The inter-relation of QCD and spectroscopy is discussed under the headings; the parameters of QCD, QCD sum rules, and QCD and current algebra. (Atomindex citation 12:590468)

This work presents the results of our analysis of the accuracy of the pion form factor derived from the local-duality version of QCD sum rules.

QCD sum rules for processes with small momentum transfers are used to calculate the values of the charge radii of the proton and neutron. The results obtained are in good agreement with the experimental values.

In this article, we perform a detailed study of the mass spectrum of the scalar doubly charmed and doubly bottom tetraquark states using the QCD sum rules.

We present a calculation of the N to {delta} electromagnetic transition amplitudes using the method of QCD sum rules. A complete set of QCD sum rules is derived for the entire family of transitions from the baryon octet to decuplet. They are analyzed in conjunction with the ...

We present a calculation of the N to ? electromagnetic transition amplitudes using the method of QCD sum rules. A complete set of QCD sum rules is derived for the entire family of transitions from the baryon octet to decuplet. They are analyzed in conjunction with the ...

We systematically study the L=1 meson spectrum in the context of QCD sum rules for bilinear quark currents of dimension three. We improve the sum rules by including the alpha /sub s/ corrections correctly and take into account the running of the coupling ...

The magnetic moment of the lambda -hyperon is calculated using the QCD sum rule approach of Ioffe and Smilga. In deriving the sum rules special attention is paid to the strange quark mass dependent terms and to several additional terms not considered in e...

A simple pion's form factor representation with physically reasonable analytical structure is applied to QCD sum rules methods. QCD condensate value are obtained through finite-energy sum rules (FESR) and Shifman-Vainstein-Zakharov sum ...

Two novel methods in extracting the spectral information of hadrons in the QCD sum rule technique. The first one is to combine two sum rules so that the pole dominance is achieved and the resonance information is effectively obtained. This method is applied to the pentaquark ?+ and its quantum ...

The Borel transformation technique of Shifman et al is used to obtain QCD sum-rules for V-A spectral functions. In contrast to the situation in the original Weinberg sum-rules and those of Bernard et al, the problem of saturating the sum-rules by low lying resonances is brought under control. Furthermore, the ...

Several Models (mainly two: Vector Meson Dominance and Quark Models) are presented. Their predictions for the Spectral Functions, and the corresponding Sum Rules are obtained. Comparison with the experimental data and QCD constrains is done.

A review is given to pentaquark mass predictions in quark models and QCD. It is pointed out that no successful quark model prediction is available for low-lying pentaquark states. Some new results of direct application of QCD, QCD sum rules and lattice QCD, are also ...

Hyperon magnetic moments are calculated in a modelless way using the QCD sum rules. The results are in agreement with experiment. (Atomindex citation 15:029754)

The tensor form factors of B into p-wave axial vector meson transition are calculated within light cone QCD sum rules method. The parametrizations of the tensor form factors based on the series expansion are presented.

In the framework of a specific scheme of the QCD sum rules for S-wave of the heavy quarkonium one derives an expression, relating the energetic density of quarkonium states and universal characteristics in the heavy quarkonium physics, such as the differe...

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 the (rho) -...

The technique of QCD sum rules permitting to calculate trajectories of mesonic Regge poles and their couplings is formulated. It utilizes analyticity in momentum transfer t of the moments of the appropriate four current amplitude for arbitrary value of th...

Nucleon-nucleon scattering lengths are calculated using QCD sum rules. The calculation is based on the observation that the coefficient of the second-order pole term of the nucleon correlation function is proportional to the nucleon-nucleon scattering len...

We present QCD perturbative O(?2S) corrections to the Bjorken sum rule for the deep-inelastic neutrino-proton scattering, calculated via two new effective algorithms for evaluating coefficient functions of the Wilson operator expansion.

QCD perturbative corrections to the Bjorken sum rule for the deep inelastic neutrino-proton scattering, calculated via two new effective algorithms for evaluating coefficient functions of the Wilson operator expansion are presented. The calculated correct...

A new formulation of the QCD sum rules at finite temperature (T) is developed. Because of the factorization in the operator product expansion, all the soft dynamics including the effect of finite T in the hadronic phase is taken into account in the therma...

In these lectures, I describe basic techniques of the QCD sum rule approach. The basic concepts of the approach are introduced using a simple model of quantum-mechanical oscillator in 2+1 dimensions. Then I discuss their field-theoretical extension and the construction of the operator product expansion for current correlators in ...

The authors extend QCD sum rule analysis to moderate energy fixed angle Compton scattering. In this kinematic region there is a strong similarity to the sum rule treatment of electromagnetic form factors, although the four-point amplitude requires a modification of the Borel transform. To ...

The Borel transformation technique of Shifman et al is used to obtain QCD sum-rules for V-A spectral functions. In contrast to the situation in the original Weinberg sum-rules and those of Bernard et al, the problem of saturating the sum-rules by low lyin...

Electromagnetic form factors of the transition {pi} + {gamma}{sub virt.} {r_arrow} A{sub 1} are calculated by QCD sum rules technique with the description of the pion in terms of the set of wave functions of increasing twist. Obtained results are compared with standard QCD sum ...

In the light-cone representation, vacuum effects are correctly introduced into the dynamics by the inclusion of induced operators. Recently, some of the induced operators in QCD have been derived. The knowledge of these operators makes it possible to perform calculations of the propertied of QCD resonances using essentially the QCD ...

I use QCD sum rule ideas to construct models for generalized parton distributions. To this end, the perturbative parts of QCD sum rules for the pion and nucleon electromagnetic form factors are interpreted in terms of GPDs and two models are discussed. One of them takes the ...

A comprehensive study is made for the magnetic moments of octet baryons in the method of QCD sum rules. A complete set of QCD sum rules is derived using the external-field method and generalized interpolating fields. For each member, three sum ...

A new technique has recently been developed, in which the Maximum Entropy Method is used to analyze QCD sum rules. This approach has the virtue of being able to directly generate the spectral function of a given operator, without the need of making an assumption about its specific functional form. To investigate whether useful results ...

The electromagnetic form factor of the {pi} meson is calculated in terms of the QCD sum rules for a pion axial-vector current with allowance made for the radiative QCD corrections. The derived dependence of the pion form factor on the square of the transferred momentum Q{sup 2} is in good agreement with the ...

