Related papers: Doubly heavy $QQ$ tetraquarks
During the last three years strong experimental evidence from $B$ and charm factories has been accumulating for the existence of exotic hadronic quarkonia, narrow resonances which cannot be made from a quark and an antiquark. Their masses…
A doubly heavy baryon can be regarded as composed of a heavy diquark and a light quark. In this picture, we study the masses of the doubly heavy diquarkes in the Bethe-Salpeter (BS) formalism first, which are then used as one of the inputs…
We look for the existence of stable (by strong interactions) tetraquarks, mesons containing two heavy antiquarks and two light quarks, specifically a $|{\bar b}{\bar b}qq\rangle$ state. This state is viewed as two $|{\bar b}q\rangle $…
In this work, we evaluate the energy spectra of baryons which consist of two heavy and one light quarks in the MIT bag model. The two heavy quarks constitute a heavy scalar or axial vector diquark. Concretely, we calculate the spectra of…
The mass spectra of the excited heavy baryons consisting of two light (u,d,s) and one heavy (c,b) quarks are calculated in the heavy-quark--light-diquark approximation within the constituent quark model. The light quarks, forming the…
We give heavy quark-diquark symmetry predictions for doubly heavy baryons and tetraquarks in light of the recent discovery of the $\Xi_{cc}^{++}$ by LHCb. For five excited doubly charm baryons that are predicted to lie below the $\Lambda_c…
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 $\Omega_{ccc}$, $\Omega_{bbb}$,…
The masses of the ground state heavy baryons consisting of two light (u,d,s) and one heavy (c,b) quarks are calculated in the heavy-quark--light-diquark approximation within the constituent quark model. The light quarks, forming the…
In the limit of heavy quark masses going to infinity, a symmetry is known to emerge in QCD relating properties of hadrons with two heavy quarks to analogous states with one heavy anti-quark. A key question is whether the charm mass is heavy…
Inspired by recent observation of the first doubly charmed tetraquark $T_{cc}$, we apply linear Regge relation and mass scaling to study low-lying mass spectra of the doubly heavy tetraquark in heavy-diquark-light-antidiquark picture. The…
We briefly review the stability of the $QQ\bar q\bar q$-type of tetraquarks with two heavy quarks and two light antiquarks. We present the first comprehensive estimate of the lifetime and leading decay modes of the exotic meson $bb\bar…
The spectrum of doubly heavy baryons, hadrons made up of two heavy quarks and one light quark, is computed through a potential model with relativistic kinematics. The expression for the $Q\bar Q$ potential comes from the AdS/QCD…
The dynamics of two heavy quarks inside the same hadron is probed against the double charm baryon results of SELEX. This can be seen as a part of the mechanism to bind tetraquarks with two heavy quarks and two light antiquarks. In the…
A systematic study of multiquark exotics with one or $N_c-1$ heavy quarks in the large $N_c$ limit is presented. By binding a chiral soliton to a heavy meson, either a normal $N_c$-quark baryon or an exotic $(N_c+2)$-quark baryon is…
We apply the method of QCD sum rules to study the doubly heavy tetraquark states $QQ\bar{q}\bar{n}$ with spin-parity $J^{P}=1^{+}$ and strangeness $S=0, -1$ using careful estimates of the Borel and threshold parameters involved. Masses of…
The existence of bound doubly heavy tetraquark states was confirmed by the recent LHCb discovery of the doubly charmed $T_{cc}$, less than 1 MeV below the meson pair threshold. Others states with two heavy (bottom or charm) quarks could…
For very heavy quarks, the two heavy quarks in a doubly heavy baryon are expected to form a pointlike, heavy diquark in an antitriplet color configuration. In this limit the dynamics of the light degrees of freedom `factorize' from the…
The masses of heavy tetraquarks with hidden charm and bottom are calculated in the framework of the relativistic quark model. The tetraquark is considered as the bound state of a heavy-light diquark and antidiquark. The light quark in a…
In the heavy-quark limit, the two heavy quarks in a doubly heavy baryon or a doubly heavy tetraquark are bound by their color-Coulomb potential into a compact diquark. The doubly heavy hadrons are related by the approximate…
We present new linear relations among the masses of S-wave tetraquarks with either one flavour ($QQ \bar Q \bar Q$) or two ($QQ\bar q \bar q$). Because the relations are sensitive to the hidden-colour, spin, and spatial degrees of freedom,…