scholarly journals Erratum: Operator product expansion sum rules for heavy flavor transitions and the determination of|Vcb|

1995 ◽  
Vol 52 (5) ◽  
pp. 3149-3149 ◽  
Author(s):  
M. Shifman ◽  
N. G. Uraltsev ◽  
A. Vainshtein
Keyword(s):  
Operator Product Expansion ◽  
Sum Rules ◽  
Operator Product ◽  
Heavy Flavor

scholarly journals Analysis of the D̄Σc, D̄Σc∗, D̄∗Σc and D̄∗Σc∗ pentaquark molecular states with QCD sum rules

2019 ◽  
Vol 34 (19) ◽  
pp. 1950097 ◽  
Author(s):  
Zhi-Gang Wang
Keyword(s):  
Operator Product Expansion ◽  
Sum Rules ◽  
Molecular State ◽  
Operator Product ◽  
Qcd Sum Rules ◽  
Dimension Formula ◽  
Vacuum Condensates

In this paper, we study the [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] pentaquark molecular states with the QCD sum rules by carrying out the operator product expansion up to the vacuum condensates of dimension [Formula: see text] in a consistent way. The present calculations support assigning the [Formula: see text] to be the [Formula: see text] pentaquark molecular state with [Formula: see text], assigning the [Formula: see text] to be the [Formula: see text] pentaquark molecular state with [Formula: see text], assigning the [Formula: see text] to be the [Formula: see text] pentaquark molecular state with [Formula: see text] or the [Formula: see text] pentaquark molecular state with [Formula: see text]. Special attention is paid to the operator product expansion.

scholarly journals SCALAR NONETS IN POLE-DOMINATED QCD SUM RULES

2008 ◽  
Vol 23 (27n30) ◽  
pp. 2230-2233
Author(s):  
TORU KOJO ◽  
DAISUKE JIDO
Keyword(s):  
Operator Product Expansion ◽  
Quark Mass ◽  
Sum Rules ◽  
Operator Product ◽  
Qcd Sum Rules ◽  
Current Quark Mass ◽  
Pole Dominance ◽  
Light Scalar ◽  
Current Quark

The light scalar nonets are studied using the QCD sum rules for the tetraquark operators. The operator product expansion for the correlators is calculated up to dimension 12 and this enables us to perform analyses retaining sufficient pole-dominance. To classify the light scalar nonets, we investigate the dependence on current quark mass and flavor dynamics. Especially, to examine the latter, we study separately SU(3) singlet and octet states, and show that the number of annihilation diagrams is largely responsible for their differences, which is also the case even after the inclusion of the finite quark mass. Our results support the tetraquark picture for isosinglets, while that for octets is not conclusive yet.

scholarly journals Operator Product Expansion, Heavy Quarks, QCD Duality and Its Violations

1997 ◽  
Vol 12 (11) ◽  
pp. 2075-2133 ◽  
Author(s):  
B. Chibisov ◽  
R. D. Dikeman ◽  
M. Shifman ◽  
N. G. Uraltsev
Keyword(s):  
Operator Product Expansion ◽  
Background Field ◽  
Decay Rates ◽  
Operator Product ◽  
Theoretical Treatment ◽  
Heavy Flavor ◽  
Wide Range ◽  
Euclidean Domain ◽  
Inclusive Processes ◽  
Hadron Duality

The quark(gluon)–hadron duality constitutes a basis for the theoretical treatment of a wide range of inclusive processes — from hadronic τ decays and Re+e- to semileptonic and nonleptonic decay rates of heavy flavor hadrons. A theoretical analysis of these processes is carried out by using the operator product expansion in the Euclidean domain, with subsequent analytic continuation to the Minkowski domain. We formulate the notion of the quark(gluon)–hadron duality in quantitative terms, then classify various contributions leading to violations of duality. A prominent role in the violations of duality seems to belong to the so-called exponential terms which, conceptually, may represent the (truncated) tail of the power series. A qualitative model, relying on an instanton background field, is developed, allowing one to get an estimate of the exponential terms. We then discuss a number of applications, mostly from heavy quark physics.

scholarly journals The case for duality violations in the analysis of hadronic τ decays

