Related papers: New results on Pionic Twist-3 Distribution Amplitu…
The $q^2$ dependence of the $\pi$-$\eta$ mixing amplitude is examined with the use of QCD sum rules. The linear slope of the mixing function $\theta(q^2)$ is found to be much smaller than that for $\rho$-$\omega$ mixing. Thus the mixing…
Employing the standard hard-scattering approach and the running coupling method we calculate a class of power-suppressed corrections $\sim 1/Q^{2n},n=1,2,3,...$ to the electromagnetic $\pi^0\gamma$ transition form factor (FF)…
We discuss the end-point behavior of the pion distribution amplitude (DA) and calculate its slope using QCD sum rules with nonlocal condensates. This is done in terms of the standard derivative and also with the help of an "integral…
The isospin-singlet scalar meson $f_0(980)$ is hypothesized to consist of two energy eigenstates, forming a mixture of $\frac{1}{\sqrt{2}}(\bar{u}u + \bar{d}d)$ and $\bar{s}s$. Building on this framework, we apply the QCD sum rules approach…
In this article, we study the $B \to K^*_2(1430)$, $a_2(1320)$, $f_2(1270)$ form-factors with the light-cone QCD sum rules, where the $B$-meson light-cone distribution amplitudes are used. In calculations, we observe that the line-shapes of…
The QCD evolution of the pion distribution amplitude (DA) $\phi_\pi(x,Q^2)$ is computed for several commonly used models. Our analysis includes the nonperturbative form predicted by light-front holographic QCD, thus combining the…
We describe the present status of the pion distribution amplitude as it originated from two sources: (i) a nonperturbative approach, based on QCD sum rules with nonlocal condensates and (ii) a NLO QCD analysis of the CLEO data on…
We analyze $F_\pi(Q^2)$ and $F_{P\gamma}(Q^2)$, $P=\pi,\eta,\eta'$, within the local-duality (LD) version of QCD sum rules, which allows one to obtain predictions for hadron form factors in a broad range of momentum transfers. To probe the…
We have analyzed the $B\to \pi $ and $B_{s}\to K$ semileptonic form factors and $B\to V\gamma (V=K^*,\rho,\omega)$ processes in the light-cone QCD sum rules. In order to enhance the predictivity and reliability of numerical results the…
We present an investigation of the electromagnetic pion form factor, $F_\pi(Q^2)$, at small values of the four-momentum transfer $Q^2$ ($\lesssim 0.25$ GeV$^2$), based on the gauge configurations generated by European Twisted Mass…
In this paper, we study the leading-twist distribution amplitude (DA) of the heavy pseudoscalars (HPs), such as $\eta_c$, $\eta_b$ and $B_c$, within the QCD theory in the background fields. New sum rules up to dimension-six condensates for…
A model field theory, in which the interaction between quarks is mediated by dressed vector boson exchange, is used to analyse the pionic sector of QCD. It is shown that this model, which incorporates dynamical chiral symmetry breaking,…
We compute the pion light-cone wave function and the pion quark distribution amplitude in the Nambu-Jona-Lasinio model. We use the Pauli-Villars regularization method and as a result the distribution amplitude satisfies proper normalization…
The $^{1}$H($e,e^\prime \pi^+$)n cross section was measured for a range of four-momentum transfer up to $Q^2$=3.91 GeV$^2$ at values of the invariant mass, $W$, above the resonance region. The $Q^2$-dependence of the longitudinal component…
Based on sum rules, we explore the twist-2 distribution amplitude of the $K_0^*(1430)$ meson, treating it as the ground state of a quark-antiquark system. We posit that the spacetime distance $x$ should be infinitesimally close to the quark…
We provide a theoretical update of the calculations of the pi0-gamma*-gamma form factor in the LCSR framework, including up to six polynomials in the conformal expansion of the pion distribution amplitude and taking into account twist-six…
In a recent paper [1] we have proposed a new approach for extracting the wave function of the $\pi$-meson $\varphi_{\pi}(x)$ and the masses and wave functions of its first resonances from the new QCD sum rules for non-diagonal correlators…
Sum rules for twist-3 distributions are reexamined. Integral relations between twist-3 and twist-2 parton distributions suggest the possibility for a $\delta$-function at $x=0$. We confirm and clarify this result by constructing $h_L$ and…
pi pi scattering at low energy is sensitive to the structure of the QCD vacuum. I review the calculations of the pi pi scattering lengths and phases, and group them in three cathegories: 1. those based on very general theoretical…
The pion distribution amplitude (DA) can be related to the fundamental QCD Green's functions as a function of the quark self-energy and the quark-pion vertex, which in turn are associated with the pion wave function through the…