All-heavy tetraquarks

Abstract

In this work, we study the mass spectra of the all-heavy tetraquark systems, i.e., cccc, bbbb, bbcc=ccbb, bccc=ccbc, bcbb=bbbc, and bcbc, within a potential model by including the linear confining potential, Coulomb potential, and spin-spin interactions. It shows that the linear confining potential has important contributions to the masses and is crucial for our understanding of the mass spectra of the all-heavy tetraquark systems. For the all-heavy tetraquarks Q 1 Q 2Q3Q4 , our explicit calculations suggest that no bound states can be formed below the thresholds of any meson pairs ðQ 1Q3 Þ − ðQ 2Q4 Þ or ðQ 1Q4 Þ − ðQ 2Q3 Þ. Thus, we do not expect narrow all-heavy tetraquark states to be existing in experiments.

Triply charmed and bottom baryons in a constituent quark model

“…Recently, with this model we have studied the spectra of the charmonium, bottomonium, B c meson, Ω baryon, and fully-heavy tetraquark states. For there are no measurements of the triply heavy baryons which can be used to constrain the parameters potential model, the model parameters of this work are adopted with the determinations by fitting the charmonium and bottomonium spectra in our previous works [49][50][51]. The masses of the Ω ccc and Ω bbb baryon states predicted in present work reasonably agree with the results obtained with the Lattice QCD calculations [9,15].…”

“…In the above equations, the S i , S and L are the spin operator of the i-th quark, the total spin of the baryon and the total orbital angular momentum of the baryon, respectively; the parameter b, α i j , and α S O denote the strength of confinement potential, strong coupling, and spin-orbit potential, respectively. The seven parameters m c , m b , α cc , α bb , σ cc , σ bb , and b have been determined by fitting the charmonium and bottomonium spectra in our previous works [49][50][51]. In this work, we use the same value of parameter α S O as in Ref.…”

Ω baryon spectrum and their decays in a constituent quark model

“…When all the matrix elements have been worked out, we can solve the generalized matrix eigenvalue problem [39],…”

Double-heavy tetraquarks

“…However, there are still intense debates on the observation of these exotic states. No cccc and bbbb bound states can be formed within effective model calculations [45][46][47][48][49][50] and lattice QCD [51], but possible stable or narrow states in the bbbc and bcbc systems [45,46].…”