strong suppression from phase space.We study the transition D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)in the scenario that the D_(s1)(2460)is a D^(*)K hadronic molecule.The ππ final state interaction is taken into account through dispersion relations.We find that the ratio of the partial widths of the Γ(D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)) / Γ(D_(s1)(2460)^(+)→D_(s)^(*+)π^(0))obtained in the molecular picture is consistent with the existing experimental measurement.More interestingly,we demonstrate that theπ+π−invariant mass distribution shows a double bump structure,which can be used to disentangle the hadronic molecular picture from the compact state picture for the D_(s1)(2460)^(+).Predictions on the B_(s1)^(0)→B_(s)^(0)π^(+)π^(-)are also made.展开更多
The baryon spectrum and the baryon couplings are two of the most important issues in hadronic physics andthey are attracting much attention. Both on the experimental and theoretical sides, the nucleon excited states b...The baryon spectrum and the baryon couplings are two of the most important issues in hadronic physics andthey are attracting much attention. Both on the experimental and theoretical sides, the nucleon excited states below2.0 GeV have been extensively studied[1]. However, the current information for the properties of states around orabove 2.0 GeV is scarce. On the other hand, in this energy region, many theoretical approaches have predictedmissing N states, which have not been so far observed. Hence, the study of the possible role played by the 2.0GeV region nucleon resonances in the available accurate data is timely and could shed light into the complicateddynamics that governs the high excited nucleon spectrum.展开更多
Proton knockout reactions are a widely used tool to study nuclear ground-state distributions. While the interpretation of traditional experiments in direct kinematics has to account for initial and final state interac...Proton knockout reactions are a widely used tool to study nuclear ground-state distributions. While the interpretation of traditional experiments in direct kinematics has to account for initial and final state interactions, experiments in inverse kinematics can overcome such limitations. We discuss results of an experiment at the BM@N setup at JINR using a <sup>12</sup>C beam at 48 GeV/c to study quasi-elastic scattering reactions, single proton distributions, and short-range correlated nucleon-nucleon pairs. The inverse kinematics allows for the direct measurement of the nucleon-nucleon pair center-of-mass motion and provides first experimental evidence for scale separation of such pairs. Based on these results, we will in the future study neutron-rich nuclei in inverse kinematics in the context of short-range correlations and neutron stars.展开更多
The physical picture of coexistence of both hadronic and QGP phases is given by Friedberg and T.D. Lee's nontopology soliton model. The transport properties of quark in color space and spin space in a system of tw...The physical picture of coexistence of both hadronic and QGP phases is given by Friedberg and T.D. Lee's nontopology soliton model. The transport properties of quark in color space and spin space in a system of two-phase coexistence are investigated from both quantum and classical theories.展开更多
The hadronic vacuum polarization correction to the photon propagator is found by using the Dubnicka-Meshcheryakov parametrization of the pion form factor and new experimental data on the e^(+)e^(-)→hadrons anniKilati...The hadronic vacuum polarization correction to the photon propagator is found by using the Dubnicka-Meshcheryakov parametrization of the pion form factor and new experimental data on the e^(+)e^(-)→hadrons anniKilation cross section.展开更多
Elliptic flow v2 is considered as a probe to study partonic collectivity,and the measurement v2/εcan be used to describe the hydro behavior of the colliding system.We study the the effect of the hadronic process on t...Elliptic flow v2 is considered as a probe to study partonic collectivity,and the measurement v2/εcan be used to describe the hydro behavior of the colliding system.We study the the effect of the hadronic process on the momentum anisotropy parameter v2 in a multiphase transport model.It is found that hadronic rescattering will depress the v2 signal built up at the partonic phase.A similar mass hierarchy is observed in the model as in the experiment at RHIC.We find that different particle species will approach the same ideal hydro limit if the hadronic process is excluded.展开更多
