Related papers: Extraction of $V_{ub}$ from the Decay $B\to \pi l …
Resummation of large QCD radiative corrections, including leading and next-to-leading logarithms, in pion electromagnetic form factor is reviewed. Similar formalism is applied to exclusive processes involving heavy mesons, and leads to…
We compute various form factors involved in $B\to D^{(*)}$ transitions based on the perturbative QCD formalism, which includes Sudakov effects from the resummation of large radiative corrections in a heavy-light system. A two-parameter…
We examine the applicability of perturbative QCD to $B$ meson decays into $D$ mesons. We find that the perturbative QCD formalism, which includes Sudakov effects at intermediate energy scales, is applicable to the semi-leptonic decay $B\to…
The modified perturbative approach in which transverse degrees of freedom as well as Sudakov suppressions are taken into account, is applied to $B$ decays into two $\pi$ mesons. The influence of various model parameters (CKM matrix…
The element |V_{ub}| of the quark mixing matrix can be extracted with small theoretical uncertainties by combining weighted integrals over the endpoint regions of the lepton spectrum in B -> X_u l nu decays and the photon spectrum in B ->…
We revisited the extracting $\left|V_{ub}/V_{cb}\right|$ and $|V_{ub}|$ through calculating the ratios ${\cal B}(B^0\to D_s^{(*)+}(\pi^-,\rho^-)/ {\cal B}(B^0\to D_s^{(*)+} D^{(*)-})$ in the perturbative QCD approach, which is regarded as…
We present a lattice QCD calculation of $B\to \pi l \nu$ semileptonic decay form factors in the small pion recoil momentum region. The calculation is performed on a quenched $16^3 \times 48$ lattice at $\beta=5.9$ with the NRQCD action…
We study $B\to \pi\pi$ decay with a modified perturbative QCD approach. The branching ratios and $CP$ violation are calculated with the transverse momenta of partons considered. Sudakov factor associated with each meson is included to…
The increasing accuracy of experimental results for the exclusive, semileptonic decay B -> pi l nu requires a similarly accurate calculation of the hadronic matrix elements, to determine |Vub|. We present preliminary results for the form…
We present results for the semi-leptonic and leptonic decays of B mesons. These non-perturbative matrix elements are important for constraining the CKM matrix. Results are presented for the pseudoscalar and vector decay constants, as well…
The exclusive semileptonic decay $B \rightarrow \pi \ell \nu$ is a key process for the determination of the Cabibbo-Kobayashi-Maskawa matrix element $V_{ub}$ from the comparison of experimental rates as a function of $q^2$ with…
We present our study on $B \to \pi l \nu$ semileptonic decay form factors with NRQCD action for heavy quark from a quenched lattice QCD simulation at $\beta$=5.9 on a $16^3\times 48$ lattice. We obtain form factors defined in the context of…
Theoretical predictions for B decay rates are rewritten in terms of the Upsilon(1S) meson mass instead of the b quark mass, using a modified perturbation expansion. The theoretical consistency of this expansion is shown both at low and high…
We evaluate the form factors describing the exclusive decay B-> pi l nu by using a Constituent Quark-Meson model based on an effective quark-meson Lagrangian (CQM). The model allows for an expansion in the pion momenta and we consider terms…
We derive a new factorization relation for the semileptonic radiative decay B -> \pi \ell \nu \gamma in the kinematical region of a slow pion p_\pi ~ \Lambda and an energetic photon E_\gamma >> \Lambda, working at leading order in…
We construct several classes of hadronic matrix elements and relate them to the low-energy constants in Chiral Perturbation Theory that describe the electromagnetic effects in the semileptonic beta decay of the pion and the kaon. We propose…
We present a quenched calculation of the form factors of the semileptonic weak decay $B \to \pi l \bar{\nu}$ with $O(1/m_Q)$ NRQCD heavy quark and Wilson light quark on a $16^3 \times 32$ lattice at $\beta=5.8$. The form factors are…
We calculate the $B\to P$, $B\to V$ (P: light pseudoscalar meson, V light vector meson) form factors in the large-recoil limit in perturbative QCD approach, including both the vector (axial vector) and tensor operators. In general there are…
The hadronic mass distribution in semileptonic B-meson decays can be used for extracting the charmless part and thus determining the |V_ub/V_cb| ratio. We take into account first-order perturbative as well as non-perturbative QCD…
We report on a calculation of form factors for the semileptonic decay of $B$ meson to pion on $2+1$-flavour lattices with lattice spacings from 0.080 fm down to 0.044 fm. Using the M\"obius domain wall fermion action for both sea and…