It is an ideal place to search for exotic states through J/ψ hadronic decays.In this paper,we discuss the way to use the partial wave analysis (PWA) based on covariant helicity amplitude analysis to study the invaria...It is an ideal place to search for exotic states through J/ψ hadronic decays.In this paper,we discuss the way to use the partial wave analysis (PWA) based on covariant helicity amplitude analysis to study the invariant mass spectrum of ηπ and to find the evidence of the existence of exotic states in this channel.The formula for PWA is also given.It is the theoretical foundation of experimental physics analysis on exotic states searching in J/ψ hadronic decays.The theoretical formula can also be used in physics analysis of J/ψ decays into ωππ，φππ，ωKK，φKK and K^* (892)Kπ.展开更多
By employing the perturbative QCD （pQCD） factorization approach, we calculate some important next- to-leading-order （NLO） contributions to the two-body charmless hadronic decays B^＋ →ρ^＋η（＇） and B^0 → ρ^...By employing the perturbative QCD （pQCD） factorization approach, we calculate some important next- to-leading-order （NLO） contributions to the two-body charmless hadronic decays B^＋ →ρ^＋η（＇） and B^0 → ρ^0（ω, φ）η（＇）, induced by the vertex QCD corrections, the quark-loops as well as the chromo-magnetic penguins. From the numerical results and phenomenological analysis we find that （a） for B^± → ρ^±η（＇） （B^0 → ρ^0（ω, φ）η（＇）decays, the partial NLO contributions to branching ratios are small （large） in magnitude; and （b） the pQCD predictions for ACP^dir（B^± → ρ^±η（＇）） are consistent with the data, while the predicted .ACP（B^0 → ρ^0（ω）η（＇）） are generally large in magnitude and could be tested by the forthcoming LHCb experiments.展开更多
Based on shell model of nuclei, the influence of a high magnetic field on β^＋ decay in the crusts of accreting neutron stars is analyzed. The magnetic field effect on 54 Mn is discussed. The results show that a weak...Based on shell model of nuclei, the influence of a high magnetic field on β^＋ decay in the crusts of accreting neutron stars is analyzed. The magnetic field effect on 54 Mn is discussed. The results show that a weak magnetic field makes little effect on β^＋ decay but a strong magnetic field （B 〉 10^11 G） improves β^＋ decay rates obviously. The conclusion derived will benefit to develop further research on nuclear astrophysics in the future.展开更多
Along with the running of Large Hadron Collider(LHC)located at CERN in November 2009,a large number of data samples of Bc meson have been collected and some hadronic Bc decay modes have been measured by the LHC experi...Along with the running of Large Hadron Collider(LHC)located at CERN in November 2009,a large number of data samples of Bc meson have been collected and some hadronic Bc decay modes have been measured by the LHC experiments.In view of the special and important roles of Bc meson decays playing in the heavy flavor sector,we here give a short review on the status of two body hadronic decays Bc!M1M2at both experimental and theoretical aspects.For the theoretical progresses,specifically,we will show lots of theoretical studies on two body hadronic Bcdecays involving pseudoscalar,vector,scalar,axial-vector,even tensor meson(s)in the final states by employing the perturbative QCD(pQCD)factorization approach.We will present a general analysis about the twobody hadronic decays of the heavy Bc meson and also provide some expectations for the future developments.展开更多
In the framework of the NRQCD factorization formalism,we calculate the decay rate for the process Υ(1 S) → ccgg to the next-to-leading order(NLO) in the relative velocity v of the b quark in the bottomonium rest fra...In the framework of the NRQCD factorization formalism,we calculate the decay rate for the process Υ(1 S) → ccgg to the next-to-leading order(NLO) in the relative velocity v of the b quark in the bottomonium rest frame.We also study the momentum distributions of the charm quark and the charmed-hadron in the decay.The momentum distribution of the charmed-hadron is obtained by convolving the charm quark momentum distribution with a fragmentation function of the charm quark into the hadron.In addition,we fit the nonperturbative NRQCD matrix element v 2 Υ through comparing the theoretical prediction with the measurement from the BaBar collaboration for the decay rate of Υ(1 S) → D + X.In return,taking this matrix element as an input parameter,we predict the decay rates as well as the momentum distributions for a collection of charmed-hadrons in the process Υ(1S) → ccgg → hX.展开更多
In this article, we assign the higher charm mesons D1^＊（2680）, D3^＊（2760）, D2^＊（3000） to be the 2S 1^-, 1D3^- and 1F 2^＋ states, respectively, and study the two-body strong decays to the ground state charm m...In this article, we assign the higher charm mesons D1^＊（2680）, D3^＊（2760）, D2^＊（3000） to be the 2S 1^-, 1D3^- and 1F 2^＋ states, respectively, and study the two-body strong decays to the ground state charm mesons and light pseudoscalar mesons with the heavy meson effective theory. We obtain the ratios among the strong decays, which can be confronted to the experimental data in the future and shed light on the nature of those higher charm mesons.展开更多
We study strong decays of the possible fully-charm tetraquarks recently observed by LHCb,and calculate their relative branching ratios through the Fierz rearrangement.Together with our previous QCD sum rule study,our ...We study strong decays of the possible fully-charm tetraquarks recently observed by LHCb,and calculate their relative branching ratios through the Fierz rearrangement.Together with our previous QCD sum rule study,our results suggest that the broad structure around 6.2–6.8 GeV can be interpreted as an S-wave cccc tetraquark state with JPC=0++or 2++,and the narrow structure around 6.9 GeV can be interpreted as a P-wave one with JPC=0-+or 1-+.These structures were observed in the di-J=w invariant mass spectrum,and we propose to confirm them in the di-gc;J/ψhc;ηcχc0,and ηcχc1channels.We also propose to search for their partner states having the negative charge-conjugation parity in the J/ψηc;J/ψχc0;J/ψχc1,and ηchc channels.展开更多
基金Supported by the National Natural Science Foundation of China(10935007,11305180)the National Program on Key Basic Research Project of China(973 Program)(2009CB825200,2015CB856700)
文摘It is an ideal place to search for exotic states through J/ψ hadronic decays.In this paper,we discuss the way to use the partial wave analysis (PWA) based on covariant helicity amplitude analysis to study the invariant mass spectrum of ηπ and to find the evidence of the existence of exotic states in this channel.The formula for PWA is also given.It is the theoretical foundation of experimental physics analysis on exotic states searching in J/ψ hadronic decays.The theoretical formula can also be used in physics analysis of J/ψ decays into ωππ，φππ，ωKK，φKK and K^* (892)Kπ.
