Related papers: The Isgur-Wise function in a relativistic model fo…
We extend our recent work, in which the Dirac equation with a ``(asymptotically free) Coulomb + (Lorentz scalar $\gamma_0\sigma r$) linear '' potential is used to obtain the light quark wavefunction for $q\bar Q$ mesons in the limit $m_Q\to…
We have studied the weak decay constants and the Isgur-Wise form factor of the B and D mesons in the heavy quark limit, by employing a relativistic quark confinement model. It is an attempt to improve our previous work within the same line…
We present a general formalism that uses the point form of relativistic Hamiltonian dynamics to describe the electroweak structure of heavy-light mesons within constituent quark models. We study the heavy quark limit (i.e. $m_Q\to \infty$)…
The original de Rafael-Taron bound on the slope of the Isgur-Wise function at zero recoil is known to be violated in QCD by singularities appearing in an unphysical region. To be consistent, quark models must have corresponding singularity…
The exclusive semileptonic decay Lambda_b -> Lambda_c + l nu_l is investigated including both radiative and first-order power corrections in the inverse heavy-quark mass, while the Isgur-Wise function is calculated within a light-front…
We present an investigation of the Isgur-Wise form factor relevant for the semileptonic decay Lambda_b -> \Lambda_c + l nu_l performed within a light-front constituent quark model. Adopting different baryon wave functions it is found that…
In the heavy quark limit of QCD, using the Operator Product Expansion and the non-forward amplitude, as proposed by Nikolai Uraltsev, we formulate sum rules that generalize Bjorken and Uraltsev sum rules. We recover the Uraltsev lower bound…
Nambu-Goto action of bosonic string predicts the quark-antiquark potential to be $ V (r) = \frac{\gamma}{r} + \sigma r +\mu_0 $. The coefficient$ \gamma = - \frac{\pi(d-2)}{24} $ is the universal L\"{u}scher coefficient of the L\"uscher…
Diffractive dissociation of particles can be used to study their light-cone wave functions. Results from Fermilab experiment E791 for diffractive dissociation of 500 GeV/c pi- mesons into di-jets show that the |q qbar> light-cone asymptotic…
We present preliminary results for various electroweak form factors of pseudo-scalar mesons using the tree-level improved Symanzik gauge action and the maximally twisted mass fermionic action with Nf = 2 dynamical flavors. Our results,…
Nambu-Goto action for bosonic string predicts the quark-antiquark potential to be $V(r) = -\frac{\gamma}{r}+ \sigma r + \mu_0$. The coefficient $\gamma=\frac{\pi(d-2)}{24}$ is the L\"{u}scher coefficient of the L\"{u}scher term…
The Isgur-Wise function vastly reduces the weak-decay form factors of hadrons containing one heavy quark. In this paper, we extract the Isgur-Wise functions from the instantaneous Bethe-Salpeter method, and give the numerical results for…
In quark models \`a la Bakamjian and Thomas, that yield covariance and Isgur-Wise scaling of form factors in the heavy quark limit, we compute the decay constants $f^{(n)}$ and $f^{(n)}_{1/2}$ of S-wave and P-wave mesons composed of heavy…
Diffractive dissociation of particles can be used to study their light-cone wave function. Results from Fermilab experiment E791 for diffractive dissociation of 500 GeV/c $\pi^-$ mesons into di-jets are presented. The results show that the…
In this paper we construct a covariant light-front model of heavy mesons within the framework of heavy quark effective theory (HQET). The covariant model consists of the light-front heavy meson bound states constructed in the heavy quark…
We present preliminary results from simulations done on 170 $32^3 \times 64$ lattices at $\beta = 6.0$ using quenched Wilson fermions. This talk focuses on the $Q^2$ behavior of the form-factors, extrapolation in quark masses, dependence on…
We consider the NJL model as an effective quark theory to describe the interaction which is responsible for the quark flavor dynamics at intermediate energies. In addition to the usual ultraviolet cut-off which is necessary since the model…
The heavy quark effective theory makes model independent predictions for semileptonic $\Lambda_b \to \Lambda_c$ decays in terms of a small set of parameters. No subleading Isgur-Wise function occurs at order $\Lambda_{\rm QCD}/m_{c,b}$, and…
We use the vacuum expectation value of a Wegner-Wilson loop representing a fast moving quark-antiquark pair to derive the light cone Hamiltonian for a $q\bar q$ meson. We solve the corresponding Schr\"odinger equation for various trial wave…
In this article, we use the light-cone QCD sum rules to relate the $\Lambda_b$ baryon light-cone distribution amplitudes to the Isgur-Wise function $\xi(\omega)$ of the $\Lambda_b \to \Lambda_c$ transition, and obtain a simple relation. The…