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Within the framework of the perturbative quantum chromodynamics(PQCD) approach, we study the charmless two-body decays B → a1(1260)K*, b1(1235)K*. Using the decay constants and the light-cone distribution amplitudes for these mesons derived from the QCD sum rule method, we find the following results.(a) Our predictions for the branching ratios are consistent with the QCD factorization(QCDF) results within errors, but much larger than the naive factorization approach calculation values.(b) We predict that the anomalous polarizations occurring in the decays B→φK*, ρK*also happen in B→a1 K*decays, while they do not happen in B→b1 K*decays. Here the contributions from the annihilation diagrams play an important role in explaining the larger transverse polarizations in the B→a1 K*decays, while they are not sensitive to the polarizations for the B→b1 K*decays.(c) Our predictions for the direct C P-asymmetries agree well with the QCDF results within errors. The decaysˉB0→b1+K*-, B-→b10K*-have larger direct C P-asymmetries, which could be measured by the present LHCb experiment and the forthcoming Super-B experiment. 相似文献
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采用浸渍技术,分别以新鲜和老化两组硅纳米孔柱阵列(Si-NPA)衬底为模板制备了不同形貌特征的Au/Si-NPA.结果表明:造成两组衬底上形成的Au/Si-NPA形貌上的巨大差异主要是由于两组Si-NPA衬底表面氧含量的分布不同所致.进一步分析发现,Si-NPA在Au/Si-NPA的形成过程中既起到了模板作用,又起到了还原的双重作用.由于Si-NPA具有规则的阵列结构,从而使得金在Si-NPA表面上的沉积速率产生选择性,最终可以形成准周期的、规则的金纳米复合薄膜. 相似文献
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