The challenging problem of applicability of the perturbative QCD to exclusive processes is revealed.The basic ingredients both of the asymptotic large Q² analysis and of the QCD sum rule approach are analyzed for the simplest and most well-studied example of the pion electromagnetic form ...

The expansion of QCD sum rules (SR) for the pion wave function (WF) by taking into consideration of ''nonlocal condensates'' =M(z/sup 2/), =M/sub mu / etc. is proposed. It is shown that QCD SR for the moments ...

We discuss those aspects of QCD that nourish the hope of finding quark effects in nuclei. The sum rules method in QCD is examined in conjunction with the Fock space method of Brodsky-Lepage with respect to a phenomenology of the hadrons form factors at al...

Hadronic and nuclear processes are covered, in which all final particles are measured at large invariant masses compared with each other, i.e., large momentum transfer exclusive reactions. Hadronic wave functions in QCD and QCD sum rule constraints on had...

We derive the sum rule for the spectral function of the stress-energy tensor in the bulk (uniform dilatation) channel in a general class of strongly coupled field theories. This class includes theories holographically dual to a theory of gravity coupled to a single scalar field, representing the operator of the scale anomaly. In the limit when the operator ...

We report results on the magnetic moments of octet baryons using the method of QCD sum rules. Three sum rules from three independent tensor structures are derived for each member in the octet (p, n, ?, &+circ;, &-circ;, &-circ;, 0?, and &-circ;) using generalized interpolating ...

Taking the sum rule for the {rho} meson as an example, we study the possibility of explaining the phenomenological enhancement factors for certain terms in the vacuum expectation value of operator product expansion in the QCD sum rule. We take a QCD motivated extended ...

We present a calculation of the N to ? electromagnetic transition amplitudes using the method of QCD sum rules. A complete set of QCD sum rules is derived for the entire family of transitions from the baryon octet to decuplet. They are analyzed in conjunction with the ...

We present a calculation of the N to {delta} electromagnetic transition amplitudes using the method of QCD sum rules. A complete set of QCD sum rules is derived for the entire family of transitions from the baryon octet to decuplet. They are analyzed in conjunction with the ...

The order ?s2 perturbative QCD correction to the Gottfried sum rule is obtained. The result is based on numerical calculation of the order ?s2 contribution to the coefficient function and on the new estimate of the three-loop anomalous dimension term. The correction found is negative and rather small. Therefore it does not affect the ...

We report N* masses in the spin-1/2 and spin-3/2 sectors using the method of QCD Sum Rules. They are based on three independent sets derived from generalized interpolating fields. The predictive ability of each sum rule is examined by a Monte-Carlo based analysis procedure in which all three ...

The vacuum-condensate dependence of nucleon parameters is investigated within QCD sum rules. It is shown that, without allowance for radiative corrections, a solution to the sum-rule equations exists only under stringent constraints on condensate values. There is only an unphysical solution beyond the region ...

We consider the magnetic susceptibility of the quark condensate in nonperturbative QCD by means of the method of Borel sum rules. We show that for a constant external field the value of the magnetic susceptibility is chi(0) = -5.7 +- 0.6 GeV/sup -2/, which agrees well with the sum rules for the ...

sum rules and LGT. We will summarize some of the predictions of these models and techniques, speci be experimentally accessible. 3. Flux-tube model In LGT simulations a roughly cylindrical region of modi#12;ed glue-model states! 4. LGT and QCD Sum Rules LGT and QCD ...

The shape of hadronic distribution amplitudes (DAs) is a critical issue for the perturbative QCD of hard exclusive processes. Recent CLEO data on {gamma}{gamma}{sup *} {r_arrow} {pi}{sup 0} form factor clearly favor a pion DA close to the asymptotic form. The author argues that QCD sum rules for the moments of the ...

The QCD Sum Rules method which links the hadronic degrees of freedom with the underlying QCD parameters, serves as a very useful tool to extract qualitative and quantitative information about hadron properties. The QCD sum rules method has been ...

QCD sum rules are used to compute the first few moments of the mesonic quark momentum. Transverse, longitudinal, and mixed transverse-longitudinal components are examined. The transverse size of the pion is shown to be dictated by the gluon condensate, even though the mass and the longitudinal distribution are dominated by the quark ...

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{sub 0} meson coupling constants are estimated. Our results on these couplings are in good agreement with ...

In this talk the author reports on recent progress in a few areas closely related to the virtual Compton scattering studies. In particular, he discusses the quark-hadron duality estimate of the {gamma}{sup *}p {r_arrow} {Delta}{sup +} transition, QCD sum rule calculation of the {gamma}{gamma}{sup *} {r_arrow} {pi}{sup 0} form factor, ...

We consider the QCD sum rules approach for Delta-isobar magnetic form factor in the infra-red region $0<1GeV^2$. The QCD sum rules in external variable field are used. The obtained formfactor is in agreement with quark model predictions for the Delta-isobar ...

QCD sum rules are used to compute the first few moments of the mesonic quark momentum. Transverse, longitudinal, and mixed transverse-longitudinal components are examined. The transverse size of the pion is shown to be dictated by the gluon condensate, even though the mass and the longitudinal distribution are dominated by the quark ...

The spectrum and the leptonic decay widths of the meson resonances are calculated on the basis of using finite energy sum rules and 1/N-expansion. The obtained results are in good agreement with the experiment, in particular the authors obtain the mass fo...

By means of the QCD sum-rule method we investigate the properties of theleading-twist wave functions of the baryons of the nucleon octet. From theresults of analyzing the sum rules we construct model wave functions. Wecalculate the asymptotic behavior of the magnetic form factors of the hyperons.

We calculate the next-to-leading order perturbative corrections to the SVZ sum rules for the coupling f, the nucleon leading twist wave function at the origin. The results are compared to the established Ioffe sum rules and also to lattice QCD simulations.

We calculate the O(?) and O(?s2) gluon radiative corrections to the QCD sum rule for the first Gegenbauer moment a1K of the kaon light-cone distribution amplitude. The NNLO accuracy is achieved for the perturbative term and quark-condensate contributions to the sum rule. A complete ...

We propose a phenomenological QCD sum rule with an explicit diquark field to investigate the essential ingredients inside the hadrons. By introducing the mass m? and the condensate for the diquark field as parameters in the model, we find that the sum rule works well for ?, ?c, and ...

