Within the framework of nonrelativistic quantum chronodynamics factorization,we investigate relativistic corrections to the production of a pair of Bc family mesons in e^(+)e^(-)annihilation.The study covers center-of...Within the framework of nonrelativistic quantum chronodynamics factorization,we investigate relativistic corrections to the production of a pair of Bc family mesons in e^(+)e^(-)annihilation.The study covers center-ofmass energies from the production threshold up to 2 m_(z),considering both the photon and Z^(0)-boson propagated processes.We find that the relativistic corrections are significant,with the corresponding K factors of approximately 0.6.The azimuthal asymmetry,angular distribution,and transverse momentum distribution are also presented.展开更多
We study the Bc meson rare decay in order to search for the Majorana neutrino signal. It is found that the corresponding decay rate is sensitive to the Majorana neutrino mass and mixing angles. The signal of B~ --~ li...We study the Bc meson rare decay in order to search for the Majorana neutrino signal. It is found that the corresponding decay rate is sensitive to the Majorana neutrino mass and mixing angles. The signal of B~ --~ lil l~ Mm induced by the Majorana neutrino within the mass region mr 〈 mn 〈mB may be observed at LHCb.展开更多
In this study,we investigate the production of doubly charmed baryons from anti-bottom charmedmesons.Using the effective Lagrangian approach,we discuss triangle diagrams at the hadronic level to access thebranching ra...In this study,we investigate the production of doubly charmed baryons from anti-bottom charmedmesons.Using the effective Lagrangian approach,we discuss triangle diagrams at the hadronic level to access thebranching ratios of B_(c)→B(ccq)+B(c^(-)q^(-)q^(-)).Apparently,the specific process B_(c)→Ξ_(cc)^(+)Ξ′_(c^(-))^(0) occupies the largest possibilityon the order of 9.1×10^(-5).In addition,although the production of undiscovered Ω_(cc)^(+) is Cabibbo suppressed in B^(-)_(c)→Ω_(cc)^(+)Ξ_(c^(-))^(0),its branching ratio can still reach a level of 10^(-7).These results are expected to provide valuable supportfor future experiments.展开更多
The semileptonic decays B+c → P(V) + l+ + vt and the nonleptonic decays B+c → P(V) + L, where P(V) denotes a pseudoscalar (vector) charmonium or (bs)-meson, and L denotes a light meson, are studied i...The semileptonic decays B+c → P(V) + l+ + vt and the nonleptonic decays B+c → P(V) + L, where P(V) denotes a pseudoscalar (vector) charmonium or (bs)-meson, and L denotes a light meson, are studied in the framework of improved instantaneous Bethe- Salpeter (BS) equation and the Mandelstam formula. The numerical results (width and branching ratio of the decays) are presented in tables, and in order to compare conveniently, those obtained by other approaches are also put in the relevant tables. Based on the fact that the ratio BR(B+c→ψ(2S)π+)/BR(B+c→J/ψπ+)=0.24^+0.023_-0.040 estimated here is in good agreement with the observation by LHCb BR(B+c→ψ(2S)π+)/BR(B+c→J/ψπ+)=0.250 ± 0.068(stat) ± 0.014(syst) ± 0.006(B), one may conclude that with respect to the decays the present framework works quite well.展开更多
The production of Bc and B* mesons at a Z-factory (an e+e- collider operating at energies around the Z pole) is calculated up to the next-to-leading order (NLO) QCD accuracy. The results show that the dependence...The production of Bc and B* mesons at a Z-factory (an e+e- collider operating at energies around the Z pole) is calculated up to the next-to-leading order (NLO) QCD accuracy. The results show that the dependence of the total cross sections on the renormalization scale/1 is suppressed by the corrections, and the NLO corrections enhance the total cross sections of B,. by 52% and of Bc* by 33% when the renormalization scale is taken at μ = 2mb. To observe the various behaviors of the production of the mesons Bc and Bc*, such as the differential cross section vs. the out-going angle, the forward-backward asymmetry, and the distribution vs. the energy fraction z up to NLO QCD accuracy as well as the relevant K-factor (NLO to LO) for the production, are calculated, and it is pointed out that some of the observables obtained in the present work may be used as a specific precision test of the standard model.展开更多