The cross section for three-jet events via the e^(+)e^(−)→hadronic Rindler horizon→qqg process is compared to experimental data from the OPAL collaboration.It is found that the model is consistent with the QCD exper...The cross section for three-jet events via the e^(+)e^(−)→hadronic Rindler horizon→qqg process is compared to experimental data from the OPAL collaboration.It is found that the model is consistent with the QCD experiments.展开更多
A soft-hard two-component approach to the description of high energy hadronic interactions is proposed.It shows the important role of parton hard scattering in explanation of the chief characteristics of high energy h...A soft-hard two-component approach to the description of high energy hadronic interactions is proposed.It shows the important role of parton hard scattering in explanation of the chief characteristics of high energy hadronic interactions.展开更多
Based on the extended hadronic transport model,we investigate the incompressibility of dense hadronic matter formed in relativistic Au+Au heavy-ion collisions at√SNN=3 GeV.By comparing various experimental observ-abl...Based on the extended hadronic transport model,we investigate the incompressibility of dense hadronic matter formed in relativistic Au+Au heavy-ion collisions at√SNN=3 GeV.By comparing various experimental observ-ables,such as proton directed ow,production yields of strange hadronsϕ,K−as well as their ratioϕ/K−and proton high-order cumulants with our model calculations,we nd that hadronic interactions play a dominant role in these collisions.展开更多
Numerous candidates for exotic hadrons have been detected experimentally in the past two decades,predominantly near the threshold of a pair of hadrons.This study aims to investigate the overall behavior of nearthresho...Numerous candidates for exotic hadrons have been detected experimentally in the past two decades,predominantly near the threshold of a pair of hadrons.This study aims to investigate the overall behavior of nearthreshold line shapes in invariant mass distributions.It is noteworthy that the threshold cusp might manifest as a peak only in channels with attractive interaction.The assertion is made that there should be near-threshold structures for any heavy-quark and heavy-antiquark hadron pairs exhibiting attractive interaction at the threshold,as observed in the invariant mass distribution of heavy quarkonium and light hadrons that couple to the open-flavor hadron pair.Furthermore,we have conducted an analysis of potential hadronic molecules comprising pairs of heavy hadrons,utilizing the Bethe-Salpeter equation with constant interactions derived from the one-boson-exchange model.Observed candidates for these hadronic molecules are in good agreement with our predicted spectrum.展开更多
We present a concise review of the vector charmonium state ψ(4230), which was originally labelled as Y(4260)in the literature. As one of the earliest candidates for a quantum chromodynamics exotic states, its interpr...We present a concise review of the vector charmonium state ψ(4230), which was originally labelled as Y(4260)in the literature. As one of the earliest candidates for a quantum chromodynamics exotic states, its interpretation has initiated various ideas about possible manifestations of non-perturbative mechanisms in the charmonium mass regime. In this short article we briefly review the experimental status of ψ(4230) and discuss possible theoretical interpretations. We will focus on four broadly investigated scenarios, i.e., tetraquark, hybrid, hadro-quarkonium,and hadronic molecule, and highlight the key issues based on these approaches. Crucial experimental observables,e.g., mass position, lineshapes, di-lepton decay width Γ_(ee), production rates in B meson decays, dominant hadronic decay patterns, and the potential 1^(-+)and 0^(--)exotic partners, are assessed, which can provide crucial structure information for understanding this mysterious state.展开更多