The q{sub 2} dependence of the {pi}-{eta} mixing amplitude is examined with the use of QCD sum rules. The linear slope of the mixing function {theta}(q{sup 2}) is found to be much smaller than that for {rho}-{omega} mixing. Thus the mixing amplitude is approximately the same in the space-like region as in the time-like one, and one may ...

The external-field QCD sum rules method is used to evaluate the coupling constants of the light isoscalar-scalar meson (�?� or ?) to the ?,?, and ? baryons. It is shown that these coupling constants as calculated from QCD sum rules are consistent with SU(3) flavor ...

The pion-baryon sigma terms and the strange-quark condensates of the octet and the decuplet baryons are calculated by employing the method of QCD sum rules. We evaluate the vacuum-to-vacuum transition matrix elements of two baryon interpolating fields in an external isoscalar-scalar field and use a Monte Carlo-based approach to ...

The use of medium-energy experiments to constrain in-medium four-quark condensates, whose uncertainty is currently the most important problem inhibiting the use of QCD sum rules to study hadrons in nuclear matter, is discussed. A value for a particular linear combination of these condensates is extracted using results of an ...

We derive new QCD sum rules for the axial coupling constants by considering the correlation functions of axial-vector currents in a one-nucleon state. The QCD sum rules tell us that the axial coupling constants are expressed by nucleon matrix elements of quark-gluon ...

The 0++ glueball mass is analyzed in the QCD sum rules. We show that in order to determine the 0++ glueball mass by using the QCD sum rules method, it is necessary to clarify the following three ingredients: (1) to choose the appropriate moment with acceptable parameters ...

We study a QCD sum rule analysis for an exotic tetraquark udss of J{sup P}=0{sup +} and I=1. We construct qqqq currents in a local product form and find that there are five independent currents for this channel. Because of the high dimensional nature of the current, it is not easy to form a good sum ...

In this thesis, QCD Laplace sum-rules for the light quark q�q currents are employed to study the properties of the non-strange I = 0 and I = 1 light quark scalar mesons. This QCD sum-rule analysis allows us to interpret the experimentally observed I = 0 and I = 1 scalar mesons. The H�lder inequality technique ...

We study the pentaquark uudds with J=3/2 and I=1 ({theta}{sup ++}) in the QCD sum rule approach. We derive the QCD sum rules for positive and negative parity states of the pentaquark. The QCD sum rule predicts ...

1. QCD Sum Rules: 20 Years After; 2. QCD Vacuum and Basics of the SVZ Method: 2.1 General ideas; 2.2. Getting started/Playing with toy models; 3. Vacuum Condensates; 4. Rho Meson in QCD; 5. Basic Theoretical Instrument -- Wilson's OPE; 6. Practical Version of OPE; 7. Low Energy Theorems; 8. Are ...

We define parton distribution and decay functions in QCD and prove some of their basic properties. These include renormalization, lightcone expansions and sum-rules. (ERA citation 07:052012)

The spectral function rho V-A (s) is determined from ALEPH and OPAL data on hadronic tau decays using a neural network parametrization trained to retain the full experimental information on errors, their correlations and chiral sum rules: the DMO sum rule, the first and second Weinberg sum ...

The current theoretical status of hybrids and glueballs is reviewed. The predictions of bag, constituent glue, and flux tube models of these states are compared to QCD sum rule and lattice gauge theory calculations. Current ideas about the decays of hybrids and glueballs are also discussed. {copyright} {ital 1998 American Institute of ...

The current theoretical status of hybrids and glueballs is reviewed. The predictions of bag, constituent glue, and flux tube models of these states are compared to QCD sum rule and lattice gauge theory calculations. Current ideas about the decays of hybrids and glueballs are also discussed.

The QCD-based approach to the resonance physics proposed earlier is extended to cover the rho- omega mixing problem. A two-point function relevant to the problem with account of nonperturbative contributions is considered. The sum rules are derived and re...

We present results of a calculation of the electromagnetic pion form factor within the framework of QCD sum rules with nonlocal condensates and using a perturbative spectral density which includes O({alpha}{sub s}) contributions.

Magnetic moments of a proton and a neutron are calculated in the QCD sum rule approach. The substantial role of the external electromagnetic field induced vacuum expectation values, the most important of which is connected with quark condensate magnetic s...

Using the Borel transformed QCD sum rule formalism the masses of L = 1 light quark mesons with isospin I = 1 and I = 0 are calculated. Nonperturbative effects from higher dimensional operators up to dimension d = 6 in the operator product expansion are ta...

The current algebra quark mass estimate made by Leutwyler is found to be consistent with QCD Laplace transform sum rules provided that the quark masses in his relation are interpreted as running masses at a scale of 1.2 GeV.

We compute the diagonal isovector axial-vector as well as induced pseudoscalar form factors of nucleon, ?, and ? baryons by employing the light-cone QCD sum rules to leading order in QCD and including distribution amplitudes up to twist 6. Extrapolating our sum-rules results to low-momentum ...

The method of QCD sum rules provides a powerful technique for the calculation of properties of hadrons in terms of a number of parameters that specify various condensate matrix elements. One may hope that it will be possible to calculate some of the condensate matrix elements using effective Lagrangians. If we concentrate on quark ...

Static and dynamical properties of QCD at finite temperature and density are reviewed. Non-perturbative aspects of the QCD plasma and modification of the hadron properties associated with the chiral transition are discussed on the basis of lattice data, effective theories and QCD sum rules. ...

Static and dynamical properties of QCD at finite temperature and density are reviewed. Non-perturbative aspects of the QCD plasma and the modification of the hadron properties associated with the chiral transition are discussed on the basis of lattice data, effective theories and QCD sum rules. ...

N* masses in the spin-1/2 and spin-3/2 sectors are computed using two non-perturbative methods: lattice QCD and QCD sum rules. States with both positive and negative parity are isolated via parity projection methods. The basic pattern of the mass splittings is consistent with experiments. The mass splitting within ...

N* masses in the spin-1/2 and spin-3/2 sectors are computed using two non-perturbative methods: lattice QCD and QCD sum rules. States with both positive and negative parity are isolated via parity projection methods. The basic pattern of the mass splittings is consistent with experiments. The mass splitting within ...

