We present here a two-step method of classification and calculation for decay rates in the Standard Model. The first step is a phenomenological classification method, which is an extended and improved schematic experi...We present here a two-step method of classification and calculation for decay rates in the Standard Model. The first step is a phenomenological classification method, which is an extended and improved schematic experimental formula for decay width originally introduced by Chang. This schematic formula separates decays into seven classes. Furthermore, from it is derived a process-specific interaction energy m<sub>X</sub>. The second step is a numerical calculation method, which calculates this interaction energy m<sub>X</sub> numerically by minimization of action from the Lagrangian of the process, from which follows the decay width via the phenomenological formula. The Lagrangian is based on an extension of the Standard Model, the extended SU(4)-preon-model. A comparison of numerically calculated and observed decay widths for a large selection of decays shows a good agreement.展开更多
Within the hidden local symmetry framework, the Dalitz decay η→Ve＋e-is studied with the vector meson dominance model. It is found that the partial width Γ（η→ωe＋e-）≈40 e V and branching ratio B（η→ωe＋e-...Within the hidden local symmetry framework, the Dalitz decay η→Ve＋e-is studied with the vector meson dominance model. It is found that the partial width Γ（η→ωe＋e-）≈40 e V and branching ratio B（η→ωe＋e-）≈2×10^-4, and Γ（η→ρe＋e-）≈10Γ（η→ωe＋e-） and B（η→ρe＋e-）≈10B（η→ωe＋e-）. The maximum position of the dilepton distribution is m e＋e-≈1.33 Me V. These decays are measurable with the advent of high statistic ηexperiments.展开更多
We present the semileptonic decay of Bc meson in a QCD potential model with the coulombic part of the Cornell potential -4αs/3r+br+c as perturbation. Computing the slope and curvature of Isgur Wise function in this a...We present the semileptonic decay of Bc meson in a QCD potential model with the coulombic part of the Cornell potential -4αs/3r+br+c as perturbation. Computing the slope and curvature of Isgur Wise function in this approach, we study the pseudoscalar and vector form factors for the transition of Bc meson to its S wave charmonium states. Numerical estimates of widths for the transitions of Bc→J|ψ(ηc)lv1 are presented.展开更多
Mixing between the 2^3S1 and 1^3D1Ds is studied within the 3P0 model. If mixing between these two 1 states exists, Ds1^＊ （2700） ± and DsJ^＊（2860）± could be interpreted as the two orthogonal mixed state...Mixing between the 2^3S1 and 1^3D1Ds is studied within the 3P0 model. If mixing between these two 1 states exists, Ds1^＊ （2700） ± and DsJ^＊（2860）± could be interpreted as the two orthogonal mixed states with mixing angle θ ≈-80 °in the case of a special β for each meson. However, in the case of a universal β for all mesons, D_（s1）~＊（2700） ± could be interpreted as the mixed state of 23S1 and 13D1 with mixing angle 12° θ 21° but D_（sJ）~＊（2860）± seems difficult to interpret as the orthogonal partner of D（s1）~＊（2700）±.展开更多
In this work, we tentatively assign the charmed mesons D J（2580）, D＊J（2650）, D J（2740）, D＊J（2760）,D J（3000） and D＊J（3000） observed by the LHCb collaboration according to their spin, parity and masses, t...In this work, we tentatively assign the charmed mesons D J（2580）, D＊J（2650）, D J（2740）, D＊J（2760）,D J（3000） and D＊J（3000） observed by the LHCb collaboration according to their spin, parity and masses, then systematically study their strong decays to ground state charmed mesons plus pseudoscalar mesons with the3P0 decay model. Based on these studies, we assign the D＊J（2760） as the 1D5/23-state, the D＊J（3000） as the 1F5/22＋or 1F7/24＋state, the D J（3000） as the 1F7/23＋or 2P1/21＋state in the D meson family. As a byproduct, we also study the strong decays of the states 2P1/20＋, 2P3/22＋, 3S1/21-, 3S1/20-etc, which will be valuable in searching for the partners of these D mesons.展开更多
文摘We present here a two-step method of classification and calculation for decay rates in the Standard Model. The first step is a phenomenological classification method, which is an extended and improved schematic experimental formula for decay width originally introduced by Chang. This schematic formula separates decays into seven classes. Furthermore, from it is derived a process-specific interaction energy m<sub>X</sub>. The second step is a numerical calculation method, which calculates this interaction energy m<sub>X</sub> numerically by minimization of action from the Lagrangian of the process, from which follows the decay width via the phenomenological formula. The Lagrangian is based on an extension of the Standard Model, the extended SU(4)-preon-model. A comparison of numerically calculated and observed decay widths for a large selection of decays shows a good agreement.
基金Supported by National Natural Science Foundation of China(11147008,11275057,U1332103,U1232101)Program for Science and Technology Innovation Talents in Universities of Henan Province(2012HASTIT030)
文摘Within the hidden local symmetry framework, the Dalitz decay η→Ve＋e-is studied with the vector meson dominance model. It is found that the partial width Γ（η→ωe＋e-）≈40 e V and branching ratio B（η→ωe＋e-）≈2×10^-4, and Γ（η→ρe＋e-）≈10Γ（η→ωe＋e-） and B（η→ρe＋e-）≈10B（η→ωe＋e-）. The maximum position of the dilepton distribution is m e＋e-≈1.33 Me V. These decays are measurable with the advent of high statistic ηexperiments.
文摘We present the semileptonic decay of Bc meson in a QCD potential model with the coulombic part of the Cornell potential -4αs/3r+br+c as perturbation. Computing the slope and curvature of Isgur Wise function in this approach, we study the pseudoscalar and vector form factors for the transition of Bc meson to its S wave charmonium states. Numerical estimates of widths for the transitions of Bc→J|ψ(ηc)lv1 are presented.
基金Supported by National Natural Science Foundation of China(11075102)
文摘Mixing between the 2^3S1 and 1^3D1Ds is studied within the 3P0 model. If mixing between these two 1 states exists, Ds1^＊ （2700） ± and DsJ^＊（2860）± could be interpreted as the two orthogonal mixed states with mixing angle θ ≈-80 °in the case of a special β for each meson. However, in the case of a universal β for all mesons, D_（s1）~＊（2700） ± could be interpreted as the mixed state of 23S1 and 13D1 with mixing angle 12° θ 21° but D_（sJ）~＊（2860）± seems difficult to interpret as the orthogonal partner of D（s1）~＊（2700）±.
基金Supported by National Natural Science Foundation of China(11375063)Fundamental Research Funds for the Central Universities(13QN59,2014MS165)
文摘In this work, we tentatively assign the charmed mesons D J（2580）, D＊J（2650）, D J（2740）, D＊J（2760）,D J（3000） and D＊J（3000） observed by the LHCb collaboration according to their spin, parity and masses, then systematically study their strong decays to ground state charmed mesons plus pseudoscalar mesons with the3P0 decay model. Based on these studies, we assign the D＊J（2760） as the 1D5/23-state, the D＊J（3000） as the 1F5/22＋or 1F7/24＋state, the D J（3000） as the 1F7/23＋or 2P1/21＋state in the D meson family. As a byproduct, we also study the strong decays of the states 2P1/20＋, 2P3/22＋, 3S1/21-, 3S1/20-etc, which will be valuable in searching for the partners of these D mesons.