The observations of fully-charm tetraquark states in the LHCb,CMS,and ATLAS experiments suggested the existence of hadronic molecules of two-charmonium states,which may also imply bound states in the threecharmonium s...The observations of fully-charm tetraquark states in the LHCb,CMS,and ATLAS experiments suggested the existence of hadronic molecules of two-charmonium states,which may also imply bound states in the threecharmonium systems.In this work,we study the possible bound states in the triple-ηcand triple-J/ψsystems with J^(PC)=0^(-+)and 1^(--),respectively.In quantum chromodynamics sum rules,we calculate the two-point correlation functions and spectral functions up to the dimension-four gluon condensate.We use the iterative dispersion relation approach to deal with the five-loop banana integrals,which significantly improves computational efficiency.Our results show that the masses of triple-ηcand triple-J/ψstates lie below the corresponding mass thresholds,supporting the existence of such three-body bound states.展开更多
Spin alignments of vector mesons and hyperons in relativistic heavy-ion collisions have been proposed as signals of global polarization.The STAR experiment first observed the ∧ polarization.Recently,the ALICE collabo...Spin alignments of vector mesons and hyperons in relativistic heavy-ion collisions have been proposed as signals of global polarization.The STAR experiment first observed the ∧ polarization.Recently,the ALICE collaboration measured the transverse momentum {PT) and the collision centrality dependence of K*,and Φ spin alignments during Pb-Pb collisions at 1/2sNN=2.76 TeV.A large signal is observed in the low pT region of mid-central collisions for K*,while the signal is much smaller for Φ,and these have not been understood yet.Since vector mesons have different lifetimes and their decay products have different scattering cross sections,they suffer from different hadronic effects.In this paper,we study the effect of hadronic interactions on the spin alignment of K*,Φ,and p mesons in relativistic heavy-ion collisions with a multi-phase transport model.We find that hadronic scatterings lead to a deviation of the observed spin alignment matrix element p00 away from the true value for p and K*mesons(with a bigger effect on p) while the effect is negligible for the Φ meson.The effect depends on the kinematic acceptance:the observed p00 value is lower than the true value when the pseudorapidity(η) coverage is small,while there is little effect when the η coverage is large.Hence,this study provides valuable information to understand the vector meson spin alignment signals observed during the experiments.展开更多
In this paper, we studied the development of hadronic shower in an electromagnetic calorimeter of Alpha Magnetic Spectrometer Ⅱ. Two parametrized empirical formulae were proposed to describe the hadronic shower shape...In this paper, we studied the development of hadronic shower in an electromagnetic calorimeter of Alpha Magnetic Spectrometer Ⅱ. Two parametrized empirical formulae were proposed to describe the hadronic shower shape in calorimeter. Using 100 GeV proton beam incident on the center of the ECAL, detailed plots of lateral and longitudinal hadronic shower behavior were given and we found the formulae can describe the development of the hadronic shower with the test beam data. The possible application of the parametrized formulae including e±-π± discrimination and tau jet reconstruction was discussed.展开更多
In high-temperature quark-gluon plasma and its subsequent hadronic matter created in a high-energy nucleus-nucleus collision, the quark-antiquark potential depends on the temperature. The temperature-dependent potenti...In high-temperature quark-gluon plasma and its subsequent hadronic matter created in a high-energy nucleus-nucleus collision, the quark-antiquark potential depends on the temperature. The temperature-dependent potential is expected to be derived from the free energy obtained in lattice gauge theory calculations. This requires one to study the relationship between the quark-antiquark potential and the quark-antiquark free energy. When the system＇s temperature is above the critical temperature, the potential of a heavy quark and a heavy antiquark almost equals the free energy, but the potential of a light quark and a light antiquark, of a heavy quark and a light antiquark and of a light quark and a heavy antiquark is substantially larger than the free energy. When the system＇s temperature is below the critical temperature, the quark-antiquark free energy can be taken as the quark-antiquark potential. This allows one to apply the quark-antiquark free energy to study hadron properties and hadron-hadron reactions in hadronic matter.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12475081 and 12105153)the Natural Science Foundation of Shandong Province(Grant Nos.ZR2021MA082 and ZR2022ZD26)Taishan Scholar Project of Shandong Province(Grant No.tsqn202103062).