We extend the QCD sum rule analysis of the form factor F(sub)(gamma*gamma* -> pi^0)(q(sub)1^2, q(sub)2^2) into the region of small virtuality of one of the photons:

theory (APT) to the Bjorken sum rule are presented. We study the third�order QCD correction within perturbative one. The method proposed in [1], called analytic perturbation theory (APT), gives a well of inclusive �decay in [10, 11], where it has been demonstrated that the APT approach can reduce the RS

The induced tensor charge of the nucleon g?, which originates from G-parity violation, is evaluated from QCD sum rules. We find that g?/(gA) with gA being the axial charge is -0.0152 +/- 0.0053 which is proportional to thee u-d quark mass difference. This result is small compared to preliminary analyses of the experiment, but is ...

Using the method of the QCD sum rules, the short distance contribution s-> d(gamma) to the hyperon radiative decays, (Sigma)/sup +/ -> p(gamma) and (gamma)/sup -/ -> (Sigma)/sup -//sub (gamma)/ is analysed. A more reliable estimate of this contribution is...

The radiative decay modes of the newly discovered D{sub sJ}*(2317) and DsJ(2460) states are important to shed light on the quark structure of these mesons. If they are studied within the framework of light cone QCD sum rules, assuming the DsJ mesons as made of a quark-anti-quark pair, one obtains that the radiative decay widths follow ...

Some very unusual features of the hadron structure functions, obtained in generalized QCD sum rules, like the surprisingly strong difference between longitudinally and transversally polarized {rho}-meson structure functions and the strong suppression of the gluon sea in the longitudinally polarized {rho} meson, are discussed.

Within the QCD sum rule approach, we develop a formalism that enables one to calculate the form factors of the heavy-light mesons in the m{sub Q} {yields} {infinity} limit. It is shown that the behavior of the universal Isgur-Wise form factor is determined by the quark propagation function in imaginary time.

In this work, the radiative B{sub c}{yields}D{sub s}*{gamma} decay is investigated in the framework of QCD sum rules. The transition form factors responsible for the decay are calculated. The total branching ratio for this decay is estimated to be in the order of 10{sup -5}, so this decay can be measurable at LHC in the near futu0008.

Using sum rules based on the positivity and the analyticity of the U(1)sub(A) spectral functions, and within the framework of QCD (quantum chromodynamics), we derive an upper bound Msub(p) approximately less than (0.6 approximately 0.75) GeV to the gluon ...

Within the QCD sum rule approach, we develop a formalism that enables one to calculate the form factors of the heavy-light mesons in the m(sub)Q -> infinity limit. It is shown that the behaviour of the universal Isgur-Wise form factor is determined by the quark propagation function in imaginary time.

The pion-nucleon and kaon-nucleon scattering lengths are studied in the QCD sum rule. We show that the leading and next-to-leading order terms of OPE give rise to the Tomozawa-Weinberg and sigma terms, respectively. We also show that in the kaon-nucleon s...

Contributions of fermions to the mass of the scalar glueball 0++ are calculated at two-loop level in the framework of QCD sum rules. It slightly changes the coefficients in the operator product expansion (OPE) and shifts the mass of glueball to 1.72 � 0.07 GeV.

We extend the QCD sum rule analysis of the pion electromagnetic form factor F(sub)pi(Q^2) into the region of moderately large momentum transfers 3GeV^2 < Q^2 < 10 GeV^2, where one should take into account the effects due to nonzero average virtuality of the vacuum quarks and gluons.

We evaluate the pion nucleon and the pion Delta sigma terms by employing the method of quantum chromodynamics (QCD) sum rules. The obtained value of the pion nucleon sigma term is compatible with the larger values already anticipated by the recent calculations. It is also found that the pion Delta sigma term is as large as the pion ...

It is shown that inclusion of the O(G exp 3 ) and O(G exp 4 ) corrections radically changes the theoretical curve for the ratio rsub(n) used to analyse the lowest charmonium states within the QCD sum rule approach. This casts doubt on the soundness of the...

Using a specific scheme of the QCD sum rules for heavy quarkonium int he leading approximation over the inverse heavy quark, one gets the estimate of the difference between the masses of the heavy meson and heavy quark (Lambda)=o.59+-0.02 GeV. 10 refs. (A...

We have calculated the hadronic matrix element that determines the magnitude of B/sup 0/--B-bar /sup 0/ mixing using the method of QCD sum rules. Our result is within good accuracy equal to the value predicted by the hypothesis of vacuum dominance and can therefore serve as a justification for this hypothesis.

The mass spectra of doubly heavy baryons are systematically calculated in the framework of QCD sum rules. With a tentative heavy-diquark-light-quark configuration, the interpolating currents representing the doubly heavy baryons are proposed. Contributions of the operators up to dimension six are included in operator product expansion. ...

The mass spectra of doubly heavy baryons are systematically calculated in the framework of QCD sum rules. With a tentative heavy-diquark light-quark configuration, the interpolating currents representing the doubly heavy baryons are proposed. Contributions of the operators up to dimension six are included in operator product expansion. ...

The masses of nucleon, of isobar delta and of resonance N*(Jsup(P)=3/2sup(-), T=1/2) and the amplitudes of virtual transitions of these states into quark currents are calculated basing on the QCD sum rules. The power corrections of high order in the opera...

The mass spectra of ground-state triply heavy baryons are systematically unscrambled and computed in QCD sum rules. With a tentative (QQ)-(Q) configuration for QQQ, the interpolating currents representing the triply heavy baryons are proposed. Technically, contributions of the operators up to dimension six are included in operator ...

In this paper, we study the {{1}/{2}} + doubly heavy baryon states ?_{{QQ}}^{} and ?_{{QQ}}^{} by subtracting the contributions from the corresponding {{1}/{2}} - doubly heavy baryon states with QCD sum rules, and make reasonable predictions for their masses. Those doubly heavy baryon states may be observed at Tevatron, LHCb and PANDA.

A method for the calculation of the hadronic mixing angles using QCD sum rules is proposed. This method is then applied to predict the mixing angle between the heavy cascade hyperons ?Q and ?Q' where Q = c or Q = b. It is obtained the ?b = 6.4�+/-1.8� and ?c = 5.5�+/-1.8�.

We calculate the form factors and the coupling constant in the ?DD vertex in the framework of QCD sum rules. We evaluate the three point correlation functions of the vertex considering both ? and D mesons off-shell. The form factors obtained are very different but give the same coupling constant: g=6.60�0.31. This number is 50% ...

