Exclusive decays J/ψ(ψ') → Y(Y-) (Y = A,∑0, -) are studied in the quark model by combining thestructure of hyperons in the transition. The branching ratios are evaluated contrastively by adopting different hyp...Exclusive decays J/ψ(ψ') → Y(Y-) (Y = A,∑0, -) are studied in the quark model by combining thestructure of hyperons in the transition. The branching ratios are evaluated contrastively by adopting different hyperonwavefunctions, SU(6) basis, and uds basis, which account for SU(3)f breaking, and the results show that the differentdescription of quark mass breaking plays an important role in the evaluation of the decay width for processes J/ψ(ψ') →Y(Y-).展开更多
We develop a method for calculation of the total reaction cross sections induced by the halo nuclei and stable nuclei. This approach is based on the Glauber theory, which is valid for nuclear reactions at high energie...We develop a method for calculation of the total reaction cross sections induced by the halo nuclei and stable nuclei. This approach is based on the Glauber theory, which is valid for nuclear reactions at high energies. It is extended for nuclear reactions at low energies and intermediate energies by including both the quantum correction and Coulomb correction under the assumption of the effective nuclear density distribution. The calculated results of the total reaction cross section induced by stable nuclei agree well with 30 experimental data within 10 percent accuracy.The comparison between the numerical results and 20 experimental data for the total nuclear reaction cross section induced by the neutron halo nuclei and the proton halo nuclei indicates a satisfactory agreement after considering the halo structure of these nuclei, which implies quite digerent mean fields for the nuclear reactions induced by halo nuclei and stable nuclei. The halo nucleon distributions and the root-mean-square radii of these nuclei can be extracted from the above comparison based on the improved Glauber model, which indicates clearly the halo structures of these nuclei. Especially,it is clear to see that the medium correction of the nucleon-nucleon collision has little effect on the total reaction cross sections, induced by the halo nuclei due to the very weak binding and the very extended density distribution.展开更多
A quark pair creation model is introduced to study the XeJ exclusive decays into baryon-antibarvon pairs.The decay widths for processes Xcj→B(B^-) (J=0, 2;B=∧,∑^0,Ξ^-) are evaluated phenomenologically with an expl...A quark pair creation model is introduced to study the XeJ exclusive decays into baryon-antibarvon pairs.The decay widths for processes Xcj→B(B^-) (J=0, 2;B=∧,∑^0,Ξ^-) are evaluated phenomenologically with an explicit inclusion of the properties for outgoing baryons described by wave functions in the naive quark model. The results show that states XcJ (J =0.2) decay into ∧(∧^-) pair with a larger branching ratio than into p(p^-) pair.展开更多
文摘Exclusive decays J/ψ(ψ') → Y(Y-) (Y = A,∑0, -) are studied in the quark model by combining thestructure of hyperons in the transition. The branching ratios are evaluated contrastively by adopting different hyperonwavefunctions, SU(6) basis, and uds basis, which account for SU(3)f breaking, and the results show that the differentdescription of quark mass breaking plays an important role in the evaluation of the decay width for processes J/ψ(ψ') →Y(Y-).
文摘We develop a method for calculation of the total reaction cross sections induced by the halo nuclei and stable nuclei. This approach is based on the Glauber theory, which is valid for nuclear reactions at high energies. It is extended for nuclear reactions at low energies and intermediate energies by including both the quantum correction and Coulomb correction under the assumption of the effective nuclear density distribution. The calculated results of the total reaction cross section induced by stable nuclei agree well with 30 experimental data within 10 percent accuracy.The comparison between the numerical results and 20 experimental data for the total nuclear reaction cross section induced by the neutron halo nuclei and the proton halo nuclei indicates a satisfactory agreement after considering the halo structure of these nuclei, which implies quite digerent mean fields for the nuclear reactions induced by halo nuclei and stable nuclei. The halo nucleon distributions and the root-mean-square radii of these nuclei can be extracted from the above comparison based on the improved Glauber model, which indicates clearly the halo structures of these nuclei. Especially,it is clear to see that the medium correction of the nucleon-nucleon collision has little effect on the total reaction cross sections, induced by the halo nuclei due to the very weak binding and the very extended density distribution.
文摘A quark pair creation model is introduced to study the XeJ exclusive decays into baryon-antibarvon pairs.The decay widths for processes Xcj→B(B^-) (J=0, 2;B=∧,∑^0,Ξ^-) are evaluated phenomenologically with an explicit inclusion of the properties for outgoing baryons described by wave functions in the naive quark model. The results show that states XcJ (J =0.2) decay into ∧(∧^-) pair with a larger branching ratio than into p(p^-) pair.
