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Related papers: Spin Content of Lambda in QCD Sum Rules

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We present a determination of the QCD parameter Lambda in the quenched approximation (n_f=0) and for two flavours (n_f=2) of light dynamical quarks. The calculations are performed on the lattice using O(a) improved Wilson fermions and…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Göckeler , R. Horsley , A. C. Irving , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben

We critically review the validity of heavy-quark spin and flavor symmetries in heavy-light decay constants, form factors and effective couplings obtained within a nonperturbative framework, the ingredients of which are all motivated by…

Nuclear Theory · Physics 2012-02-06 Bruno El-Bennich , Craig D. Roberts , Mikhail A. Ivanov

We obtain a new value for the QCD coupling constant by combining lattice QCD simulations with experimental data for hadron masses. Our lattice analysis is the first to: 1) include vacuum polarization effects from all three light-quark…

High Energy Physics - Lattice · Physics 2009-11-11 Q. Mason , H. D. Trottier , C. T. H. Davies , K. Foley , A. Gray , G. P. Lepage , M. Nobes , J. Shigemitsu

In this paper, we analyze the doubly heavy spin-3/2--spin-1/2 baryons and light meson vertices within the method of light-cone QCD sum rules. These vertices are parametrized in terms of one (three) coupling constant(s) for the pseudoscalar…

High Energy Physics - Phenomenology · Physics 2021-04-07 T. M. Aliev , K. Şimşek

New QCD sum rules for the nucleon axial-vector current coupling constants are derived. One set is derived from a generalized correlator of spin-1/2 interpolating fields, and the other with a mixed correlator of spin-1/2 and spin-3/2 fields.…

Nuclear Theory · Physics 2007-05-23 Frank X. Lee , Derek B. Leinweber , Xuemin Jin

Coupling constants of the pseudoscalar mesons to the octet baryons are computed in the QCD sum rule approach. The pi-NN, eta-NN, pi-XiXi, eta-XiXi, pi-SigmaSigma, eta-SigmaSigma as well as pi-Lambda-Sigma couplings are studied. Determining…

High Energy Physics - Phenomenology · Physics 2009-11-07 Takumi Doi , Hungchong Kim , Yoshihiko Kondo , Makoto Oka

Isospin symmetry breaking in the quark condensates, $< \bar dd> \not= < \bar uu>$, is a fundamental parameter in both the QCD sum rule studies and the chiral perturbation theory. In this article, we apply the QCD sum rule method to treat…

High Energy Physics - Phenomenology · Physics 2007-05-23 W-Y. P. Hwang , Kwei-Chou Yang

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

The question of pseudovector versus pseudoscalar coupling schemes for the kaon-hyperon-nucleon interaction is re-examined for the reaction $\gamma p\to K^+ \Lambda$ in several isobaric models. These models typically include Born terms,…

Nuclear Theory · Physics 2009-11-06 S. S. Hsiao , D. H. Lu , Shin Nan Yang

Light-cone QCD sum rules are employed to compute the strong coupling constants: g_{B^* B^* pi}, g_{B_1 B_0 pi} and g_{B_1 B^* pi}, where (B,B^*) and (B_0,B_1) are negative and positive parity (0^-,1^-) and (0^+,1^+) \bar qQ doublets. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Colangelo , F. De Fazio

We study the strong interactions among the heavy bottom spin--1/2 $\Sigma_b$ baryon, nucleon and $B$ meson as well as the heavy charmed spin--1/2 $\Sigma_c$ baryon, nucleon and $D$ meson in the context of QCD sum rules. We calculate the…

High Energy Physics - Phenomenology · Physics 2015-09-29 K. Azizi , Y. Sarac , H. Sundu

We study the $\eta$NN coupling constant using the method of QCD sum rules starting from the vacuum-to-eta correlation function of the interpolating fields of two nucleons. The matrix element of this correlation has been taken with respect…

High Energy Physics - Phenomenology · Physics 2011-03-15 Janardan P. Singh , Frank X. Lee , Lai Wang

Taking into account the contributions of the quark-quark, quark-gluon, and gluon-gluon condensate corrections, the strong form factors and coupling constants of $D^*_{s0}D^*_0K^*$, $D_sDK^*$, $D^*_sD^*K^*$, $D_{s1}D_1K^*$, $D_sD^*K^*$, and…

High Energy Physics - Phenomenology · Physics 2015-09-08 R. Khosravi , M. Janbazi

We present a compact review of the status of QCD spectral sum rules until 2022. We emphasize the recent progresses for determining the QCD input parameters ($\alpha_s$, running quark masses, quark and gluon condensates) where their…

High Energy Physics - Phenomenology · Physics 2023-08-08 Stephan Narison

We estimate the strong coupling constants of charmed and bottom mesons $ D_{(s)}^* $, $ D_{(s)1} $, $ B_{(s)}^* $, and $ B_{(s)1} $ with light vector mesons $ \rho $, $ \omega $, $ K^* $, and $ \phi $ within the framework of light-cone QCD…

High Energy Physics - Phenomenology · Physics 2021-11-10 T. M. Aliev , K. Şimşek

We present our calculation of the isospin-violating part of the hadronic vacuum polarisation (HVP) contribution to muon $(g-2)$ in lattice QCD at the $SU(3)_{\mathrm{f}}$ symmetric point. The computation of the contributing fully connected…

High Energy Physics - Lattice · Physics 2025-01-08 Dominik Erb , Antoine Gerardin , Harvey B. Meyer , Julian Parrino , Vladimir Pascalutsa , Volodymyr Biloshytskyi

Scalar form factor of the nucleon is calculated in the framework of light cone QCD sum rules, using the most general form of the baryon current. Using the result on scalar form factor of the nucleon, the nucleon-scalar "sigma" and "a_0"…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. M. Aliev , M. Savci

Within the collective coordinate approach to chiral soliton models we suggest that breaking of SU(3) flavor symmetry mainly resides in the baryon wave-functions while the charge operators have no (or only small) symmetry breaking…

High Energy Physics - Phenomenology · Physics 2007-05-23 H. Weigel

A previously introduced relativistic energy density functional, successfully applied to ordinary nuclei, is extended to hypernuclei. The density-dependent mean field and the spin-orbit potential are consistently calculated for a $\Lambda$…

Nuclear Theory · Physics 2008-11-26 P. Finelli , N. Kaiser , D. Vretenar , W. Weise

The electromagnetic coupling constant, $\alpha$, is one of the fundamental parameters of the Standard Model (SM). Its value at the Z boson mass, $\alpha(M_Z)$, is of particular interest as it enters electroweak precision tests. When running…

High Energy Physics - Lattice · Physics 2024-01-09 Sophie Mutzel