We analyze different decay observables of semileptonic decays Bc→(Ds,d(*))μ+μ-,such as the branching ratio,forward-backward asymmetry,polarization fraction,and lepton polarization asymmetry in the non-universal Z’...We analyze different decay observables of semileptonic decays Bc→(Ds,d(*))μ+μ-,such as the branching ratio,forward-backward asymmetry,polarization fraction,and lepton polarization asymmetry in the non-universal Z’model.We further study the dependence of the branching fraction to the new model parameters and find that the values of different decay parameters increase in the Z’model,which indicates a possible approach for the search of new physics as well as for the unknown phenomena of the charm B meson.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
The Bc → Bsπ decay is studied with the perturbative QCD approach. Three types of wave functions for Bs meson are considered. The transition form factor F0Bc → Bsπ (0) and the branching ratio IBr(Bc → Bsπ) ar...The Bc → Bsπ decay is studied with the perturbative QCD approach. Three types of wave functions for Bs meson are considered. The transition form factor F0Bc → Bsπ (0) and the branching ratio IBr(Bc → Bsπ) are sensitive to the model of the Bs meson wave functions. With appropriate inputs, our estimate on 23r(Bc → Bsπ) is comparable with the recent LHCb measurement. A clear signal of Bc → Bsπ decay should be easily observed at the Large Hadron Collider.展开更多
The ground vector Bc*meson has not yet been experimentally discovered until now.Besides the dominant electromagnetic decays,nonleptonic weak decays provide another choice to search for the mysterious Bc*mesons.Inspire...The ground vector Bc*meson has not yet been experimentally discovered until now.Besides the dominant electromagnetic decays,nonleptonic weak decays provide another choice to search for the mysterious Bc*mesons.Inspired by the potential prospects of Bc*mesons in future high-luminosity colliders,nonleptonic Bc*weak decays induced by bottom and charm quark decays are studied within the SM by using a naive factorization approach.It is found that for Bc*→Bs,dπ,Bs,d*π,Bs,dρ,BsK,Bs*K,BsK*,ηc(1S,2S)π,ηc(1S,2S)ρandψ(1S,2S)πdecays,a few hundred and even thousands of events might be observable in CEPC,FCC-ee and LHCb@HL-LHC experiments.展开更多
基金Supported by the National Natural Science Foundation of China(11705078,12575087)。
文摘Within the framework of nonrelativistic quantum chronodynamics factorization,we investigate relativistic corrections to the production of a pair of Bc family mesons in e^(+)e^(-)annihilation.The study covers center-ofmass energies from the production threshold up to 2 m_(z),considering both the photon and Z^(0)-boson propagated processes.We find that the relativistic corrections are significant,with the corresponding K factors of approximately 0.6.The azimuthal asymmetry,angular distribution,and transverse momentum distribution are also presented.
基金Supported by the National Science Foundation of China under Grant No.11275114China Postdoctoral Science Foundation under Grant No.2012T50604Natural Science Foundation of Shandong Province under Grant No.ZR2011AQ013
文摘We study the Bc meson rare decay in order to search for the Majorana neutrino signal. It is found that the corresponding decay rate is sensitive to the Majorana neutrino mass and mixing angles. The signal of B~ --~ lil l~ Mm induced by the Majorana neutrino within the mass region mr 〈 mn 〈mB may be observed at LHCb.
基金support by National Natural Science Foundation of China(12005294)the Fundamental Funds for Key disciplines in Physics(2022WLXK05)supported by National Natural Science Foundation of China(12105247)。
文摘In this study,we investigate the production of doubly charmed baryons from anti-bottom charmedmesons.Using the effective Lagrangian approach,we discuss triangle diagrams at the hadronic level to access thebranching ratios of B_(c)→B(ccq)+B(c^(-)q^(-)q^(-)).Apparently,the specific process B_(c)→Ξ_(cc)^(+)Ξ′_(c^(-))^(0) occupies the largest possibilityon the order of 9.1×10^(-5).In addition,although the production of undiscovered Ω_(cc)^(+) is Cabibbo suppressed in B^(-)_(c)→Ω_(cc)^(+)Ξ_(c^(-))^(0),its branching ratio can still reach a level of 10^(-7).These results are expected to provide valuable supportfor future experiments.