基金Supported by the National Natural Science Foundation of China under Grant No.10575052,10605012,and 10735080
文摘By employing the perturbative QCD （pQCD） factorization approach, we calculate some important next- to-leading-order （NLO） contributions to the two-body charmless hadronic decays B^＋ →ρ^＋η（＇） and B^0 → ρ^0（ω, φ）η（＇）, induced by the vertex QCD corrections, the quark-loops as well as the chromo-magnetic penguins. From the numerical results and phenomenological analysis we find that （a） for B^± → ρ^±η（＇） （B^0 → ρ^0（ω, φ）η（＇）decays, the partial NLO contributions to branching ratios are small （large） in magnitude; and （b） the pQCD predictions for ACP^dir（B^± → ρ^±η（＇）） are consistent with the data, while the predicted .ACP（B^0 → ρ^0（ω）η（＇）） are generally large in magnitude and could be tested by the forthcoming LHCb experiments.
基金The project supported by National Natural Science Foundation of China under Grant No. 10347008
文摘Based on shell model of nuclei, the influence of a high magnetic field on β^＋ decay in the crusts of accreting neutron stars is analyzed. The magnetic field effect on 54 Mn is discussed. The results show that a weak magnetic field makes little effect on β^＋ decay but a strong magnetic field （B 〉 10^11 G） improves β^＋ decay rates obviously. The conclusion derived will benefit to develop further research on nuclear astrophysics in the future.
基金supported by the National Natural Science Foundation of China (11205072,10975074 and 11235005)
文摘Along with the running of Large Hadron Collider(LHC)located at CERN in November 2009,a large number of data samples of Bc meson have been collected and some hadronic Bc decay modes have been measured by the LHC experiments.In view of the special and important roles of Bc meson decays playing in the heavy flavor sector,we here give a short review on the status of two body hadronic decays Bc!M1M2at both experimental and theoretical aspects.For the theoretical progresses,specifically,we will show lots of theoretical studies on two body hadronic Bcdecays involving pseudoscalar,vector,scalar,axial-vector,even tensor meson(s)in the final states by employing the perturbative QCD(pQCD)factorization approach.We will present a general analysis about the twobody hadronic decays of the heavy Bc meson and also provide some expectations for the future developments.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10875130,10935012,and 10875156
文摘In the framework of the NRQCD factorization formalism,we calculate the decay rate for the process Υ(1 S) → ccgg to the next-to-leading order(NLO) in the relative velocity v of the b quark in the bottomonium rest frame.We also study the momentum distributions of the charm quark and the charmed-hadron in the decay.The momentum distribution of the charmed-hadron is obtained by convolving the charm quark momentum distribution with a fragmentation function of the charm quark into the hadron.In addition,we fit the nonperturbative NRQCD matrix element v 2 Υ through comparing the theoretical prediction with the measurement from the BaBar collaboration for the decay rate of Υ(1 S) → D + X.In return,taking this matrix element as an input parameter,we predict the decay rates as well as the momentum distributions for a collection of charmed-hadrons in the process Υ(1S) → ccgg → hX.
基金Supported by National Natural Science Foundation of China under Grant No.11375063Natural Science Foundation of Hebei Province under Grant No.A2014502017
文摘In this article, we assign the higher charm mesons D1^＊（2680）, D3^＊（2760）, D2^＊（3000） to be the 2S 1^-, 1D3^- and 1F 2^＋ states, respectively, and study the two-body strong decays to the ground state charm mesons and light pseudoscalar mesons with the heavy meson effective theory. We obtain the ratios among the strong decays, which can be confronted to the experimental data in the future and shed light on the nature of those higher charm mesons.
基金supported by the National Natural Science Foundation of China (11722540 and 11975033)the Chinese National Youth Thousand Talents Program+2 种基金the China National Funds for Distinguished Young Scientists (11825503)the National Program for Support of Top-notch Young Professionalsthe Fundamental Research Funds for the Central Universities。
文摘We study strong decays of the possible fully-charm tetraquarks recently observed by LHCb,and calculate their relative branching ratios through the Fierz rearrangement.Together with our previous QCD sum rule study,our results suggest that the broad structure around 6.2–6.8 GeV can be interpreted as an S-wave cccc tetraquark state with JPC=0++or 2++,and the narrow structure around 6.9 GeV can be interpreted as a P-wave one with JPC=0-+or 1-+.These structures were observed in the di-J=w invariant mass spectrum,and we propose to confirm them in the di-gc;J/ψhc;ηcχc0,and ηcχc1channels.We also propose to search for their partner states having the negative charge-conjugation parity in the J/ψηc;J/ψχc0;J/ψχc1,and ηchc channels.