文摘The X(3872)is theoretically predicted to have a spin-0 partner state denoted as X_(0).Assuming the X_(0)as a molecular bound state,we calculate the decay widths of X_(0)→VV and X_(0)→PP(V and P stand for light vector and pseudoscalar mesons,respectively)via intermediate charmed meson loops.Three different configurations of the X_(0),i.e.,pure neutral components(θ=0),isospin singlet(θ=π/4),and pure charged components(θ=π/2),are investigated.Within a commonly accepted range of the model parameterα,the predicted decay widths of X_(0)→VV are on the order of a few hundred keV,while the decay widths of X_(0)→PP can reach several MeV.The X_(0)→ρρandππhave larger decay rates.The relative width ratios between the channels are nearly model-independent.Moreover,among those channels only with isovector or isoscalar mesons,the relevant ratios are also independent of the phase angle.The predicted ratios are helpful for searching the X_(0)in the future experiments at BESIII and Belle II.
基金supported by National Key R&D Program of China(Nos.2023YFA1606904 and 2023YFA1606900)National Natural Science Foundation of China(No.12150006)Shanghai Pilot Program for Basic Research-Shanghai Jiao Tong University(No.21TQ1400209).
文摘The sensitivity of the dark photon search through invisible decay final states in low-background experiments relies sig-nificantly on the neutron and muon veto efficiencies,which depend on the amount of material used and the design of the detector geometry.This paper presents the optimized design of the hadronic calorimeter(HCAL)used in the DarkSHINE experiment,which is studied using a GEANT4-based simulation framework.The geometry is optimized by comparing a traditional design with uniform absorbers to one that uses different thicknesses at different locations on the detector,which enhances the efficiency of vetoing low-energy neutrons at the sub-GeV level.The overall size and total amount of material used in the HCAL are optimized to be lower,owing to the load and budget requirements,whereas the overall performance is studied to satisfy the physical objectives.
基金supported in part by the Chinese Academy of Sciences(CAS)under Grant No.XDPB15,No.XDB34030000,No.QYZDB-SSWSYS013by the National Natural Science Foundation of China(NSFC)under Grant No.11835015,No.12047503,No.11961141012by the NSFC and the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)through funds provided to the Sino-German Collaborative Research Center‘Symmetries and the Emergence of Structure in QCD’(NSFC Grant No.12070131001,DFG Project-ID 196253076—TRR110)。
文摘The spectrum of hadronic molecules composed of heavy-antiheavy charmed hadrons has been obtained in our previous work.The potentials are constants at the leading order,which are estimated from resonance saturation.The experimental candidates of hadronic molecules,say X(3872),Y(4260),three P_(c)states and P_(cs)(4459),fit the spectrum well.The success in describing the pattern of heavy-antiheavy hadronic molecules stimulates us to give more predictions for the heavy-heavy cases,which are less discussed in literature than the heavy-antiheavy ones.Given that the heavy-antiheavy hadronic molecules,several of which have strong experimental evidence,emerge from the dominant constant interaction from resonance saturation,we find that the existence of many heavy-heavy hadronic molecules is natural.Among these predicted heavy-heavy states we highlight the DD;molecule and the D^(*)∑_(c)^(*)molecules,which are the partners of the famous X(3872)and Pc states.Quite recently,LHCb collaboration reported a doubly charmed tetraquark state,T_(cc),which is in line with our results for the DD^(*)molecule.With the first experimental signal of this new kind of exotic states,the upcoming update of the LHCb experiment as well as other experiments will provide more chances of observing the heavy-heavy hadronic molecules.
基金the National Natural Science Foundation of China under Grants No.11722540 and No.12075019the Jiangsu Provincial Double-Innovation Program under Grant No.JSSCRC2021488the Fundamental Research Funds for the Central Universities
文摘After examining Feynman diagrams corresponding to the ■, ■, ■, and ■ hadronic molecular states, we propose a possible binding mechanism induced by shared light quarks. This mechanism is similar to the covalent bond in chemical molecules induced by shared electrons. We use the method of QCD sum rules to calculate its corresponding light-quark-exchange diagrams, and the obtained results indicate a model-independent hypothesis: the light-quark-exchange interaction is attractive when the shared light quarks are totally antisymmetric so they obey the Pauli principle. We build a toy model with four parameters to formulize this picture and estimate binding energies of some possibly-existing covalent hadronic molecules. A unique feature of this picture is that the binding energies of the(I)JP=(0)1+■ hadronic molecules are much larger than those of the (I)JP=(0)1+■ ones, while the(I)JP=(1/2)1/2+■ hadronic molecules have similar binding energies.