2016 ◽  
Vol 31 (30) ◽  
pp. 1630031 ◽  
Author(s):  
Santiago Peris ◽  
Diogo Boito ◽  
Maarten Golterman ◽  
Kim Maltman
Keyword(s):  
Operator Product Expansion ◽  
Systematic Errors ◽  
Operator Product ◽  
Higher Dimension ◽  
Convergent Expansion ◽  
Theoretical Evidence ◽  
Made In

In this review, we discuss why, in the determination of [Formula: see text] from hadronic [Formula: see text] decays, two important assumptions made in most of previous analyses, namely the neglect of higher-dimension condensates and of duality violations (DVs), have introduced uncontrolled systematic errors into this determination. Although the use of pinched weights is usually offered as a justification of these assumptions, we explain why it is not possible to simultaneously suppress these two contributions; particularly since the Operator Product Expansion (OPE) is expected to be an asymptotic, rather than a convergent expansion. There is not only experimental and theoretical evidence for DVs but they also affect the extraction of [Formula: see text].

scholarly journals Analysis of the X(3842) as a D-wave charmonium meson

2019 ◽  
Vol 34 (26) ◽  
pp. 1950151
Author(s):  
Guo-Liang Yu ◽  
Zhi-Gang Wang
Keyword(s):  
Experimental Data ◽  
Operator Product Expansion ◽  
Mass Formula ◽  
Decay Constant ◽  
Sum Rules ◽  
Lhcb Collaboration ◽  
Operator Product ◽  
Strong Decay ◽  
State Formula ◽  
Vacuum Condensates

In this paper, we assign the newly reported state [Formula: see text] to be a [Formula: see text]-wave [Formula: see text] meson, and study its mass and decay constant with QCD sum rules by considering the contributions of vacuum condensates up to dimension-6 in the operator product expansion. The predicted mass [Formula: see text] GeV is in agreement with the experimental data [Formula: see text] MeV from the LHCb collaboration. This result supports assigning [Formula: see text] as the [Formula: see text] charmonium meson. In this case, its predicted strong decay width with the [Formula: see text] decay model is compatible with the experimental data.

scholarly journals Isgur–Wise functions, Bjorken–Uraltsev sum rules and their Lorentz group interpretation

2015 ◽  
Vol 30 (10) ◽  
pp. 1543008
Author(s):  
L. Oliver ◽  
J.-C. Raynal
Keyword(s):  
Lorentz Group ◽  
Operator Product Expansion ◽  
Positive Measure ◽  
Sum Rules ◽  
Integral Formula ◽  
Operator Product ◽  
Lorentz Transformations ◽  
Sum Rule ◽  
Heavy Quark Limit ◽  
Higher Derivatives

In the heavy quark limit of QCD, using the Operator Product Expansion and the non-forward amplitude, as proposed by Nikolai Uraltsev, we formulate sum rules that generalize Bjorken and Uraltsev sum rules. We recover the Uraltsev lower bound for the slope of the Isgur–Wise (IW) function, that we generalize to higher derivatives. We show that these results have a clear interpretation in terms of the Lorentz group, since the IW function is given by an overlap between the initial and final light clouds, related by Lorentz transformations. Both the Lorentz group and the Sum Rules approaches are equivalent. Moreover, we formulate an integral representation of the IW function with a positive measure. Inverting this integral formula, we obtain the measure in terms of the IW function, allowing one to formulate criteria to decide if a given ansatz for the IW function is compatible or not with the sum rule constraints. We compare these theoretical constraints to some forms proposed in the literature.

scholarly journals Hidden-Beauty Broad Resonance Yb(10890) in Thermal QCD

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
J. Y. Süngü ◽  
A. Türkan ◽  
H. Dağ ◽  
E. Veli Veliev
Keyword(s):  
Critical Temperature ◽  
Finite Temperature ◽  
Operator Product Expansion ◽  
Sum Rules ◽  
Operator Product ◽  
Broad Resonance ◽  
Qcd Sum Rules ◽  
Pole Residue

In this work, the mass and pole residue of resonance Yb is studied by using QCD sum rules approach at finite temperature. Resonance Yb is described by a diquark-antidiquark tetraquark current, and contributions to operator product expansion are calculated by including QCD condensates up to dimension six. Temperature dependencies of the mass mYb and the pole residue λYb are investigated. It is seen that near a critical temperature (Tc≃190  MeV), the values of mYb and λYb decrease to 87% and to 44% of their values at vacuum.

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