We present a software package written in Mathematica for standard QCD sum rules calculations. Two examples are given to demonstrate how to use the package. One is for the mass spectrum of octet baryons from two-point correlation functions; the other for the magnetic moments of octet baryons in the external-field method. The free ...

The generalized Baldin sum rule for virtual photon, an unpolarized analog of the generalized Gerasimov-Drell-Hearn sum rule, provides an unique way to investigate the transition between the perturbative QCD and hadronic descriptions of nucleon structure. We report on new measurements in Hall C ...

The ???0 transition magnetic moment is computed in the QCD sum rules approach. Three independent tensor structures are derived in the external-field method using generalized interpolating fields. They are analyzed together with the ? and ?0 mass sum rules using a Monte-Carlo-based analysis, ...

The QCD sum rule technique is employed to investigate pentaquark states with strangeness S = +1 and IJ^? = 012^�,112^�,032^ �,132^�. Throughout the calculation, we emphasize the importance of the establishment of a valid Borel window, which corresponds to a region of the Borel mass, where the operator product expansion (OPE) ...

We present a software package written in Mathematica for standard QCD sum rules calculations. Two examples are given to demonstrate how to use the package. One is for the mass spectrum of octet baryons from two-point correlation functions; the other for the magnetic moments of octet baryons in the external-field method. The software ...

We analyse the extraction of the bound-state form factor from vacuum-to-hadron correlator, which is the basic object for the calculation of hadron form factors in the method of light-cone sum rules in QCD. We study this correlator in quantum mechanics, calculate it exactly, and derive the corresponding OPE. We then apply the standard ...

We study the accuracy of the bound-state parameters obtained with the method of dispersive sum rules, one of the most popular theoretical approaches in nonperturbative QCD and hadron physics. We make use of a quantum-mechanical potential model since it provides the only possibility to probe the reliability and the accuracy of this ...

Mixings of four-quark components in the nonsinglet scalar mesons are studied in the QCD sum rules. We propose a formulation to evaluate the cross correlators of qq and qqqq operators and to define the mixings of different Fock states in the sum rule. It is applied to the nonsinglet scalar ...

We extend the QCD sum rule analysis of the F(sub (gamma))(sup *)(sub (gamma))(sup *) -> (pi)(sup 0) (q(sup 2)(sub 1), q(sup 2)(sub 2)) form factor into the region where one of the photons has small virtuality: q(sup 2)(sub 1) =) 1 GeV...

Charmonia spectral functions at finite temperature are studied using QCD sum rules in combination with the maximum entropy method. This approach enables us to directly obtain the spectral function from the sum rules, without having to introduce any specific assumption about its functional form. ...

An updated investigation of QCD sum rules for the first two moments of {rho}-meson spectral functions, both in vacuum and in-medium, is performed with emphasis on the role of the scale related to spontaneous chiral symmetry breaking in QCD. It is demonstrated that these lowest moments of vector current spectral ...

The authors discuss two types of contributions to hadronic form factors in QCD: hard gluon exchange and soft wave function overlap. Within the QCD sum rule approach, the hard contribution has strong numeric suppression by factor ({alpha}{sub s}/{pi}) {approximately} 0.1 for each exchange. For this reason, the soft ...

The loop level flavor changing neutral current transitions of the ?b-->nl+l- and ?c-->pl+l- are investigated in the light cone QCD sum rules approach. Using the most general form of the interpolating current for ?Q, Q = b or c, the transition form factors are calculated using two sets of input parameters entering the nucleon ...

We derive sum rules involving the spectral density of the stress-energy tensor in N=4 super-Yang-Mills theory and pure Yang-Mills theory. The sum rules come from the hydrodynamic behavior at small momenta and the conformal (in the case of N=4 super-Yang-Mills theory) or asymptotically free (as for the pure ...

We calculate the nucleon parameters in isospin asymmetric nuclear matter using the QCD sum rules. The nucleon self-energies {sigma}{sub v} and {sigma}{sub s}{sup *} are expressed in terms of the in-medium values of QCD condensates. Simple approximate expressions for the self-energies are obtained in terms of these ...

We calculate the nucleon parameters in nuclear matter using the QCD sum rules method. The radiative corrections to only the leading operator product expansion terms are included, with the corrections of the order ?s beyond the logarithmic approximation taken into account. The density dependence of the influence of radiative corrections ...

Due to the very short life time of the ? baryons, a direct measurement on the electromagnetic moments of these systems is almost impossible in the experiment and can only be done indirectly. Although only for the magnetic dipole moments of ? ++ and ? + systems there are some experimental data, the theoretical, phenomenological and lattice calculations could play crucial role. In the present work, ...

Results of electroproduction studies of the higher resonances are reviewed and compared to quark model calculations and to predictions from quark counting rules and QCD sum rules. 30 refs., 18 figs. (ERA citation 14:012151)

The generalized Gerasimov-Drell-Hearn sum rule is known to be very sensitive to QCD radiative and power corrections. We improve the previously developed QCD-inspired model for the Q{sup 2} dependence of the Gerasimov-Drell-Hearn sum rule. We take into account higher order ...

We study the mass of the state Y(2175) of J{sup PC}=1{sup --} in the QCD sum rule. We construct both the diquark-antidiquark currents (ss)(ss) and the meson-meson currents (ss)(ss). We find that there are two independent currents for both cases and derive the relations between them. The operator product expansion convergence of these ...

The QCD light quark mass renormalized at a 1 GeV scale in the M[bar S] scheme is obtained from the numerical results of the lattice QCD simulation with staggered fermions. The primary emphasis is given to the connection between the lattice and continuum parameters. The results are compared with those from the QCD ...

The long-standing problem of the applicability of perturbative QCD to hadronic elastic form factors is discussed. The basic ingredients both of the asymptotic large-Q² treatment and of the QCD sum rule approach are analyzed. The main conclusion is that for accessible energies and momentum ...

The method originally developed for the exact calculations in QED theory is applied for the calculation of NLO effects in QCD Compton processes. QCD corrections to the structure functions and sum rules are obtained. Different interpretations of the NLO effects due to finite quark mass are discussed.

We make use of the temporal gauge to construct a coherent state which is meant to describe the gluon condensate in the QCD vacuum under the assumption that the condensate is in a zero-momentum mode. The state so constructed is a color singlet and will yield finite, nonperturbative vacuum expectation values such as . (This matrix element is found to have a value of about 0.012 ...

