Tetraquark
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Study of doubly heavy tetraquarks in lattice QCD Open
We present results of a lattice calculation of tetraquark states with quark\ncontents $q_1q_2\\bar{Q}\\bar{Q}, \\, q_1,q_2 \\subset u,d,s,c$ and $Q \\equiv b,c$\nin both spin zero ($J=0$) and spin one ($J=1$) sectors. These calculations ar…
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Spectroscopy and decays of the fully-heavy tetraquarks Open
\n We discuss the possible existence of the fully-heavy tetraquarks. We calculate the ground-state energy of the $$bb {\\bar{b}} {\\bar{b}}$$ bound state, where b stands for the bottom quark, in a nonrelativistic effective field theory fra…
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A survey of heavy-antiheavy hadronic molecules Open
Many efforts have been made to reveal the nature of the overabundant resonant structures observed by the worldwide experiments in the last two decades. Hadronic molecules attract special attention because many of these seemingly unconventi…
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Evidence for charm-bottom tetraquarks and the mass dependence of heavy-light tetraquark states from lattice QCD Open
We continue our study of heavy-light four-quark states and find evidence from lattice QCD for the existence of a strong-interaction-stable I(JP)=0(1+) udc¯b¯ tetraquark with mass in the range of 15 to 61 MeV below D¯B* threshold. Since thi…
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A theory of X and Z multiquark resonances Open
We introduce the hypothesis that diquarks and antidiquarks in tetraquarks are separated by a potential barrier. We show that this notion can answer satisfactorily long standing questions challenging the diquark-antidiquark model of exotic …
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Searching for beauty-fully bound tetraquarks using lattice nonrelativistic QCD Open
Motivated by multiple phenomenological considerations, we perform the first search for the existence of
\na b¯bbb ¯ tetraquark bound state with a mass below the lowest noninteracting bottomonium-pair threshold
\nusing the first-principles …
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Heavy Tetraquarks in the Relativistic Quark Model Open
We give a review of the calculations of the masses of tetraquarks with two and four heavy quarks in the framework of the relativistic quark model based on the quasipotential approach and QCD. The diquark-antidiquark picture of heavy tetraq…
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Doubly-hidden scalar heavy molecules and tetraquarks states from QCD at NLO Open
Alerted by the recent LHCb discovery of exotic hadrons in the range (6.2 -- 6.9) GeV, we present new results for the doubly-hidden scalar heavy $(\bar QQ) (Q\bar Q)$ charm and beauty molecules using the inverse Laplace transform sum rule (…
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Implications of heavy quark-diquark symmetry for excited doubly heavy baryons and tetraquarks Open
We give heavy quark-diquark symmetry predictions for doubly heavy baryons and\ntetraquarks in light of the recent discovery of the $\\Xi_{cc}^{++}$ by LHCb.\nFor five excited doubly charm baryons that are predicted to lie below the\n$\\Lam…
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Prospects of discovering stable double-heavy tetraquarks at a Tera-Z factory Open
Motivated by a number of theoretical considerations, predicting the deeply bound double-heavy tetraquarks $T^{\{bb\}}_{[\bar u \bar d]}$, $T^{\{bb\}}_{[\bar u \bar s]}$ and $T^{\{bb\}}_{[\bar d \bar s]}$, we explore the potential of their …
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Towards the understanding of fully-heavy tetraquark states from various models Open
We use a color-magnetic interaction model (CMIM), a traditional constituent quark model (CQM) and a multiquark color flux-tube model (MCFTM) to systematically investigate the properties of the states $[Q_1Q_2][\bar{Q}_3\bar{Q}_4]$ ($Q=c,b$…
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Diffusion Monte Carlo calculations of fully-heavy multiquark bound states Open
We use a diffusion Monte Carlo method to solve the many-body Schr\\"odinger\nequation describing fully-heavy tetraquark systems. This approach allows to\nreduce the uncertainty of the numerical calculation at the percent level,\naccounts f…
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Systematics of fully heavy tetraquarks Open
In this work, we systematically study the mass spectrum of the fully heavy\ntetraquark in an extended chromomagnetic model, which includes both color and\nchromomagnetic interactions. Numerical results indicate that the energy level\nis ma…
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Analysis of the Z(4430) as the First Radial Excitation of the Z<sub>c</sub> (3900)* Open
In this article, we take the Z c (3900) and Z(4430) as the ground state and the first radial excited state of the axial-vector tetraquark states with J PC = 1 +− , respectively, and study their masses and pole residues with the QCD sum rul…
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Lattice investigation of exotic tetraquark channels Open
We perform an $n_f=2+1$ lattice study of a number of channels where past claims exist in the literature for the existence of strong-interaction-stable light-heavy tetraquarks. We find no evidence for any such deeply-bound states, beyond th…
