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The form factors and the coupling constant of the $B_s B^* K $ and $B_s B K^*$ vertices are calculated using the QCD sum rules method. Three point correlation functions are computed considering both the heavy and light mesons off-shell in…

High Energy Physics - Phenomenology · Physics 2015-05-20 A. Cerqueira , B. Osório Rodrigues , M. E. Bracco , M. Nielsen

The short-time regime of QCD two-point correlation functions is examined through a QCD-Sum-Rule-inspired continuum model. QCD Sum Rule techniques are tested and alternate nucleon interpolating fields are discussed. The techniques presented…

High Energy Physics - Lattice · Physics 2009-10-22 Derek B. Leinweber

We discuss the pion form factor calculation in QCD.We shortly consider the main points of the nonlocal condensate QCD sum rule approach and show its results for the pion form factor, $F_\pi(Q^2)$. These results are compared with predictions…

High Energy Physics - Phenomenology · Physics 2015-05-20 Alexander P. Bakulev

The radiative decays $ B^{*} (D^{*})\to B(D) \gamma$ are investigated in the framework of light cone QCD sum rules. The transition amplitude and decay rates are estimated.It is shown that our results on branching ratios of D meson decays…

High Energy Physics - Phenomenology · Physics 2015-06-25 T. M. Aliev , D. A. Demir , E. Iltan , N. K. Pak

The calculations of masses and decay constants of the radial excitations of light pseudoscalar and scalar mesons within QCD sum rules method are briefly reviewed. The predictions are based on the $1/N_c$-supported model spectra, which…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. L. Kataev

We compute the couplings $DD^*\pi$,$D_1D^*\pi$,$D^*D^*\pi$, $D_1 D_1\pi$ using QCD sum rules. These couplings are important inputs in the meson exchange model calculations used to estimate the amount of $J/\psi$ absorption due to pions and…

High Energy Physics - Phenomenology · Physics 2011-09-13 Hungchong Kim , Su Houng Lee

By matching the world of hadrons to that of some effective chiral quark theory, we determine the induced condensates for QCD sum rules in the presence of an external pion field. The observed values of the strong and weak $\pi NN$ coupling…

High Energy Physics - Phenomenology · Physics 2014-11-17 W-Y. P. Hwang

In this article, we study the contribution from the final-state interactions to the strong coupling constant $g_{D^* D \pi}$. We take an assumption that the momentum transfers in the strong decay $D^{*+} \to D^0 \pi^+$ be large to validate…

High Energy Physics - Phenomenology · Physics 2007-09-17 Zhi-Gang Wang

We use the QCD sum rules for the three point correlation functions to compute the strong coupling constants of the meson vertices $\eta_c D^* D$ and $\eta_c D_s^* D_s$. We consider perturbative and non-perturbative contributions, working up…

High Energy Physics - Phenomenology · Physics 2018-08-01 B. Osório Rodrigues , M. E. Bracco , C. M. Zanetti

Recently BES at BEPC found evidence for the existence of the $\sigma$ meson in the process of $J/\Psi \to \sigma\omega \to\pi\pi\omega$. In this paper we firstly discuss the relevant coupling $g_{\sigma\pi\pi}$ and show that the linear…

High Energy Physics - Phenomenology · Physics 2009-11-07 Wujun Huo , Xinmin Zhang , Tao Huang

The nucleon axial coupling constant $g_A$ is calculated in the presence of an external uniform magnetic field using finite energy sum rules. The correlation function of proton, neutron and axial-vector currents is calculated both the…

High Energy Physics - Phenomenology · Physics 2023-04-12 Cristián Villavicencio

QCD sum rules on the light-cone are derived for the sum $f^+ + f^-$ of the $B\to \pi$ and $D\to \pi$ form factors taking into account contributions up to twist four. Combining the results with the corresponding $f^+$ form factors calculated…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. Khodjamirian , R. Rückl , C. W. Winhart

QCD sum rules are used to calculate the $q^2$ dependence of the $\pi NN$ coupling $g_{\pi NN} (q^2)$ in the spacelike region $0.5 \ {\mbox{GeV}}^2 \lesssim q^2 \lesssim 1.5\ {\mbox{GeV}}^2$. We study the Borel sum rule for the three point…

Nuclear Theory · Physics 2008-11-26 Thomas Meissner

We give sum rules for tetraquark decay coupling constants, taking into account the SU(3) symmetry breaking interactions to first order.

High Energy Physics - Phenomenology · Physics 2013-04-05 V. Gupta , G. Sánchez-Colón , S. Rajpoot

I demonstrate that the short distance contribution to K --> Pi Pi decays must be supplemented with large distance effects. A hybrid calculation is outlined based on QCD diagrams supplemented by chiral contributions and Pi-Pi phaseshifts.

High Energy Physics - Phenomenology · Physics 2007-05-23 E. A. Paschos

We work out the method for evaluating the QCD coupling constant at finite temperature ($T$) by making use of the finite $T$ renormalization group equation up to the one-loop order on the basis of the background field method with the…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Chaichian , M. Hayashi

We review some recent applications of QCD sum rules to $B$-decays. These include the determination of the leptonic constant $f_B$ and of the semileptonic transition amplitudes of the $B$-meson into negative and positive parity charmed…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Colangelo , G. Nardulli , N. Paver

The pion and kaon electromagnetic form factors $F_M(Q^2)$ are calculated at the leading order of pQCD using the running coupling constant method. In calculations the leading and next-to-leading order terms in $\alpha_S((1-x)(1-y)Q^2)$…

High Energy Physics - Phenomenology · Physics 2009-10-31 Shahin S. Agaev

The radiative decay $ B_{q}^*\to B_{q}\gamma(q=u,d, or s) $ is reexamined with a modified light-cone QCD sum rule method, in which adequate chiral operators are chosen as the interpolating fields in the correlators used for a sum rule…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zuo-Hong Li , Xiang-Yao Wu , Tao Huang

Coupling constants of $\eta$ and $\eta^{\prime}$ mesons with nucleons have been calculated using the method of QCD sum rules. Starting from vacuum-to-meson correlation function of interpolating fields of two nucleons, its matrix element…

High Energy Physics - Phenomenology · Physics 2019-03-06 Janardan P. Singh , Shesha D. Patel
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