We study the {sigma} meson in QCD sum rules using a two-quark interpolating field with derivatives. In the constituent quark model, the {sigma} meson is composed of a quark and an antiquark in the relative p-wave state and is thus expected to have a larger overlap with an interpolating field that measures the derivative of the relative ...

We study pentaquark states with strangeness S=+1 and IJ?=012,112,032,132 within the QCD sum rule technique. In order to obtain reliable results with this method, it is indispensable to establish a valid Borel window, where the operator product expansion (OPE) converges and the presumed ground state pole dominates the ...

We study the ?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 to nucleon spinors to avoid unwanted pole contribution. The SU(3)-flavor symmetry breaking effects have ...

The magnetic moment of the hyperon is calculated using the QCD sum-rule approach of Ioffe and Smilga. It is shown that /sub / has the structure /sub / = (2/3(e/sub u/+e/sub d/+4e/sub s/)(eh-dash-bar/2M/sub /c)(1+delta/sub /), where delta/sub / is small. In deriving the sum rules special attention is paid ...

The external-field quantum chromodynamics (QCD) sum rules method is used to evaluate the coupling constants of the vector mesons ? and ? to the nucleon and the ?,?, and ? baryons. It is shown that these coupling constants as calculated from QCD sum rules are consistent with ...

For this exceptional 25th anniversary of the QCD-Montpellier series of conferences initiated in 85 with the name �Non-perturbative methods�, we take the opportunuity to celebrate the 30?1 years of the discovery of the SVZ (also called ITEP, QCD or QCD spectral) sum rules by M.A. Shifman, ...

We investigate the electromagnetic form factors of the {rho} meson in light cone QCD sum rules. We find that the ratio of the magnetic and charge form factors is larger than 2 at all values of Q{sup 2} (Q{sup 2}{>=}0.5 GeV{sup 2}). The values of the individual form factors at fixed values of Q{sup 2} predicted by the light cone ...

The authors outline how one can approach nonperturbative aspects of the QCD dynamics studying elastic processes at energies accessible at upgraded CEBAF. Their point is that, in the absence of a complete theory of the nonperturbative effects, a possible way out is based on a systematic use of the QCD factorization procedure which separates theoretically ...

We propose a five-dimensional framework for modeling low-energy properties of QCD. In the simplest three parameter model we compute masses, decay rates and couplings of the lightest mesons. The model fits experimental data to within 10%. The framework is a holographic version of the QCD sum rules, motivated by the ...

We propose a five-dimensional framework for modeling low energy properties of QCD. In the simplest three parameter model we compute masses, decay rates and couplings of the lightest mesons. The model fits experimental data to within 5%. The framework is a holographic version of the QCD sum rules, motivated by the ...

QCD sum rules are used to obtain the isovector and isoscalar'' axial vector coupling constants, g{sub A} and g{sub A}{sup S}. We find g{sub A} = 1.26 {plus minus} 0.08, g{sub A}{sup S} = 0.13 {plus minus} 0.08 with sum results for g{sub A}{minus}1 and g{sub A} + g{sub A}{sup S}. These ...

QCD sum rules are used to obtain the isovector and ``isoscalar`` axial vector coupling constants, g{sub A} and g{sub A}{sup S}. We find g{sub A} = 1.26 {plus_minus} 0.08, g{sub A}{sup S} = 0.13 {plus_minus} 0.08 with sum results for g{sub A}{minus}1 and g{sub A} + g{sub A}{sup S}. These sum ...

Within the quantum-chromodynamics (QCD) framework, using the Goldberger-Treiman (GT) relation at the quark level, the charge radii of the heavier pseudoscalar mesons including B/sup +/, B/sup 0/, B/sub s//sup 0/, and B/sub c//sup +/ have been obtained. The lower bounds on the pion charge radius in QCD and extended vector-dominance model (EVDM) are ...

A brief review of data on Q anti Q quark-antiquark states is presented. Masses and leptonic widths of Q anti Q levels on the basis of QCD sum rules are determined. Spin effects in Q anti Q interactions are discussed. Hadronic transitions between quarkoniu...

The amplitudes of virtual transition of a nucleon into quark currents are discussed. The amplitude which determines the proton life time in SUSY grand unified models is found using the QCD sum rules method. (Atomindex citation 15:032105)

The ansatzev for bilocal and three-local quark condensates are built based on computation of some VEV 8 dimension. The new sum rules are obtained, and new constraints for f...

The phenomena of scaling and Bloom-Gilman duality are examined in the context of simple nonrelativistic and relativistic quantum mechanical models. These models are shown to scale and to show the qualitative feature of Bloom-Gilman duality. This suggests that these phenomena do not necessarily require the properties of QCD.

Significant progress has been made in the determination of the light quark masses, using both lattice QCD and sum rule methods, in the last year. The authors discuss the different methods and review the status of current results. Finally, they review the calculation of bottom and charm masses.

QCD sum rules for a polarization operator in external axial and vector fields are used to determine the axial and vector constants of transitions in baryonic decuplet 3/2 sup + . It is shown that axial constant renormalization is caused by interaction bet...

Many new states in the charmonium mass region were recently discovered by the BaBar, Belle and CDF Collaborations. We use the QCD Sum Rule approach to study the possible structure of some of these states.

We clarify the discrepancies of previous results for the masses and decay amplitudes of hermaphrodite mesons obtained from QCD sum rules. We study the case of the strange quark within a light quark expansion formalism. We find that the hermaphrodite masse...

A new approach to the radiative transitions in quarkonium (c, anti c, b anti b, ...) based on the asymptotic freedom of QCD and on the analyticity is proposed. This approach consists in derivation of dispersion sum rules relating the transition amplitudes...

The condition which must be satisfied by the pion wave function is obtained from comparing the perturbative approach and QCD sum rule method for form factor pi sup 0 gamma gamma at different virtualities of photons. (Atomindex citation 17:023854)

We present the gluonic corrections to quark vacuum condensate contributions to various types of current correlation functions. Their relevance to the first Weinberg sum rule is discussed. A new derivation of the relation between the A sub 1 -mass and the ...

The renormalized coupling strength of the {beta}-decay axial vector current is related to {pi}{plus minus} p cross sections through the Adler-Weisberger sum rule, that follows from chiral symmetry. We attempt to understand the Adler-Weisberger sum rule in the 1/N{sub c} expansion in QCD, and in ...

