相关论文: Asymptotics of Heavy-Meson Form Factors
We present the first lattice-QCD calculation of the form factors governing the charm-baryon semileptonic decays $\Lambda_c \to \Lambda^*(1520)\ell^+\nu_\ell$. As in our previous calculation of the $\Lambda_b \to \Lambda^*(1520)$ form…
We underline the general features of the constituent quark model and its success in the description of the spectrum and transitions of hadrons made up of light or heavy quarks, briefly compared to first principles of QCD. To show the…
The $\eta^{(\prime)}$-mesons in the quark-flavor basis are mixtures of two mesonic states $|\eta_{q}\rangle=|\bar u u+\bar d d\rangle/\sqrt 2$ and $|\eta_{s}\rangle=|\bar s s\rangle$. In the previous work, we have made a detailed study on…
We provide upper and lower bounds on the semileptonic weak decay form factors for $B \to D^(*)$ and $\Lambda_b \to \Lambda_c$ decays by utilizing inclusive heavy quark effective theory sum rules. These bounds are calculated to second order…
We derive a factorization formula for boosted double resonant top-antitop pair production in $e^+e^-$ annihilation with a semileptonic top quark decay in the phase space region where the $b$-jet invariant mass is small. The decaying top…
In large-momentum effective theory (LaMET), the transverse-momentum-dependent (TMD) light-front wave functions and soft functions can be extracted from the simulation of a four-quark form factor and equal-time correlation functions. In this…
We propose a form factor approach for the computation of the large distance asymptotic behavior of correlation functions in quantum critical (integrable) models. In the large distance regime we reduce the summation over all excited states…
We study the analytic structure of light-front wave functions (LFWFs) and its consequences for hadron form factors using an explicitly Lorentz-invariant formulation of the front form. The normal to the light front is specified by a general…
Making use of the measurement of the $B\to K^*\gamma$ branching ratio together with the relations following from the limit of high recoil energy, we obtain stringent constraints on the values of the form-factors entering in heavy-to-light…
Using the analytic properties of two-point functions in QCD, as well as unitarity, bounds on the B meson form factor F(q^2) can be derived. Heavy quark spin symmetry, correctly taken into account, is shown to improve these bounds…
Assuming simple properties of the spectator particle in weak decays the form factors of hadronic current matrix elements are shown to be related to a single universal function. The Isgur-Wise result for heavy-to-heavy transitions follows as…
We use rigorous QCD dispersion relations to derive model-independent bounds on the B -> pi l nu, D -> pi l nu and D -> K l nu form factors. These bounds are particularly restrictive when the value of the observable form factor at one or…
The form factors of weak decays of the B meson to orbitally excited scalar, axial vector and tensor light mesons are calculated in the framework of the QCD-motivated relativistic quark model based on the quasipotential approach.…
We discuss applications of the dispersion quark model to exclusive semileptonic decays of heavy mesons. The transition form factors in this relativistic formulation of the quark model are given by double spectral representations through the…
An explicit model is presented which gives the momentum transfer-dependent ratios of form factors of hadronic currents. For the unknown Isgur-Wise function and its generalization for transitions to light particles a simple phenomenological…
Light-cone QCD sum rules to leading order in QCD are used to investigate the tensor form factors of the $\Sigma-\Sigma$, $\Xi-\Xi$ and $ \Sigma-\Lambda$ transitions in the range $1 GeV^2 \leq Q^2 \leq 10 GeV^2$. The DAs of $\Sigma$, $\Xi$…
The formfactors of B_1 -> pi and D_1 -> pi transitions, where B_1(D_1) is the 1^+ P-wave -> Q gamma_{\nu}\gamma_5q meson state, are calculated in the framework of the light cone QCD. Furthermore these formfactors are compared with the pole…
I review the QCD sum rules calculations of the form factors governing the semileptonic decays of charmed and beauty mesons. In particular, I discuss the predicted dependence of the various form factors on $q^2$ and how it can be obtained…
Semileptonic B decays are described by the Isgur-Wise form factor to the leading order in 1/m; four new functions appear in the first order [Luke]. Values of these functions are crucial for the applicability of the whole approach to…
We study in detail the kinematics of semileptonic $M_{l3}$ ($M \rightarrow M^\prime l \nu$) decay, considering only the new models preserving all the gauge symmetries of the Standard Model (SM), and assuming that neutrinos are massless and…