基金supported by the National Natural Science Foundation of China(Grant Nos.11175051,11275243 and 11147001)the Fundamental Research Funds for the Central Universities and partially Program for Innovation Research of Science in Harbin Institute of Technology
文摘The semileptonic decays B+c → P(V) + l+ + vt and the nonleptonic decays B+c → P(V) + L, where P(V) denotes a pseudoscalar (vector) charmonium or (bs)-meson, and L denotes a light meson, are studied in the framework of improved instantaneous Bethe- Salpeter (BS) equation and the Mandelstam formula. The numerical results (width and branching ratio of the decays) are presented in tables, and in order to compare conveniently, those obtained by other approaches are also put in the relevant tables. Based on the fact that the ratio BR(B+c→ψ(2S)π+)/BR(B+c→J/ψπ+)=0.24^+0.023_-0.040 estimated here is in good agreement with the observation by LHCb BR(B+c→ψ(2S)π+)/BR(B+c→J/ψπ+)=0.250 ± 0.068(stat) ± 0.014(syst) ± 0.006(B), one may conclude that with respect to the decays the present framework works quite well.
基金supported by the National Natural Science Foundation of China(Grant Nos.11275243,11275036,11447601,11535002,and 11675239)
文摘The production of Bc and B* mesons at a Z-factory (an e+e- collider operating at energies around the Z pole) is calculated up to the next-to-leading order (NLO) QCD accuracy. The results show that the dependence of the total cross sections on the renormalization scale/1 is suppressed by the corrections, and the NLO corrections enhance the total cross sections of B,. by 52% and of Bc* by 33% when the renormalization scale is taken at μ = 2mb. To observe the various behaviors of the production of the mesons Bc and Bc*, such as the differential cross section vs. the out-going angle, the forward-backward asymmetry, and the distribution vs. the energy fraction z up to NLO QCD accuracy as well as the relevant K-factor (NLO to LO) for the production, are calculated, and it is pointed out that some of the observables obtained in the present work may be used as a specific precision test of the standard model.
基金DST,Govt.of India for the INSPIRE Fellowship(IF160115)SERB,DST,Govt.of India for financial support through project(EMR/2015/000817)。
文摘We analyze different decay observables of semileptonic decays Bc→(Ds,d(*))μ+μ-,such as the branching ratio,forward-backward asymmetry,polarization fraction,and lepton polarization asymmetry in the non-universal Z’model.We further study the dependence of the branching fraction to the new model parameters and find that the values of different decay parameters increase in the Z’model,which indicates a possible approach for the search of new physics as well as for the unknown phenomena of the charm B meson.
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(Grant Nos.11147008,U1232101 and 11275057)
文摘The Bc → Bsπ decay is studied with the perturbative QCD approach. Three types of wave functions for Bs meson are considered. The transition form factor F0Bc → Bsπ (0) and the branching ratio IBr(Bc → Bsπ) are sensitive to the model of the Bs meson wave functions. With appropriate inputs, our estimate on 23r(Bc → Bsπ) is comparable with the recent LHCb measurement. A clear signal of Bc → Bsπ decay should be easily observed at the Large Hadron Collider.
基金Supported by the National Natural Science Foundation of China(11705047,12275068,U1632109,11875122)the Natural Science Foundation of Henan Province,China(222300420479)the Excellent Youth Foundation of Henan Province,China(212300410010)。
文摘The ground vector Bc*meson has not yet been experimentally discovered until now.Besides the dominant electromagnetic decays,nonleptonic weak decays provide another choice to search for the mysterious Bc*mesons.Inspired by the potential prospects of Bc*mesons in future high-luminosity colliders,nonleptonic Bc*weak decays induced by bottom and charm quark decays are studied within the SM by using a naive factorization approach.It is found that for Bc*→Bs,dπ,Bs,d*π,Bs,dρ,BsK,Bs*K,BsK*,ηc(1S,2S)π,ηc(1S,2S)ρandψ(1S,2S)πdecays,a few hundred and even thousands of events might be observable in CEPC,FCC-ee and LHCb@HL-LHC experiments.