Related papers: Diquark and light four-quark states
In this paper, a new type of hybrid state, which consists of two valence quarks and two valence antiquarks together with a valence gluon, the gluonic tetraquark states, are investigated. Twenty-four currents of the the gluonic hidden-charm…
In this article, we study the light-flavor scalar and axial-vector diquark states in the vacuum and in the nuclear matter using the QCD sum rules in an systematic way, and make reasonable predictions for their masses in the vacuum and in…
Hadronic states composed of multi-quark flavors may exist in reality since they are not prohibited by QCD. Compact four quark systems of color singlet are classified as tetraquarks. To understand the properties of these states, more…
We present a numerical solution of the four-quark Bethe-Salpeter equation for ground-state scalar tetraquarks with J^PC = 0^++. We find that the four-body equation dynamically generates pseudoscalar-meson poles in the Bethe-Salpeter…
In this work, we present a systematic calculation of the mass spectrum for tetraquark hybrid states, focusing on the $8_{[c\bar{c}]}\otimes 8_{[G]}\otimes 8_{[c\bar{c}]}$ color configuration, within the framework of QCD sum rules. As an…
We use the QCD sum rules to evaluate the form factors associated with the semileptonic decays of $D_s$ and $D$ mesons into $f_0(980)$. We consider the $f_0(980)$ meson as a quark-antiquark state with a mixture of strange and light…
The low-lying light tetraquark states are investigated in the non-relativistic quark model (NRQM) including the pseudoscalar meson exchange, where two different confinement potential schemes, the Cornell potential and the linear potential,…
We determine the mass of tetraquark bound states from a coupled system of covariant Bethe-Salpeter equations. Similar in spirit to the quark-diquark model of the nucleon, we approximate the full four-body equation for the tetraquark by a…
I review some selected aspects of the phenomenology of multiquark states discovered in high energy experiments. They have four valence quarks (called tetraquarks) and two of them are found to have five valence quarks (called pentaquarks),…
In this study, we use the molecular and diquark-antidiquark tetraquark pictures to investigate magnetic and quadrupole moments of the $B_c$-like ground state tetraquarks with the QCD light-cone sum rules with quantum numbers $J^P = 1^+$. In…
In this work, we construct the color $\bar{\mathbf{3}}\bar{\mathbf{3}}\bar{\mathbf{3}}$ type local five-quark currents with the light quarks $qss$ in the flavor octet, and study the $qssc\bar{c}$ pentaquark states via the QCD sum rules in a…
We discuss possibility of the existence of tetraquark states made of four quarks in the string (flux tube) model. The new particle is composed of a diquark and an anti-diquark which are connected by a color flux. It is shown that the…
In this article, we take into account our previous calculations based on the QCD sum rules, and tentatively assign the $X(4630)$ as the $D_s^*\bar{D}_{s1}-D_{s1}\bar{D}_s^*$ tetraquark molecular state or…
In this article, we construct the axialvector-diquark-scalar-antidiquark type currents to interpolate the axialvector doubly heavy tetraquark states, and study them with the QCD sum rules in details by carrying out the operator product…
Diquark correlations are important in baryons, which can be modeled as quark-diquark bound states. In addition, diquarks could play a role in non-standard hadrons such as tetraquarks and pentaquarks. Here, we obtain properties of these…
States beyond those expected in the simple constituent quark model are now emerging. I focus on the scalar glueball and its mixing with states in the $q\bar{q}$ nonet, and also on correlations in Strong QCD that may form diquarks and seed…
Aiming at self-consistent descriptions of multiquark hadrons (such as tetraquarks, pentaquarks, hexaquarks) by means of QCD sum rules, we note that the totality of contributions to two-point or three-point correlation functions that…
In this article, we construct the scalar-diquark-axialvector-diquark-antiquark type interpolating currents, and study the masses and pole residues of the $J^{P}=\frac{3}{2}^{\pm}$ hidden-charmed pentaquark states with the QCD sum rules. In…
At this point it is still unclear whether pentaquarks exist. While they have be seen in some experiments there are many experiments in which they are not found. On the assumption that pentaquarks exist, several authors have studied the…
Investigating the electromagnetic characteristics of unconventional states may offer new insights into their internal structures. In particular, the magnetic moment attributes may serve as a crucial physical observable for differentiating…