Using the most general form of the interpolating current of the baryons, the strong coupling constants of the light vector mesons with the octet baryons are calculated within the light cone QCD sum rules. The SU(3)f symmetry breaking effects are taken into account in the calculations. It is shown that each of the electric and magnetic ...

We calculate the isoscalar axial-vector coupling constants of the {lambda} hyperon using the method of QCD sum rules. A determination of these coupling constants reveals the individual contributions of the u, d, and the s quarks to the spin content of {lambda}. Our results for the light-quark contributions are in agreement with those ...

We calculate the isoscalar axial-vector coupling constants of the ? hyperon using the method of QCD sum rules. A determination of these coupling constants reveals the individual contributions of the u, d, and the s quarks to the spin content of ?. Our results for the light-quark contributions are in agreement with those from experiment ...

The form factors of the semileptonic Bc-->S(AV)l? (l = ?,?,e) transitions, where S and AV denote the scalar ?c0 and axial vector (?c1,hc) mesons, are calculated within the framework of the three-point QCD sum rules. The results of form factors are used to estimate the total decay widths and branching ratios of these transitions. A ...

We calculate the vector-isovector hadronic current correlation function in the presence of nuclear matter. We find that the rho mass decreases by about 20% at nuclear matter density and the rho width is reduced by about 35%. These results are in general accord with the results of calculations made using QCD sum rules. In our ...

We include effects of nonlocal quark condensates into QCD sum rules (QSR) via the K�ll�n�Lehmann representation for a dressed fermion propagator, in which a negative spectral density function manifests their nonperturbative nature. Applying our formalism to the pion form factor as an example, QSR results are in good agreement ...

We calculate gravitational form factors of vector mesons using a holographic model of QCD. These provide restrictions on the generalized parton distributions of vector mesons, via the sum rules connecting stress tensor form factors to generalized parton distributions. We concentrate on the traceless part of the stress tensor, which ...

We extend the QCD sum rule analysis of the form factor F(sub (gamma)*)(gamma)(sub *(yields)(pi)(sup 0))(q(sub 1)(sup 2),q(sub 2)(sup 2)) into the region of small virtuality of one of the photons, where one should perform more precisely an OPE to factorize...

We study the ?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 to nucleon spinors to avoid unwanted excited states. The SU(3) breaking effects have been accounted in ...

In this paper, we parameterize the vertexes ?^{{ast}}Q ?Q^{{ast}} ? , ?^{{ast}}Q ?Q^{{ast}} K * , ?Q^{{ast}} ?^{{ast}}Q K * and ?Q^{{ast}} ?^{{ast}}Q ? with four tensor structures due to Lorentz invariance, and study the corresponding four strong coupling constants with the light-cone QCD sum rules.

The nonlocal vacuum condensates of QCD describe the distributions of quarks and gluons in the nonperturbative QCD vacuum. Physically, this means that vacuum quarks and gluons have nonzero mean squared momentum, called virtuality. In this paper we study the quark virtuality which is given by the ratio of the local quark-gluon mixed vacuum condensate to the ...

Finite energy sum rules for vector and axial-vector currents are derived in a thermal medium to provide constraints for the spectral behavior of rho and a{sub 1} mesons at nonvanishing temperature and hence to study the tendency toward chiral symmetry restoration. The parity-mixing ansatz for the rho and a{sub 1} spectra, including finite widths, is ...

The difference of vector and axial-vector charged current correlators is analyzed by means of QCD sum rules. The contribution of 10-dimensional 4-quark condensates is calculated and its value is estimated within the framework of the factorization hypothesis. It is compared to the result obtained from an operator fit of Borel ...

We reconsider the Jackiw-Johnson sum rule relating the vector-boson masses (or Goldstone-boson decay constants) to the interactions of the fermions which condense. We show that the counterterm can be simplified to remove all reference to chiral-symmetry breaking, producing a much simpler formula involving no derivatives of the fermion self-energy. This is ...

In this paper, I will emphasize two points on Theoretical Aspects of Lepton-Hadron Scattering: (1) The crucial importance of testing the ``exact`` sum rules as tests of the local current algebra. Discrepancies, if found, between experiment and theory cannot be ``interpreted away`` in terms of more complex parton wave functions for the hadronic ground ...

In this work, we calculate radiative vertex VP? (V=?,?,? and P=?,??) by utilizing ?�? mixing scheme and taking into account the contributions of the three-particle twist-4 distribution amplitudes of the photon in QCD sum rules on light cone. According to experimental data of V?P? and P?V? from PDG, a value of the ?�?? mixing angle, ...

A novel procedure for extracting hadron characteristics from QCD sum rules, based on effective continuum thresholds (necessary for the implementation of quark-hadron duality) which may depend on the involved momenta and on the Borel parameter(s), enables us to quantify the uncertainties induced by the quark-hadron duality approximation ...

Within the QCD sum rule approach the radiative decay J/phi -> etasub(c) gamma is analyzed taking into account both nonperturbative 0(G exp 2 ) and perturbative 0(asub(s)) corrections. Under standard assumptions on the magnitUdes of (GG) and asub(s) the wi...

Modifying the standard approaches to nonperturbative QCD based on Borel-transformed dispersive sum rules by allowing the effective continuum thresholds required for the implementation of quark-hadron duality to depend on the Borel parameters and on any relevant momentum promises to entail higher accuracy and reliable error estimates ...

We extend the earlier suggested QCD-motivated model for the Q{sup 2} dependence of the generalized Gerasimov-Drell-Hearn (GDH) sum rule which assumes the smooth dependence of the structure function g{sub T}, while the sharp dependence is due to the g{sub 2} contribution and is described by the elastic part of the Burkhardt-Cottingham ...

The strong interactions between quarks are believed to be described by Quantum Chromodynamics (QCD), which is a non-abelian SU(3) gauge theory. It is known that QCD undergoes a deconfining phase transition at very high temperatures, that is, at low temperatures QCD is in confined phase, at sufficient high temperatures it is in an ...

The strong interactions between quarks are believed to be described by Quantum Chromodynamics (QCD), which is a non-abelian SU(3) gauge theory. It is known that QCD undergoes a deconfining phase transition at very high temperatures, that is, at low temperatures QCD is in a confined phase, at sufficient high temperatures it is in a ...

