120157276
Infrared divergence and twist-3 wave functions in QCD factorization for B -> PP decays
The problem of chirally enhanced corrections for B decays into two light pseudoscalars in QCD factorization scheme is discussed. We find that the infrared divergences of the vertex corrections cancel only if the twist-3 Wave functions are symmetric. In that case chirally enhanced corrections can be included consistently. The divergences appeared in the hard spectator scattering are also discussed briefly.
120258823
The Renormalization of the effective gauge Lagrangian with spontaneous symmetry breaking: the SU(2) x U(1) case
123435703
UNIFIED MODEL OF METACOLOR INTERACTION
Unified composite model in which the metacolor symmetry group and the standard model group are embedded in a single group of the SU(N) type and unified above a certain energy scale are constructed. Such unification scheme provides constraints to the composite model building. The proposed models are analyzed in terms of the complementarity principle to show that they satisfy the physics Higgs phase criterion. In order to obtain a metacolor scale of the order of a few tens TeV, the rank of the unification group is restricted.
15707587
Study of $B_c \to J/psi\pi^-, \eta_c\pi^-$ decays with QCD factorization
The $B_{c}$ ${\to}$ $J/{\psi}{\pi}$, ${\eta}_{c}{\pi}$ decays are studied in the scheme of the QCD factorization approach. The branching ratios are calculated with the asymptotic distribution amplitude of the pion. The charm quark mass effect is considered. We find that the mass effect on the branching ratios is small.
9074908
Brane fluctuation and the electroweak chiral Lagrangian
We use the external field method to study the electroweak chiral Lagrangian of the extra dimension model with brane fluctuation. Under the assumption that the contact terms between the matter of the standard model and Kaluza-Klein (KK) excitations of the bulk gauge fields are heavily suppressed, we use the standard procedure to integrate out the quantum fields of these KK excitations and the equation of motion to eliminate the classic fields of these KK excitations. At the one-loop level, we find that up to the order ${O(p}^{4}),$ due to the momentum conservation of the fifth dimension and the gauge symmetry of the zero modes, there is no constraint on the size of the extra dimension. This result is consistent with the decoupling theorem. However, meaningful constraints can come from those operators in ${O(p}^{6})$ which can contribute considerably to some anomalous vector couplings and can be accessible at the 500 GeV linear collider and the CERN Large Hadron Collider.
15449960
QCD Factorization For B Decays To Two Light Pseudoscalars Including Chirally Enhanced Corrections
Since b quark mass is not asymptotically large, chirally enhanced corrections which arise from twist-3 wave functions may be important in B decays. We thus evaluate the hadronic matrix elements with the emitted meson described by leading twist and twist-3 distribution amplitudes $\Phi_p(x)$. After summing over the four "vertex correction" diagrams, we obtain the results with infrared finiteness which shows that chirally enhanced corrections arise from $\Phi_p(x)$ can be consistently included in QCD factorization. We also briefly discuss the contributions from "hard spectator" diagrams.
13450120
Quasinormal modes in pure de Sitter spacetimes
We have studied scalar perturbations as well as fermion perturbations in pure de Sitter spacetimes. For scalar perturbations we have shown that well-defined quasinormal modes in d-dimensions can exist provided that the mass of scalar field m>(d-1/2l). The quasinormal modes of fermion perturbations in three and four dimensional cases have also been investigated. We found that different from other dimensional cases, in the three dimensional pure de Sitter spacetime there is no quasinormal mode for the s-wave. This interesting difference caused by the spacial dimensions is true for both scalar and fermion perturbations.