文摘The influences of hyperon-hyperon interaction on the overall properties of hadronic star are investigated in the framework of relativistic mean field （RMF） theory. For certain hyperon coupling, the weaker hyperon-hyperon interaction can lead to the heavier hadronic star, which accords with the observation of heavy neutron star in X-ray binaries. We find that the threshold densities of the hyperons with larger masses are brought to a lower values with the increase of the hyperon-hyperon interaction. The possibility of the existence of hyperon star is checked with the consideration of hyperon-hyperon interaction.
基金supported in part by the National Natural Science Foundation of China(NSFC)the Deutsche Forschungsgemeinschaft(DFG)through the funds provided to the Sino-German Collaborative Research Center TRR110‘Symmetries and the Emergence of Structure in QCD’(NSFC Grant No.12070131001,DFG Project-ID 196253076)+3 种基金the Chinese Academy of Sciences(CAS)under Grant No.XDB34030000the NSFC under Grants Nos.12125507,11835015,and 12047503CAS through the President’s International Fellowship Initiative(PIFI)(Grant No.2018DM0034)the Volkswagen Stiftung(Grant No.93562)
文摘The internal structure of the charm-strange mesons D_(s0)^(*)(2317)and D_(s1)(2460)are the subject of intensive studies.Their widths are small because they decay dominantly through isospinbreaking hadronic channels D_(s0)^(*)(2317)^(+)→D_(s)^(+)π^(0) and D _(s1)(2460)^(+)→D_(s)^(*+)π^(0).The D_(s1)(2460)can also decay into the hadronic final states D_(s)^(+)ππ,conserving isospin.In that case there is,however,a strong suppression from phase space.We study the transition D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)in the scenario that the D_(s1)(2460)is a D^(*)K hadronic molecule.The ππ final state interaction is taken into account through dispersion relations.We find that the ratio of the partial widths of the Γ(D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)) / Γ(D_(s1)(2460)^(+)→D_(s)^(*+)π^(0))obtained in the molecular picture is consistent with the existing experimental measurement.More interestingly,we demonstrate that theπ+π−invariant mass distribution shows a double bump structure,which can be used to disentangle the hadronic molecular picture from the compact state picture for the D_(s1)(2460)^(+).Predictions on the B_(s1)^(0)→B_(s)^(0)π^(+)π^(-)are also made.
文摘The baryon spectrum and the baryon couplings are two of the most important issues in hadronic physics andthey are attracting much attention. Both on the experimental and theoretical sides, the nucleon excited states below2.0 GeV have been extensively studied[1]. However, the current information for the properties of states around orabove 2.0 GeV is scarce. On the other hand, in this energy region, many theoretical approaches have predictedmissing N states, which have not been so far observed. Hence, the study of the possible role played by the 2.0GeV region nucleon resonances in the available accurate data is timely and could shed light into the complicateddynamics that governs the high excited nucleon spectrum.
文摘Proton knockout reactions are a widely used tool to study nuclear ground-state distributions. While the interpretation of traditional experiments in direct kinematics has to account for initial and final state interactions, experiments in inverse kinematics can overcome such limitations. We discuss results of an experiment at the BM@N setup at JINR using a <sup>12</sup>C beam at 48 GeV/c to study quasi-elastic scattering reactions, single proton distributions, and short-range correlated nucleon-nucleon pairs. The inverse kinematics allows for the direct measurement of the nucleon-nucleon pair center-of-mass motion and provides first experimental evidence for scale separation of such pairs. Based on these results, we will in the future study neutron-rich nuclei in inverse kinematics in the context of short-range correlations and neutron stars.
