Related papers: Calculation of coupling constant g_phi-pi-gamma in…
The method of QCD sum rules at finite temperature is reviewed, with emphasis on recent results. These include predictions for the survival of charmonium and bottonium states, at and beyond the critical temperature for de-confinement, as…
We use an appropriate combination of moments of finite energy sum rules in QCD in order to compute the B_q-meson decays constants f_B and f_{B_s}.We perform the calculation using a two-loop computation of the imaginary part of the…
We use the method of QCD sum rules in the presence of an external pion field to investigate isospin symmetry breakings in pion-nucleon couplings. Possible manifestations of such isospin symmetry breaking are examined in the context of…
We calculate the pion decay constant near the critical temperature of the $O(N)$ nonlinear sigma model in the large $N$ limit. Making use of the known low temperature behavior, we construct a Pad\'{e} approximant to obtain the behavior of…
Motivated by the recent work on the calculation of the $\pi NN$ coupling constant using QCD sum rule beyond the chiral limit, we construct the corresponding sum rules for the couplings, $\eta NN$, $\pi \Xi\Xi$, $\eta \Xi\Xi$, $\pi \Sigma…
I discuss the calculation of the direct CP-asymmetry in $D\to \pi^+\pi^-$ and $D\to K^+K^- $ decays with the method of QCD light-cone sum rules. The main result is the upper limit for the difference of the two asymmetries $\left|\Delta…
We look at two methods to determine the weak phases $\phi_2$ and $\phi_3$ from $B \to \pi\pi$ and $K\pi$ decays within the perturbative QCD approach. We obtain quite interesting bounds on $\phi_2$ and $\phi_3$ from recent experimental…
We investigate the properties of heavy quarkonia at finite temperature in detail using QCD sum rules. Extending previous analyses, we take into account a temperature dependent effective continuum threshold and derive constraints on the…
We present the results of our lattice QCD study of the $g_{D^* D\pi}i$ coupling, relevant to the $D^\ast \to D\pi$ decay. Our computation is made on the gauge field configurations that include $N_f=2$ dynamical light quarks by using the…
The method of light-cone QCD sum rules is applied to the calculation of the form factors of $\gamma^*\rho \to \pi$ and $\gamma^*\gamma \to \pi^0$ transitions. We consider the dispersion relation for the $\gamma^*(Q^2)\gamma^*(q^2) \to…
We look at two methods to determine the weak phases $\phi_2$ and $\phi_3$ from $B \to \pi\pi$ and $K\pi$ decays within the perturbative QCD approach. We obtain quite interesting bounds on $\phi_2$ and $\phi_3$ from experimental measurements…
Over 40 years after the calculation of the 1-loop QED corrections to the muon lifetime, new theoretical developments have made it possible to obtain an analytic expression for the complete 2-loop QED contributions in the Fermi theory. The…
We present a non-perturbative calculation for the pion decay constant with quenched Kogut-Susskind quarks. Numerical simulations are carried out at $\beta = 6.0$ and 6.2 with various operators extending over all flavors. The renormalization…
A visible improvement of the QCD sum-rule framework, achieved only recently by a slightly more sophisticated consideration of the hadron excitations and continuum, is applied to the extraction of the decay constants of heavy-light…
Properties of the pion are studied at finite temperature with the help of the PCAC and the QCD sum rule. The pionic mode is treated consistently with the thermal pions which consist of the ground state at finite temperature. The temperature…
Using QCD sum rules, we compute the diagonal meson-baryon couplings, $\pi NN$, $\eta NN$, $\pi \Xi\Xi$, $\eta \Xi\Xi$, $\pi \Sigma \Sigma$ and $\eta \Sigma \Sigma$, from the baryon-baryon correlation function with a meson, $i\int d^4x…
In this comment, we propose possible errors in constructing the continuum contribution in the sum rule studied by M. C. Birse and B. Krippa, Phys. Rev. C. {\bf 54} (1996) 3240.
We calculate the transition form factor for the 'B_c -> B_u^* gamma' decay taking into account only the short distance contribution, in framework of QCD sum rules method. We observe that the transition form factor predicted by the QCD sum…
Using the method of QCD light-cone sum rules, we calculate the $B \to \pi\pi$ hadronic matrix elements with annihilation topology. We obtain a finite result, including the related strong phase. Numerically, the annihilation effects in $B\to…
We discuss the extraction of ground-state parameters, such as decay constants and form factors, from two- and three-point dispersive sum rules, making use of a quantum-mechanical potential model. This model provides a unique possibility to…