Related papers: Multiquark picture for Sigma(1620)
We consider the $\Theta^+(1540)$ pentaquark in the string model that correctly reproduces the linear Regge trajectories for the case of orbital excitations of light $q\bar q$ mesons and $qqq$ baryons. Assuming (and arguing in favour of) the…
Triply heavy baryons are investigated in the framework of the relativistic quark model based on the quark-diquark picture in the quasipotential approach in QCD. Masses of the ground and excited states of the $\Omega_{ccc}$, $\Omega_{bbb}$,…
In this article, we study the axialvector-diquark-axialvector-antidiquark ($AA$) type and scalar-diquark-scalar-antidiquark ($SS$) type fully open flavor $cs\bar{u}\bar{d}$ tetraquark states with the spin-parity $J^P={0}^+$ via the QCD sum…
Our study focuses on the $\Lambda$-type P-wave bottom baryon states with the spin-parity $J^P=\frac{1}{2}^-$, $\frac{3}{2}^-$. We introduce an explicit P-wave between the two light quarks in the interpolating currents (and the two light…
The spectrum of the $c qq$ baryons contains a few states whose nature is not clearly a three-quark composite and which might have a sizable baryon-meson component. Examples include the $\Sigma_c(2800)$ or the $\Lambda_c(2940)$. Here we…
We have studied the masse spectra for the $cc\bar{b}\bar{b}$/$bb\bar{c}\bar{c}$ tetraquark states with quantum numbers $J^{P}=0^{\pm},1^{\pm}$, and $2^{+}$. We systematically construct the interpolating currents with various spin-parity…
For the heavy baryons $\Xi_c$ and $\Xi_b$ the coupling constants $g_{\Xi_c\Xi_c\pi}$ and $g_{\Xi_b\Xi_b\pi}$ are calculated in the framework of light cone QCD sum rules. The most general form of the interpolating field of $\Xi_Q$ is used in…
We investigate the baryon mass spectrum in quenched lattice QCD with exact chiral symmetry. For 100 gauge configurations generated with Wilson gauge action at $ \beta = 6.1 $ on the $ 20^3 \times 40 $ lattice, we compute (point-to-point)…
We have studied the three quark systems in an Effective Hamiltonian approach in QCD. With only two parameters: the string tension sigma and the strong coupling constant alpha_s we obtain a good description of the ground state light and…
In this article, we extend our previous work to study the $\Sigma$-type heavy baryons $\Sigma_c$ and $\Sigma_b$ in the nuclear matter using the QCD sum rules, and obtain three coupled QCD sum rules for the masses $M_{\Sigma_Q}^*$, vector…
The nuclear density dependencies of the neutron and $\Sigma$ and $\Lambda$ hyperons are important inputs in the determination of the neutron star mass as the appearance of hyperons coming from strong attractions significantly changes the…
In the present work, we construct eight six-quark currents to study the $\Sigma_c\bar{\Sigma}_c$ baryonium and $\Sigma_c\Sigma_c$ dibaryon states via the QCD sum rules. For either $\Sigma_c\bar{\Sigma}_c$ baryonium or $\Sigma_c\Sigma_c$…
We present a systematic study of the masses of light excited $q\bar{q}$ mesons using QCD sum rules at next-to-leading order (NLO). To probe excited states, we construct several interpolating currents with covariant derivatives inserted. The…
The masses of excited heavy mesons are studied with sum rules in the heavy quark effective theory. A set of interpolating currents creating (annihilating) excited heavy mesons with arbitrary spin and parity are proposed and their properties…
In this article, we re-study the heavy baryon states $\Omega_b$, $\Omega_c$, $\Xi'_b$, $\Xi'_c$, $\Sigma_b$ and $\Sigma_c$ with the QCD sum rules, after subtracting the contributions from the corresponding negative parity heavy baryon…
QCD inequalities are derived for the masses of mesons and baryons containing a single heavy quark using the heavy quark effective field theory. A rigorous lower bound is obtained for the $\bar\Lambda$ parameters of the heavy quark effective…
The measured masses of the three charge states of the charmed $\Sigma_c$ baryon are found to be in disagreement with a sum rule based on the quark model, but relying on no detailed assumptions about the form of the interaction. This poses a…
Chiral symmerty is presumed to be a crucial component in the strong interaction and QCD, but its role in spectroscopy, especially for baryons, has not been fully explored. Compounding this, chiral fermions are uncommon in lattice…
We study the $Y(2175)$ using the method of QCD sum rules. There are two independent $ss\bar s\bar s$ interpolating currents with $J^{PC} = 1^{--}$, and we calculate both their diagonal and off-diagonal correlation functions. We obtain two…
In this work we investigate the consequences of the Jaffe and Wilczek diquark model in the framework of QCD sum rules. An analysis of the Theta^+(1540) as (ud)^2\bar{s} state shows that the mass of the pentaquark is compatible with the…