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The nonleptonic two body Bu,d,s,c decays involving a light tensor meson in final states are studied in the perturbative QCD approach based on kT factorization. The decay modes with a tensor meson emitted, are prohibited in naive factorization, since the emission diagram with a tensor meson produced from vacuum is vanished. While contributions from the so-called hard scattering emission diagrams and annihilation type diagrams are important and calculable in the perturbative QCD approach. The branching ratios of most decays are in the range of 10-4-10-8, which are bigger by 1 or 2 orders of magnitude than the predictions given by the naive factor- ization, but consistent with the predictions from the QCD factorization and the recent experimental measurements. We also give the predictions for the direct CP asymmetries, some of which are large enough for the future experiments to measure. We also find that, even with a small mixing angle, the mixing between f2 and f′2 can bring remarkable changes to both branching ratios and the direct CP asymmetries for some decays involving f2(′) mesons. For decays with a vector meson and a tensor meson in final states, we predict a large percentage of transverse polarization contributions due to the contributions of the orbital angular momentum of the tensor mesons. 相似文献
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徐晓梅 《云南大学学报(自然科学版)》1998,20(4):259-261
研究了HERA分解光生过程中的J/ψ产生.结果表明该过程可以用来测量光子及质子中的部分子分布,也可以用于测量胶子和重夸克的J/ψ碎裂机制以检验微扰QCD. 相似文献
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