Related papers: A QCD sum rule analysis of the pentaquark
QCD sum rule is applied to the pentaquark spectroscopy. It is concluded that no positive parity state is seen in low energy region, while there may exist negative parity states at around 1.5 GeV. Choice of interpolating local operators and…
We study the pentaquark $uudd\bar s$ with $J=3/2$ and I=1 ($\Theta^{++}$) 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 that there exists…
In this article, we study the doubly heavy baryon states and pentaquark states with the QCD sum rules by carrying out the operator product expansion up to the vacuum condensates of dimension $7$ and $13$ respectively in a consistent way. In…
The analysis of the sum rules (for two differentchoices of 5-quark currents) indicate that to explain experimental results it is necessary to have some one-particle lower state (and pentaquark is a reliable candidate to this state) while…
We propose a new approach in QCD sum rules applied for exotic hadrons with a number of quarks, exemplifying the pentaquark Theta^{+} (I=0,J=1/2) in the Borel sum rule. Our approach enables reliable extraction of the pentaquark properties…
We present a QCD sum rule analysis for the anti-charmed pentaquark state with and without strangeness. While the sum rules for most of the currents are either non-convergent or dominated by the $DN$ continuum, the one for the non-strange…
The pentaquark width is calculated in QCD sum rules. Result for $\Gamma_{\Theta}$ show, that $\Gamma_{\Theta}$ can vary in the region less than 1$MeV$. The main conclusion is, that if pentaquark is genuine states then sum rules really…
The pentaquark width is calculated in QCD sum rules. The higher dimension operators contribution is accounted. It is shown, that $\Gamma_{\Theta}$ should be very small, less than $1Mev$.
We study $IJ^P=0{3/2}^\pm$ and $1{3/2}^\pm$ pentaquark states with $S=+1$ in the QCD sum rule approach. The QCD sum rule for positive parity states and that for negative parity are independently derived. The sum rule suggests that there…
In this article, we study the $\bar{D}\Sigma_c$, $\bar{D}\Sigma_c^*$, $\bar{D}^{*}\Sigma_c$ and $\bar{D}^{*}\Sigma_c^*$ pentaquark molecular states with the QCD sum rules by carrying out the operator product expansion up to the vacuum…
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…
Exotic penta-quark baryon with strangeness +1, \Theta^+, is studied in the QCD sum rule approach. We derive sum rules for the positive and negative parity baryon states with J=1/2 and I=0. It is found that the standard values of the QCD…
The QCD sum rule technique is employed to investigate pentaquark states with strangeness S = +1 and IJ^P = 0,1/2^\pm, 1,1/2^\pm, 0,3/2^\pm, 1,3/2^\pm. Throughout the calculation, emphasis is laid on the establishment of a valid Borel…
We present an analysis of the newly observed pentaquark $P_c(4312)^+$ to shed light on its quantum numbers. To do that, the QCD sum rule approach is used. The measured mass of this particle is close to $\Sigma_c^{++}\bar{D}^-$ threshold and…
In this work, we explore the ground state mass spectrum of the bottom-charm baryon states in the framework of the QCD sum rules in a comprehensive way. In calculations, we distinguish the contributions of the positive-parity and…
In this article, we construct the scalar-diquark-scalar-diquark-antiquark type current to study the ground state triply charmed pentaquark states with the QCD sum rules. We separate the contributions of the negative-parity and positive…
The negative-parity baryons are studied by a novel approach in the QCD sum rule. It is found that the parity of the ground-state nucleon is determined by the sign of the quark condensate. We predict the mass of negative-parity nucleon.
In the article, we investigate the diquark-diquark-antiquark type fully-heavy pentaquark states with the spin-parity $J^P={\frac{1}{2}}^-$ via the QCD sum rules, and obtain the masses $M_{cccc\bar{c}}=7.93\pm 0.15\,\rm{GeV}$ and…
We study the mass spectra of hidden-charm pentaquarks having spin $J = {1\over2}/{3\over2}/{5\over2}$ and quark contents $uud c \bar c$. We systematically construct all the relevant local hidden-charm pentaquark currents, and select some of…
We present a comprehensive QCD sum rules analysis at next-to-leading order for all types of $J^P=0^{+}$ four-quark states composed of $u$, $d$, and $s$ quarks. The eigenvectors of the renormalization matrix are chosen to be the renormalized…