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Related papers: Gluon condensate in charmonium sum rules with 3-lo…

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We point out subtleties in the previous sum rule calculations of the $\pi NN$ coupling associated with using either the PV or the PS coupling schemes in modeling the phenomenological side. We propose a sum rule which is independent of the…

Nuclear Theory · Physics 2007-05-23 Hungchong Kim

Using recent values of \alpha_s, the gluon condensates <\alpha_s G^2> and <g^3 f_abcG^3> and the new data on the \psi/\Upsilon-families, we update our determinations of the MS-bar running quark masses m_c,b(m_c,b) from the SVZ-Moments…

High Energy Physics - Phenomenology · Physics 2018-08-07 Stephan Narison , LUPM-CNRS-Montpellier

We re-examine the estimate of $\als$ and of the QCD condensates from $e^+e^-\rar I=1$ hadrons data. We conclude that $e^+e^-$ at low energies gives a value of $\Lambda$ compatible with the one from LEP and from tau inclusive decay. Using a…

High Energy Physics - Phenomenology · Physics 2011-05-05 S. Narison

We estimate the couplings in the Heavy Hadron Chiral Theory (HHCT) lagrangian from the QCD sum rules in an external axial field. We take into account the perturbative correction to the meson correlator in the infinite mass limit. With the…

High Energy Physics - Phenomenology · Physics 2011-09-13 A. G. Grozin , O. I. Yakovlev

We show that at certain values of QCD condensates the nucleon QCD sum rules with "pole+continuum" model for the hadron spectrum obtain an unphysical solution. This provides constrains for the values of condensates to be consistent with…

Nuclear Theory · Physics 2010-04-28 E. G. Drukarev , M. G. Ryskin , V. A. Sadovnikova

Two new QCD sum rules for nucleons in nuclear matter are obtained from a mixed correlator of spin-1/2 and spin-3/2 interpolating fields. These new sum rules, which are insensitive to the poorly known four-quark condensates, provide…

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

We present a new QCD sum rule with high sensitivity to the continuum regions of charm and bottom quark pair production. Combining this sum rule with existing ones yields very stable results for the msbar quark masses, m_c(m_c)$ and m_b…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jens Erler , Mingxing Luo

The low-energy QCD theorems are generalized in the presence of a constant magnetic field H. Two-loop approximation for the vacuum energy density in the framework of the chiral perturbation theory was obtained and the quark and gluon…

High Energy Physics - Phenomenology · Physics 2009-10-31 N. O. Agasian , I. A. Shushpanov

Momentum sum rule can be used as an inequality to estimate the lower and upper bounds of the momentum fractions of quarks and gluons in a model of proton valid in a limited \textit{x} range. We compute such bounds in a self-similarity based…

High Energy Physics - Phenomenology · Physics 2013-06-21 Akbari Jahan , D K Choudhury

Hybrid charmonium with mass ~4 GeV could be produced via a c c.bar color-octet component in b->c c.bar s. These states could be narrow and could have a significant branching ratio to light hadrons, perhaps enhanced by glueballs. Decays to…

High Energy Physics - Phenomenology · Physics 2011-01-25 F. E. Close , I. Dunietz , P. R. Page , S. Veseli , H. Yamamoto

The QCD vacuum condensates in the Operator Product Expansion are extracted from the final ALEPH data on vector and axial-vector spectral functions from $\tau$-decay. Weighted Finite Energy Sum Rules are employed in the framework of both…

High Energy Physics - Phenomenology · Physics 2010-10-27 C. A. Dominguez , K. Schilcher

We use Ward identities of broken scale invariance to infer the amount of scalar glueball--$\bar{q}q$ meson mixing from the ratio of quark and gluon condensates in the QCD vacuum. Assuming dominance by a single scalar state, as suggested by…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Ellis , H. Fujii , D. Kharzeev

We calculate the weak decay form factors of doubly-heavy baryons using three-point QCD sum rules. The Cutkosky rules are used to derive the double dispersion relations. We include perturbative contributions and condensation contributions up…

High Energy Physics - Phenomenology · Physics 2020-07-15 Yu-Ji Shi , Wei Wang , Zhen-Xing Zhao

In the limit of an infinite number of colors, an analytic expression for the quark condensate in $QCD_{1+1}$ is derived as a function of the quark mass and the gauge coupling constant. For zero quark mass, a nonvanishing quark condensate is…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Burkardt

Instanton effects and three-loop perturbative contributions are incorporated into QCD sum-rule analyses of pseudoscalar ($J^{PC}=0^{-+}$) gluonium. Gaussian sum-rules are shown to be superior to Laplace sum-rules in optimized predictions…

High Energy Physics - Phenomenology · Physics 2015-06-25 Ailin Zhang , T. G. Steele

Generalised unitarity techniques are used to calculate the coefficients of box and triangle integral functions of one-loop gluon scattering amplitudes in gauge theories with $N < 4$ supersymmetries. We show that the box coefficients in N=1…

High Energy Physics - Theory · Physics 2008-11-26 Steven J. Bidder , N. E. J. Bjerrum-Bohr , David C. Dunbar , Warren B. Perkins

1. I update my previous comparison of the theoretical value of the muon anomaly with the new measurement and found $\Delta a_\mu\equiv a_\mu^{exp}-a_\mu^{th} = (143\pm 42_{th}\pm 22_{exp})\times 10^{-11}$ which is about 3$\sigma$…

High Energy Physics - Phenomenology · Physics 2024-04-26 Stephan Narison

We consider the assumption that a tachyonic gluon mass imitates short-distance nonperturbative physics of QCD. The phenomenological implications include modifications of the QCD sum rules for correlators of currents with various quantum…

High Energy Physics - Phenomenology · Physics 2009-10-31 K. G. Chetyrkin , Stephan Narison , V. I. Zakharov

The Cornell potential with the best fitted parameters $\alpha_{s}$ and $\kappa$ are modified by adding terms derived from non-perturbative QCD, which are characterized by a series of non-vanishing vacuum condensates of quarks and gluons. In…

High Energy Physics - Phenomenology · Physics 2008-11-26 Y. B. Ding , X. -H. Guo , X. Q. Li , P. N. Shen

We estimate the size of the hadronic matrix elements of CP-violating three-gluon and four-gluon Weinberg operators using sum-rule techniques. In the three-gluon case, we are able to reproduce the expressions given in earlier works, while…

High Energy Physics - Phenomenology · Physics 2020-12-10 Ulrich Haisch , Amando Hala
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