基金国家自然科学基金，the Foundation of Harbin Institute of Technology of China
文摘The physical picture of coexistence of both hadronic and QGP phases is given by Friedberg and T.D. Lee's nontopology soliton model. The transport properties of quark in color space and spin space in a system of two-phase coexistence are investigated from both quantum and classical theories.
文摘The hadronic vacuum polarization correction to the photon propagator is found by using the Dubnicka-Meshcheryakov parametrization of the pion form factor and new experimental data on the e^(+)e^(-)→hadrons anniKilation cross section.
基金Supported by the National Natural Science Foundation of China under Grant No 11105060the Fundamental Research Funds for the Central Universities under Grant No HUST 2011QN195.
文摘Elliptic flow v2 is considered as a probe to study partonic collectivity,and the measurement v2/εcan be used to describe the hydro behavior of the colliding system.We study the the effect of the hadronic process on the momentum anisotropy parameter v2 in a multiphase transport model.It is found that hadronic rescattering will depress the v2 signal built up at the partonic phase.A similar mass hierarchy is observed in the model as in the experiment at RHIC.We find that different particle species will approach the same ideal hydro limit if the hadronic process is excluded.
文摘The cross section for three-jet events via the e^(+)e^(−)→hadronic Rindler horizon→qqg process is compared to experimental data from the OPAL collaboration.It is found that the model is consistent with the QCD experiments.
文摘A soft-hard two-component approach to the description of high energy hadronic interactions is proposed.It shows the important role of parton hard scattering in explanation of the chief characteristics of high energy hadronic interactions.
基金National Natural Science Foundation of China(11775275)。
文摘Based on the extended hadronic transport model,we investigate the incompressibility of dense hadronic matter formed in relativistic Au+Au heavy-ion collisions at√SNN=3 GeV.By comparing various experimental observ-ables,such as proton directed ow,production yields of strange hadronsϕ,K−as well as their ratioϕ/K−and proton high-order cumulants with our model calculations,we nd that hadronic interactions play a dominant role in these collisions.
文摘Numerous candidates for exotic hadrons have been detected experimentally in the past two decades,predominantly near the threshold of a pair of hadrons.This study aims to investigate the overall behavior of nearthreshold line shapes in invariant mass distributions.It is noteworthy that the threshold cusp might manifest as a peak only in channels with attractive interaction.The assertion is made that there should be near-threshold structures for any heavy-quark and heavy-antiquark hadron pairs exhibiting attractive interaction at the threshold,as observed in the invariant mass distribution of heavy quarkonium and light hadrons that couple to the open-flavor hadron pair.Furthermore,we have conducted an analysis of potential hadronic molecules comprising pairs of heavy hadrons,utilizing the Bethe-Salpeter equation with constant interactions derived from the one-boson-exchange model.Observed candidates for these hadronic molecules are in good agreement with our predicted spectrum.
基金supported in part by the National Natural Science Foundation of China (Grant Nos.12375073 and 12235018)。
文摘We present a concise review of the vector charmonium state ψ(4230), which was originally labelled as Y(4260)in the literature. As one of the earliest candidates for a quantum chromodynamics exotic states, its interpretation has initiated various ideas about possible manifestations of non-perturbative mechanisms in the charmonium mass regime. In this short article we briefly review the experimental status of ψ(4230) and discuss possible theoretical interpretations. We will focus on four broadly investigated scenarios, i.e., tetraquark, hybrid, hadro-quarkonium,and hadronic molecule, and highlight the key issues based on these approaches. Crucial experimental observables,e.g., mass position, lineshapes, di-lepton decay width Γ_(ee), production rates in B meson decays, dominant hadronic decay patterns, and the potential 1^(-+)and 0^(--)exotic partners, are assessed, which can provide crucial structure information for understanding this mysterious state.
