Exotic resonances of fully-heavy tetraquarks in a lattice-QCD insipired quark model

Fully-heavy tetraquark states, i.e., $cc\overline{c}\overline{c}$, $bb\overline{b}\overline{b}$, $bb\overline{c}\overline{c}$ ($cc\overline{b}\overline{b}$), $cb\overline{c}\overline{c}$, $cb\overline{b}\overline{b}$, and $cb\overline{c}\overline{b}$, are systematically investigated by means of a nonrelativistic quark model based on lattice-QCD studies the two-body $Q\overline{Q}$ interaction, which exhibits spin-independent Cornell potential along with spin-spin term. The four-body problem is solved using Gaussian expansion method; additionally, so-called complex scaling technique employed so that bound, resonance, scattering states can be treated same footing. Moreover, complete set configurations, including meson-meson, diquark-antidiquark, K-type as well their couplings, considered for spin-parity quantum numbers ${J}^{P(C)}={0}^{+(+)}$, ${1}^{+(\ifmmode\pm\else\textpm\fi{})}$, ${2}^{+(+)}$ in $S$-wave channel. Several narrow resonances, two-meson strong decay widths less than 30 MeV, found all systems studied. Particularly, fully-charm resonances recently reported LHCb Collaboration, at energy range between 6.2 7.2 GeV di-$J/\ensuremath{\psi}$ invariant spectrum, identified our calculation. Focusing fully-bottom masses 18.9 19.6 found. For remaining charm-bottom cases, obtained within region from 9.8 to 16.4 GeV. All these predicted further examined future experiments.