相关论文: B->gamma e nu Transitions from QCD Sum Rules
Using the renormalon calculus, we study the asymptotic behavior of the perturbative expansion of the hard-scattering kernels entering the QCD factorization formula for the nonleptonic weak decays B->D M, where M is a light meson. In the…
This thesis examines the applications and determinations of meson light-cone distribution amplitudes. The investigation of such processes, in the context of $B$ physics, provides one with a rich and extensive way of determining the Standard…
We investigate the inverse moment of the $B_s$-meson light-cone distribution amplitude (LCDA), denoted as $\lambda_{B_s}$ and defined within the heavy quark effective theory, through the calculation of $B_s \to \eta_s$ form factors. The…
The accurate calculation of weak heavy-to-light form factors is crucial for the determination of CKM matrix elements from experimental data on B decays. In SCET, the soft-collinear effective theory, these form factors can, in the heavy…
We derive a factorization theorem for the structure-dependent QED effects in the weak exclusive process $B^-\to\ell^-\bar\nu_\ell$, i.e., effects probing the internal structure of the $B$ meson. The derivation requires a careful treatment…
We study the first power correction to the heavy electron form factor in QED and show that it factorizes as a derivative operator. We discuss the result in QED with no light fermions, where the first power correction can be written…
We present results for the $B \rightarrow \pi$ and $D\rightarrow \pi$ form factors derived from QCD sum rules on the light-cone. Our predictions are compared with experiment and used to extract the quark mixing parameter $|V_{ub}|$ from a…
Within the framework of QCD light-cone sum rules (LCSR), we calculate the form factor for $B{\to}D l\tilde{\nu}$ transitions with chiral current correlator. The resulting form factor depends on the distribution amplitude(DA) of the…
The form factors of the semileptonic $B_c\to S(AV)\ell\nu$ $(\ell=\tau, \mu, e)$ transitions, where S and AV denote the scalar $X_{c0}$ and axial vector $(X_{c1}, h_{c})$ mesons, are calculated within the framework of the three-point QCD…
We use three-point function QCD sum rules to calculate the form factor $A_0(q^2)$ appearing in the matrix element of the flavour-changing axial current between the $D (B)$ state and a vector meson state. We describe the role of this form…
We examine the B -> D* form factor at zero recoil using a continuum QCD approach rooted in the heavy quark sum rules framework. A refined evaluation of the radiative corrections as well as the most recent estimates of higher order power…
We investigate sum rules for heavy-to-light transition form factors at large recoil derived from correlation functions with interpolating currents for light pseudoscalar or vector fields in soft-collinear effective theory (SCET). We…
I discuss the two-particle subleading power corrections in radiative leptonic $B \to \gamma \ell \nu$ decay at next-to-leading order in $\alpha_s$ with the dispersion approach. Employing the method of regions, factorization of the $B \to…
In the framework of the soft-collinear effective theory, we demonstrate that the leading-power heavy-to-light baryonic form factors at large recoil obey the heavy quark and large energy symmetries. Symmetry breaking effects are suppressed…
Applying the method of light-cone sum rules with photon distribution amplitudes, we compute the subleading-power correction to the radiative leptonic $B \to \gamma \ell \nu$ decay, at next-to-leading order in QCD for the twist-two…
The transition gamma*(q_1)gamma*(q_2) -> \pi0(p) is studied within the QCD sum rule framework. As a first step, we analyze the kinematic situation when both photon virtualities are spacelike and large. We construct a QCD sum rule for…
We compute the O(1/M,m_s) heavy quark and SU(3) corrections to B_s -> D_s e nu form factors. In the limit of vanishing light quark mass, B_s -> D_s e nu form factors are given in terms of the the B -> D e nu form factors, the leading order…
We compute the form factors parametrizing radiative leptonic decays of heavy mesons B^+\to\gamma e^+\nu for photon energies much larger than \Lambda_{QCD}, where perturbative QCD methods for exclusive processes can be combined with the…
Based on a new, exact QCD factorization formula for the partial B->X_s+gamma decay rate with a restriction on large photon energy, improved predictions are presented for the partial moments <E_gamma> and <E_gamma^2>-<E_gamma>^2 of the…
We derive factorization theorems for Lambda_QCD/mb power corrections to inclusive B-decays in the endpoint region, where mX^2 ~mb Lambda_QCD. In B-> Xu e nu our results are for the full triply differential rate. A complete enumeration of…