QCD theory predicts the existence of glueballs,but so far all experimental endeavors have failed to identify any such states.To remedy this discrepancy between QCD,which has proven to be a successful theory for strong...QCD theory predicts the existence of glueballs,but so far all experimental endeavors have failed to identify any such states.To remedy this discrepancy between QCD,which has proven to be a successful theory for strong interactions,and the failure of experimental searches for glueballs,one is tempted to accept the promising interpretation that the glueballs mix with regular qq states of the same quantum numbers.The lattice estimate of the masses of pure 0++ glueballs ranges from 1 to 2 GeV,which is the region of the f_(0)family.Thus many authors suggest that the f_(0) mesonic series is an ideal place to study possible mixtures of glueballs and qq.In this paper,following the strategy proposed by Close,Farrar and Li,we try to determine the fraction of glueball components inf_(0)mesons using the measured mass spectra and the branching ratios of J/ψ radiative decays intof_(0)mesons.Since the pioneering papers by Close et al.,more than 20 years have elapsed and more accurate measurements have been done by several experimental collaborations,so it is time to revisit this interesting topic using new data.We suppose f_(0)(500)and f_(0)(980)to be pure quark states,while for f_(0)(1370),f_(0)(1500)and f_(0)(1710),to fit both the experimental data of J/ψradiative decay and their mass spectra,glueball components are needed.Moreover,the mass of the pure 0++ glueball is phenomenologically determined.展开更多
We study the ■_(s)^(0)→J/ψf_(0)(980) and ■_(s)^(0)→J/ψa_(0)(980) reactions,and pay attention to the different sources of iso spin violation and mixing of f_(0)(980) and a_(0)(980) resonances where these resonanc...We study the ■_(s)^(0)→J/ψf_(0)(980) and ■_(s)^(0)→J/ψa_(0)(980) reactions,and pay attention to the different sources of iso spin violation and mixing of f_(0)(980) and a_(0)(980) resonances where these resonances are dynamically generated from meson-meson interactions.We find that the main cause of isospin violation is isospin breaking in the meson-meson transition T matrices,and the other source is that the loops involving kaons in the production mechanism do not cancel due to the different masses of charged and neutral kaons.We obtain a branching ratio for a_(0)(980)production of the order of 5×10^(-6).Future experiments can address this problem,and the production rate and shape of the π^(0)η mass distribution will definitely help to better understand the nature of scalar resonances.展开更多
基金Supported by National Natural Science Foundation of China(11805160,11747040,11675082,11605039)。
文摘QCD theory predicts the existence of glueballs,but so far all experimental endeavors have failed to identify any such states.To remedy this discrepancy between QCD,which has proven to be a successful theory for strong interactions,and the failure of experimental searches for glueballs,one is tempted to accept the promising interpretation that the glueballs mix with regular qq states of the same quantum numbers.The lattice estimate of the masses of pure 0++ glueballs ranges from 1 to 2 GeV,which is the region of the f_(0)family.Thus many authors suggest that the f_(0) mesonic series is an ideal place to study possible mixtures of glueballs and qq.In this paper,following the strategy proposed by Close,Farrar and Li,we try to determine the fraction of glueball components inf_(0)mesons using the measured mass spectra and the branching ratios of J/ψ radiative decays intof_(0)mesons.Since the pioneering papers by Close et al.,more than 20 years have elapsed and more accurate measurements have been done by several experimental collaborations,so it is time to revisit this interesting topic using new data.We suppose f_(0)(500)and f_(0)(980)to be pure quark states,while for f_(0)(1370),f_(0)(1500)and f_(0)(1710),to fit both the experimental data of J/ψradiative decay and their mass spectra,glueball components are needed.Moreover,the mass of the pure 0++ glueball is phenomenologically determined.
基金partly supported by the National Natural Science Foundation of China (11975083,12147211)partly supported by the Spanish Ministerio de Economia y Competitividad and European FEDER funds (FIS2017-84038-C2-1-P B)+1 种基金Generalitat Valenciana (PROMETEO/2020/023)funding from the European Unions Horizon 2020 research and innovation programme (824093) for the"STRONG-2020"project。
文摘We study the ■_(s)^(0)→J/ψf_(0)(980) and ■_(s)^(0)→J/ψa_(0)(980) reactions,and pay attention to the different sources of iso spin violation and mixing of f_(0)(980) and a_(0)(980) resonances where these resonances are dynamically generated from meson-meson interactions.We find that the main cause of isospin violation is isospin breaking in the meson-meson transition T matrices,and the other source is that the loops involving kaons in the production mechanism do not cancel due to the different masses of charged and neutral kaons.We obtain a branching ratio for a_(0)(980)production of the order of 5×10^(-6).Future experiments can address this problem,and the production rate and shape of the π^(0)η mass distribution will definitely help to better understand the nature of scalar resonances.