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Analysis of the Vector and Axialvector $QQ\bar {Q}\bar {Q}$ Tetraquark States with QCD Sum Rules Open
In this article, we construct the axialvector-diquark-axialvector-antidiquark\ntype currents to study both the vector and axialvector $QQ\\bar{Q}\\bar{Q}$\ntetraquark states with the QCD sum rules, and obtain the masses\n$M_{Y(cc\\bar{c}\\…
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Masses of doubly heavy tetraquarks with error bars Open
In the heavy-quark limit, the two heavy quarks in a doubly heavy baryon or a\ndoubly heavy tetraquark are bound by their color-Coulomb potential into a\ncompact diquark. The doubly heavy hadrons are related by the approximate\nheavy-quark-…
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Doubly bottom strong-interaction stable tetraquarks from lattice QCD Open
We investigate the possibility of $qq^\prime \bar Q \bar Q$ tetraquark bound states using $n_f=2+1$ lattice QCD ensembles with pion masses $\simeq 164$, $299$ and $415$ MeV. Motivated by observations from heavy baryon phenomenology, we con…
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Fully-heavy tetraquark spectra and production at hadron colliders Open
Motivated by the observation of exotic structure around 6900MeV in the\n$J/\\psi$-pair mass spectrum using proton-proton collision data by the LHCb\ncollaboration, we study the spectra of fully-heavy tetraquarks within\nBethe-Salpeter equa…
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First Observation of a Doubly Charged Tetraquark and Its Neutral Partner Open
A combined amplitude analysis is performed for the decays B^{0}→D[over ¯]^{0}D_{s}^{+}π^{-} and B^{+}→D^{-}D_{s}^{+}π^{+}, which are related by isospin symmetry. The analysis is based on data collected by the LHCb detector in proton-proton…
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Hidden-charm and bottom tetra- and pentaquarks with strangeness in the hadro-quarkonium and compact tetraquark models Open
In two recent papers, we used the hadro-quarkonium model to study the properties of hiddencharm and bottom tetraquarks and pentaquarks. Here, we extend the previous results and calculate the masses of heavy-quarkonium-kaon/hyperon systems.…
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Doubly heavy tetraquarks in QCD sum rules Open
In the framework of QCD Sum Rules we investigate the $q q^\prime \bar{Q} \bar{Q}$ tetraquark structure with quantum number $J^P = 1^+$, which are embedded in two types of configurations, the $[8_c]_{q \bar{Q}} \otimes [8_c]_{q^\prime \bar{…
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The light scalar mesons as tetraquarks Open
We present a numerical solution of the four-quark Bethe–Salpeter equation for ground-state scalar tetraquarks with JPC=0++. We find that the four-body equation dynamically generates pseudoscalar-meson poles in the Bethe–Salpeter amplitude.…
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Fully-heavy tetraquarks in a strongly interacting medium Open
We study the properties of fully-heavy tetraquarks at finite temperature and\ntheir production in high-energy nuclear collisions. We obtain the masses and\nwave functions of the exotic hadron states $cc\\bar c\\bar c$ and $bb\\bar b\\bar\n…
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Hidden charm octet tetraquarks from a diquark-antidiquark model Open
Four exotic charmonium-like states, i.e. $X(4140)$, $X(4274)$, $X(4500)$, and $X(4700)$, have been observed very recently by LHCb Collaboration in the decay process $B^+\to J/\psi \phi K^+$ using the 3${\rm fb}^{-1}$ data of $p\bar p$ coll…
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Analysis of the Axialvector Doubly Heavy Tetraquark States with QCD Sum Rules Open
In this article, we construct the axialvector-diquark-scalar-antidiquark type\ncurrents to interpolate the axialvector doubly heavy tetraquark states, and\nstudy them with the QCD sum rules in details by carrying out the operator\nproduct …
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Analysis of the X0(2900) as the scalar tetraquark state via the QCD sum rules Open
In this article, we study the axialvector-diquark–axialvector-antidiquark (AA)-type and scalar-diquark–scalar-antidiquark (SS) type fully open flavor [Formula: see text] tetraquark states with the spin-parity [Formula: see text] via the QC…
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Deciphering the Nature of X(3872) in Heavy Ion Collisions Open
Exploring the nature of exotic multiquark candidates such as the X(3872) plays a pivotal role in understanding quantum chromodynamics (QCD). Despite significant efforts, consensus on their internal structures is still lacking. As a prime e…
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Analysis of the Zc(4200) as axial-vector molecule-like state Open
In this paper, we assume the [Formula: see text] as the color octet–octet type axial-vector molecule-like state, and construct the color octet–octet type axial-vector current to study its mass and width with the QCD sum rules. The numerica…
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Simulating one-dimensional quantum chromodynamics on a quantum computer: Real-time evolutions of tetra- and pentaquarks Open
Quantum chromodynamics (QCD)—the theory of quarks and gluons—has been studied for decades, but it is yet to be fully understood. A recent example is the prediction and experimental discovery of tetraquarks, which opened a new research fiel…