相关论文: QCD Sum Rule for $\Lambda$(1405)

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…

We propose a new interpolating field for S$_{11}$(1535) to determine its mass from QCD sum rules. In the nonrelativistic limit, this interpolating field dominantly reduces to two quarks in the s-wave state and one quark in the p-wave state.…

We propose a new QCD sum rule analysis for the Lambda(1405) and the Sigma(1620). Using the I=0 and I=1 multiquark sum rules we predict their masses.

In this work we report on a new QCD sum rule analysis to predict masses of the excited baryon states (e.g. Sigma(1620) and Lambda(1405)) by using multiquark interpolating fields ($(q\bar{q})(qqq)$). For the Sigma(1620) we consider the…

$\Lambda(1405)$ is one of the interesting particles with its unclear structure and distinct properties. It has a light mass compared to its non-strange counterpart, despite the strange quark it carries. This situation puts the investigation…

The QCD sum rule approach is used to analyze the nature of the rencently observed new resonance $X(4350)$, which is assumed to be a diquark-antidiquark state $[cs][\bar{c}\bar{s}]$ with $J^{PC}=1^{-+}$. The interpolating current…

Using the QCD Sum Rule Method, we estimate the mass of the lowest strange hybrid baryon with $IJ^P=0(1/2)^-$. We find the mass is approximately that of the $\Lambda(1405)$, whose nature has been a puzzle for many decades. Possible tests of…

The mass parameter of orbitally excited $\Lambda_c$ baryons is calculated by using QCD sum rule in the framework of heavy quark effective theory. Two kinds of interpolating current for the excited heavy baryons are introduced. It is…

A new analysis is performed in QCD sum rule for the lightest negative parity baryon Lambda (1405). Mixings of three-quark and five-quark Fock components are taken into account. Terms containing up to dimension 12 condensates are computed in…

New relations between QCD Borel sum rules for masses of Sigma^0 and Lambda hyperons are constructed. It is shown that starting from the sum rule for the Sigma^0 hyperon mass it is straightforward to obtain the corresponding sum rule for the…

We use QCD sum rule approach to calculate the masses of the ground-state Lambda_Q and Sigma_Q^(*) baryons. Contributions of the operators up to dimension six are included in operator product expansion. The resulting heavy baryonic masses…

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…

In a diquark-diquark-antiquark picture of pentaquarks, we use two interpolating currents to calculate the mass of the recently measured $\Xi^{--}$ state in the framework of QCD sum rules. We show that, even though yielding similar values…

We use the QCD sum rule approach to calculate the masses of the Lambda_Q and Sigma_Q baryons to the Lambda_{QCD}/m_Q order within the framework of heavy quark effective theory. We compare the direct approach and the covariant approach to…

Using a specific scheme of the QCD sum rules for heavy quarkonium in the leading approximation over the inverse heavy quark mass, one gets the estimate of the difference between the masses of the heavy meson and heavy quark $\bar \Lambda =…

We systematically construct $I(J^P)=0(3^+)$ six-quark local interpolating currents without derivative operators. We discuss the best choice of operator, and select three $\Delta$-$\Delta$ like operators to perform QCD sum rule analyses to…

In this work we study the Theta(1540) in the framework of QCD sum rules based on (ud)^2\bar{s} diquark clustering as suggested by Jaffe and Wilczek. Within errors, the mass of the pentaquark is compatible with the experimentally measured…

We propose a phenomenological QCD sum rule with an explicit diquark field to investigate the essential ingredients inside the hadrons. Introducing the mass (m_\phi) and the condensate (\phi^2) for the diquark field as parameters in the…

The method of QCD sum rules is used to calculate the mass of a hypothetical stable dihyperon H with the quantum numbers of two Lambda hyperons, whose existence was predicted by R.L. Jaffe [Phys. Rev. Lett. 31, 195, 617(E) (1977)] in the…

In this work, the mass and pole residue of $ X(4685) $ state with spin-parity $J^P=1^+$ are computed by the QCD sum rule approaches up to operator dimension seven based on the diquark-antidiquark configuration. For its mass we get $…