The matrix element of the isoscalar axial vector current, bar {u}? ? ?_5u + bar {d}? ? ?_5d , between nucleon states is computed using the external field QCD sum rule method. The external field induced correlator, <0|bar {q}? ? ?_5q |0>, is calculated from the spectrum of the isoscalar axial vector meson states. Since it is ...

Open charm mesons (pseudo-scalar and scalar as well as axial-vector and vector) propagating or resting in nuclear matter display an enhanced sensitivity to the chiral condensate. This offers new prospects for seeking signals of chiral restoration, in particular in pA and \\bar{p}A reactions as envisaged in first-round experiments by the CBM and PANDA collaborations at FAIR. Weinberg-type ...

QCD sum rules for D and B mesons embedded in cold nuclear matter are evaluated. We quantify the mass splitting of D- Dmacr and B- Bmacr mesons as a function of the nuclear matter density; extrapolated to saturation density it is in the order of 60 and 130 MeV, respectively, driven essentially by the condensates , ...

We reexamine the genuine Borel QCD sum rules for the {rho} and {phi} mesons using a simple numerical method to flatten the sum-rule {ital M}{sup 2} dependence in a wide range of {ital M}{sup 2}. Following Das {ital et} {ital al}., the imaginary part of the corresponding polarization operator is written in terms of ...

The moments of the heavy-quark parton distribution functions in a heavy pseudoscalar meson are calculated from QCD sum rules. Expanding these sum rules in the inverse heavy-quark mass we obtain the heavy-mass limits of the moments. Comparison with the finite-mass results reveals that while the ...

The light-cone QCD sum rules approach improved by using the chiral current correlator is systematically reviewed and applied to the calculation of all the heavy-to-light form factors, including all the semileptonic and penguin ones. By choosing suitable chiral currents, the light-cone sum rules ...

The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on fB from two sum rules up to next-to-leading order, i.e. sum rules I and II, which are ...

We calculate the strong coupling constants of light pseudoscalar mesons with heavy baryons within the light cone QCD sum rules method. It is shown that sextet�sextet, sextet�antitriplet and antitriplet�antitriplet transitions are described by one universal invariant function for each class. A comparison of our results on the ...

We study a functional method to extract the V-A condensate of dimension 6 from a comparison of ?-decay data with the asymptotic space-like QCD prediction. Our result is in agreement within errors with that from conventional analyses based on finite energy sum rules.

The vacuum averages of various four-fermion operators are determined on the basis of the QCD sum-rule method. We find that the value of is 3--3.5 times larger than its factorized value, and that is 3--5 times less. A byproduct of our work is a phenomenological determination of the quantity approx. =0.06 GeV/sup 6/.

We summarize three alternative extensions of the quark-valence picture of nucleon strangeness and spin, including (i) gluon spin in QCD, (ii) Bjorken sum rule and QCD, (iii) D-E meson mixing and tadpole leakage. All three approaches suggest that {approx}40% of the nucleon's spin (as well as its momentum) ...

The strong coupling constants of heavy baryons with light vector mesons are calculated in the framework of the light cone QCD sum rules using the most general form of the interpolating currents for the heavy baryons. It is shown that the sextet�sextet, sextet�antitriplet and antitriplet�antitriplet transitions are described by ...

We perform a systematic study of the masses of charmed and bottom baryons in the framework of the QCD sum rule approach. Contributions of the operators up to dimension six are included in operator product expansion. The resulting heavy baryon masses from the calculations are well consistent with the experimental values, and predictions ...

Probing the \\bar{s}s content of the ? and ?' mesons and considering mixing between these states as well as gluonic contributions, the form factors responsible for semileptonic Ds ? (?, ?')l? transitions are calculated via light-cone QCD sum rules. Corresponding branching fractions and their ratio for different mixing angles are also ...

Using a program of perturbative resummation I compute the damping rates for fields at nonzero spatial momentum to leading order in weak coupling in hot QCD. Sum rules for spectral densities are used to simplify the calculations. For massless fields the damping rate has an apparent logarithmic divergence in the infrared limit, which is ...

We provide a covariant description of states of the charmonium and b-quarkonium systems. A very good fit to the spectrum is obtained in both cases in a model whose degrees of freedom are quarks and order parameters of QCD condensates. The current-quark masses used are similar to those suggested in QCD sum-rule studies.

Motivated by recent lattice gauge results that the quarkonium does not dissolve at the critical temperature, we report on recent developments in understanding the properties of charmonium states in the quark gluon plasma using perturbative QCD and QCD sum rule approaches. Using lattice results on the energy density ...

A QCD sum rules method is discussed which enables one to calculate the electron width of vector mesons from the GAMMA-, PSI-, PHI- and rho-families, using their mass spectrum. The results of the calculation agree with available experimental data. In the o...

The QCD sum rule method is formulated for the strangeness +1 pentaquark baryon with isospin I=0 and spin-parity J{sup {pi}}=(3/2){sup {+-}}. The spin-(3/2) states are considered to be narrower than the spin-(1/2) ones, and thus may provide a natural explanation for the experimentally observed narrow width of {theta}{sup +}. In order to ...

The QCD sum rule method is formulated for the strangeness +1 pentaquark baryon with isospin I=0 and spin-parity J?=(3)/(2)�. The spin-(3)/(2) states are considered to be narrower than the spin-(1)/(2) ones, and thus may provide a natural explanation for the experimentally observed narrow width of ?+. In order to obtain reliable ...

QCD sum-rules generally relate the parameters of hadrons to those of quarks and gluons appearing in Quantum Chromodynamics, thus providing a valuable probe into low-energy hadronic phenomena. At low energies, the perturbative approach to QCD breaks down. Nonperturbative effects are considered through the appearance of condensates of ...

The authors investigate a model QCD sum rule for the pion wave function {var_phi}{sub {pi}}(x) based on the non-diagonal correlator whose perturbative spectral density vanishes and {Phi}(x, M{sup 2}), the theoretical side of the sum rule, consists of condensate contributions only. They study ...

Experiments at CEBAF will scan the intermediate-energy region of the QCD dynamics for the nucleon form factors and for Compton Scattering. These experiments will definitely clarify the role of resummed perturbation theory and of quark-hadron duality (QCD sum rules) in this regime. With this perspective in mind, we ...