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Related papers: The possible $\Sigma^0$-$\Lambda$ mixing in QCD su…

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We investigate the $K_1(1270)-K_1(1400)$ mixing caused by the flavor $SU(3)$ symmetry breaking. The mixing angle is expressed by a $K_{1A}\to K_{1B}$ matrix element induced by the operators that breaks flavor $SU(3)$ symmetry. The QCD…

High Energy Physics - Phenomenology · Physics 2023-11-01 Yu-Ji Shi , Jun Zeng , Zhi-Fu Deng

The external-field QCD Sum Rules method is used to evaluate the coupling constant of the light isoscalar-scalar meson (``$\sigma$'' or \epsilon) to the nucleon. The contributions that come from the excited nucleon states and the response of…

Nuclear Theory · Physics 2008-11-26 G. Erkol , Th. A. Rijken , R. G. E. Timmermans

We compute the ratio $\Lambda_L/\Lambda_{\bar{MS}}$ between the scale parameter $\Lambda_L$, associated with a lattice formulation of QCD using the overlap-Dirac operator, and $\Lambda_{\bar{MS}}$ of the $\bar{\rm MS}$ renormalization…

High Energy Physics - Lattice · Physics 2009-10-31 C. Alexandrou , H. Panagopoulos , E. Vicari

In the QCD sum rule approach we predict the $\Lambda$ (1405) mass by choosing the $\pi^0\Sigma^0$ multiquark interpolating field. It is found that the mass is about 1.419 GeV from $\Pi_1 (q^2)$ sum rule which is more reliable than $\Pi_q…

Nuclear Theory · Physics 2009-10-30 Seungho Choe

I present a mini-review of the masses and couplings of the bare (unmixed) light scalar mesons : $\bar qq, (\overline{qq})(qq), (\bar qq)(\bar qq), gg$ from QCD spectral sum rules (QSSR) and low-energy theorems (LET) which we compare with…

High Energy Physics - Phenomenology · Physics 2009-05-06 Stephan Narison

We use QCD spectral sum rules to extract the Sigma_c and Lambda_c magnetic moments. The elctromagnetic field is treated as the external field. We adopt the value of the susceptibility chi=-4.5 GeV^{-2}, which is determined from an overall…

High Energy Physics - Phenomenology · Physics 2009-10-30 Shi-Lin Zhu , Ze-Sen Yang , W-Y. P. Hwang

We demonstrate that the QCD sum rule method can be successfully applied to the calculation of CP-odd electromagnetic observables induced by a vacuum theta--angle. We implement the approach in calculating the electric dipole moment of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Pospelov , A. Ritz

Using the general form of (Sigma_Q) and (Lambda_Q) (Q=b or c) currents, (Sigma_Q-Lambda_Q) transition magnetic moments are calculated in framework of the light cone QCD sum rules method. In this approach nonperturbative effects are…

High Energy Physics - Phenomenology · Physics 2009-11-07 T. M. aliev , A. Ozpineci , M. Savci

Mixing in the D0 system may provide a sensitive probe for new physics beyond the Standard Model (SM) but has so far eluded experimental observation. The SM predictions are typically small (< 10^{-3}) for the mixing parameters x, y which, in…

High Energy Physics - Experiment · Physics 2009-11-10 Monika Grothe

In this article, we extend our previous work to study the $\Sigma$-type heavy baryons $\Sigma_c$ and $\Sigma_b$ in the nuclear matter using the QCD sum rules, and obtain three coupled QCD sum rules for the masses $M_{\Sigma_Q}^*$, vector…

High Energy Physics - Phenomenology · Physics 2012-04-17 Zhi-Gang Wang

The pion-baryon sigma terms and the strange-quark condensates of the octet and the decuplet baryons are calculated by employing the method of quantum chromodynamics (QCD) sum rules. We evaluate the vacuum-to-vacuum transition matrix…

High Energy Physics - Phenomenology · Physics 2010-04-21 G. Erkol , M. Oka , G. Turan

A new QCD calculation of the B parameter of $K^{0}-\bar{K^{0}}$ mixing is presented. It makes use of polynomial kernels in dispersion integrals in order to practically eliminate the contributions of the unknown pseudoscalar strange…

High Energy Physics - Phenomenology · Physics 2018-04-18 N. F. Nasrallah

We use the method of QCD sum rules to investigate a possible hybrid baryon with the quantum numbers of the $\Lambda$. Using a current composed of uds quarks in a color octet and a gluon, a strange hybrid, the $\Lambda_H$ is found about 500…

High Energy Physics - Phenomenology · Physics 2009-11-10 Leonard S. Kisslinger

Based on the analysis of both Borel and Finite-Energy QCD sum rules, the inclusion of finite mesonic widths leads to a dramatic effect on the predictions for the momentum dependence of the rho-omega mixing matrix element. It is shown that…

Nuclear Theory · Physics 2009-10-28 M. J. Iqbal , Xuemin Jin , Derek B. Leinweber

The properties of $\Sigma$-hyperons in pure $\Sigma$ matter are studied with the finite-density quantum chromo-dynamics sum rule (QCDSR) approach. The $\Sigma\Sigma$ nuclear potential $U_\Sigma$ is most likely strongly attractive, it could…

Nuclear Theory · Physics 2008-11-26 P. Li , X. H. Zhong , L. Li , P. Z. Ning

I calculate the QED coupling, alpha, directly in the MS-bar scheme using an unsubtracted dispersion relation for the three light quarks, and perturbative QCD for charm and bottom quarks. Compact analytical expressions are presented, making…

High Energy Physics - Phenomenology · Physics 2010-04-06 Jens Erler

We use QCD sum rules to study the possible existence of a \Theta c(3250) charmed pentaquark. We consider the contributions of condensates up to dimension-10 and work at leading order in \alpha_s. We obtain m(\Theta c) = (3.21 +/- 0.13) GeV,…

High Energy Physics - Phenomenology · Physics 2013-10-30 R. M. Albuquerque , S. H. Lee , M. Nielsen

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

A new method for calculation of the mixing angle between the hadrons within QCD sum rules is proposed. In this method, the mixing is expressed in terms of quark and gluon degrees of freedom. As an application, the detailed calculation of…

High Energy Physics - Phenomenology · Physics 2011-02-01 T. M. Aliev , A. Ozpineci , V. Zamiralov

The consistency of effective models with QCD is investigated through the use of the QCD sum rule. Taking the potential model for the heavy quark system, we apply the method to two phenomenologically successful parameter sets, and obtain the…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Matsuki , K. Yazaki