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21.
In this paper, we calculate the branching ratios of Λb→pK- and pπ- decays in the avor changing Z' model. We nd that the branching ratios for these two decay modes are sensitive to the contributions of the Z' boson. For Λb→pK- decay, if the left-handed couplings are equal to the right-handed couplings, the branching ratio of this decay could match up to the currently experimental data for ξs=0.01 and -52°<φsL<132°, or ξs=0.004 and 0°<φsL<84°; if only the left-handed couplings are considered, it could match up to the experimental data for ξs=0.01 and -10°φsL<138°. And for Λb→pK- decay, if the left-handed and right-handed couplings are equal, the branching ratio of Λb→pK- decay may be consistent with the currently experimental data with ξd=0.05 and -135°φdL<43°, if only the left-handed couplings are considered, it may be consistent with ξd=0.05 and -114°φdL<8°.  相似文献   
22.
We study the pure leptonic decays Bs,d →μ+μ- in a Flavor Changing Z′ Model.From the recent measurements of the branching ratios B(Bs,d →μ+μ-),we have derived the bounds on the effective μ-μ-Z′ lepton coupling BμLμ.We find that,(i) if neglecting the contribution from the right-handed lepton coupling BμRμ,we obtain 1.32 < BμLμ < 3.32;(ii) if considering the contribution from the right-handed lepton coupling BμRμ and setting BμLμ =BμRμ,we obtain 0.99相似文献   
23.
黄金书  罗鹏晖  鲁公儒 《物理学报》2009,58(12):8166-8173
计算了顶色辅助人工色模型对光子对撞机上底夸克对产生过程的Yukawa 修正.发现在合理的参数范围内,赝标量Goldstone 玻色子引起的相对修正与树图水平相比有3.17% 到5.90% 的压低.该结果明显地大于标准模型、双Higgs 二重态模型和最小超对称模型中的相应贡献. 这样的修正对于正在设计中的国际直线对撞机上检验标准模型和探索新物理是很有意义的. 关键词: 顶色辅助人工色模型 光子对撞机 散射截面  相似文献   
24.
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.  相似文献   
25.
考虑了一代人工色(OGTC)模型和topcolor援助的多标度人工色(TOPCMTC)模型中的规范玻色子对Wtb耦合的贡献。发现对角ETC玻色子的交换对Wtb耦合没有直接贡献,运用LEP给出的Rb的数值,发现对于一定范围内的参数值来说,OGTC模型中的ETC规范玻色子交换和TOPCMTC模型中的ETC规范玻色子交换和colorn交换对CKM矩阵元Vtb的贡献都是相当大的,Vtb可能被费米实验室TevatronRun3探测到。  相似文献   
26.
We study the effects of the fourth quark generation model in ■_s →π-K+decay.Combining with the up-to-date experimental measurement for B(■_s →π-K +) and A dir cp(■_s →π-K +) by the CDF Collaboration,we derive the new bound of weak phase φ bd,which are 0 < φ bd < 44,321 < φ bd < 360 and 0 < φ bd < 26,342 < φ bd < 360 for m t = 400 and 600 GeV respectively.In these regions,B(■_s →π-K +) and A dir cp(■_s →π-K +) consist with the current experimental data within errors.  相似文献   
27.
In this paper, we calculate the production of a charged top pion in association with a W boson via gg fusion at CERN's Large Hadron Collider in the context of the topcolor assisted technicolor model. We find that the total cross section of pp → gg → W±πt is several dozen femtobarns with reasonable values of the parameters, and the total cross section of pp → W±πt can reach a few hundred femtobarns when we consider the sum of the contributions of these two parton subprocesses, gg → W±πt and bb → W±πt.  相似文献   
28.
We study the effects of the fourth quark generation model in Bs → π-K+ decay. Combining with the up-to-date experimental measurement for B(Bs → π-K+) and Acpdir(Bs → π-K+) by the CDF Collaboration, we derive the new bound of weak phase øbd, which are 0°< øbd <44°, 321°< øbd < 360° and 0°< øbd < 26°, 342°< øbd < 360° for mt'=400 and 600 GeV respectively. In these regions, B(Bs → π-K+) and Acpdir(Bs → π-K+) consist with the current experimental data within errors.  相似文献   
29.
课堂是教师教学的主阵地,课程是人才培养的重要载体.文章结合《中学物理教学技能与教学设计》的建设,从课程定位、教学内容、教学模式、教学评价等方面,介绍了精品资源共享课的建设和体会.  相似文献   
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