基金supported by the National Natural Science Foundation of China(Grant No.12175318)the Natural Science Foundation of Guangdong Province of China(Grant No.2023A1515011704)。
文摘The observations of fully-charm tetraquark states in the LHCb,CMS,and ATLAS experiments suggested the existence of hadronic molecules of two-charmonium states,which may also imply bound states in the threecharmonium systems.In this work,we study the possible bound states in the triple-ηcand triple-J/ψsystems with J^(PC)=0^(-+)and 1^(--),respectively.In quantum chromodynamics sum rules,we calculate the two-point correlation functions and spectral functions up to the dimension-four gluon condensate.We use the iterative dispersion relation approach to deal with the five-loop banana integrals,which significantly improves computational efficiency.Our results show that the masses of triple-ηcand triple-J/ψstates lie below the corresponding mass thresholds,supporting the existence of such three-body bound states.
基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB34030000)the Guangdong Major Project of Basic and Applied Basic Research(2020B0301030008)the National Natural Science Foundation of China(12025501,11890710,11890714,11775288)。
文摘Spin alignments of vector mesons and hyperons in relativistic heavy-ion collisions have been proposed as signals of global polarization.The STAR experiment first observed the ∧ polarization.Recently,the ALICE collaboration measured the transverse momentum {PT) and the collision centrality dependence of K*,and Φ spin alignments during Pb-Pb collisions at 1/2sNN=2.76 TeV.A large signal is observed in the low pT region of mid-central collisions for K*,while the signal is much smaller for Φ,and these have not been understood yet.Since vector mesons have different lifetimes and their decay products have different scattering cross sections,they suffer from different hadronic effects.In this paper,we study the effect of hadronic interactions on the spin alignment of K*,Φ,and p mesons in relativistic heavy-ion collisions with a multi-phase transport model.We find that hadronic scatterings lead to a deviation of the observed spin alignment matrix element p00 away from the true value for p and K*mesons(with a bigger effect on p) while the effect is negligible for the Φ meson.The effect depends on the kinematic acceptance:the observed p00 value is lower than the true value when the pseudorapidity(η) coverage is small,while there is little effect when the η coverage is large.Hence,this study provides valuable information to understand the vector meson spin alignment signals observed during the experiments.
基金Supported by National Natural Science Foundation of China (10435070,10721140381,10099630)China Ministry of Science and Technology (2007CB16101)Chinese Academy of Sciences (KJCX2-N17,1730911111)
文摘In this paper, we studied the development of hadronic shower in an electromagnetic calorimeter of Alpha Magnetic Spectrometer Ⅱ. Two parametrized empirical formulae were proposed to describe the hadronic shower shape in calorimeter. Using 100 GeV proton beam incident on the center of the ECAL, detailed plots of lateral and longitudinal hadronic shower behavior were given and we found the formulae can describe the development of the hadronic shower with the test beam data. The possible application of the parametrized formulae including e±-π± discrimination and tau jet reconstruction was discussed.
基金Supported by National Natural Science Foundation of China(11175111)
文摘In high-temperature quark-gluon plasma and its subsequent hadronic matter created in a high-energy nucleus-nucleus collision, the quark-antiquark potential depends on the temperature. The temperature-dependent potential is expected to be derived from the free energy obtained in lattice gauge theory calculations. This requires one to study the relationship between the quark-antiquark potential and the quark-antiquark free energy. When the system＇s temperature is above the critical temperature, the potential of a heavy quark and a heavy antiquark almost equals the free energy, but the potential of a light quark and a light antiquark, of a heavy quark and a light antiquark and of a light quark and a heavy antiquark is substantially larger than the free energy. When the system＇s temperature is below the critical temperature, the quark-antiquark free energy can be taken as the quark-antiquark potential. This allows one to apply the quark-antiquark free energy to study hadron properties and hadron-hadron reactions in hadronic matter.
