| Published Articles | |
| Title | Lattice predictions for bound heavy tetraquarks |
| Author(s) | Francis, Anthony (CERN) ; Hudspith, Renwick J (York U., Canada) ; Lewis, Randy (York U., Canada) ; Maltman, Kim (York U., Toronto (main) ; Adelaide U., Sch. Chem. Phys.) |
| Publication | SISSA, 2019 |
| Number of pages | 4 |
| In: | PoS ICHEP2018 (2019) 257 |
| In: | XXXIX International Conference on High Energy Physics, Seoul, Korea, 4 - 11 Jul 2018, pp.257 |
| DOI | 10.22323/1.340.0257 |
| Subject category | Particle Physics - Lattice ; Particle Physics - Phenomenology |
| Abstract | We investigate the possibility of doubly heavy $qq^\prime \bar Q \bar Q^\prime$ tetraquark bound states using $n_f=2+1$ lattice QCD with pion masses $\simeq 164$, $299$ and $415$ MeV. Two types of lattice interpolating operator are chosen, reflecting first diquark-antidiquark and second meson-meson structure. Performing variational analyses using these operators and their mixings, we determine the ground and first excited states from the lattice correlators. Using non-relativistic QCD to simulate the bottom quarks and the Tsukuba formulation of relativistic heavy quarks for charm quarks, we study the $ud\bar b \bar b$, $\ell s\bar b \bar b$ as well as $ud\bar c \bar b$, channels with $\ell=u,d$. In the case of the $ud\bar b \bar b$ and $\ell s\bar b \bar b$ channels unambiguous signals for $J^P=1^+$ tetraquarks are found with binding energies $189(10)$ and $98(7)$ MeV below the corresponding free two-meson thresholds at the physical point. These tetraquarks are therefore not only strong-interaction, but also electromagnetic-interaction stable, and can decay only weakly. So far these are the first exotic hadrons predicted to have this feature. Further evidence for binding is found in the $ud\bar c \bar b$ channel, where the binding energy broadly straddles the electromagnetic stability threshold. We also study the dependence of the tetraquark binding on heavy quark mass by considering the channels $ud\bar b' \bar b'$, $\ell s\bar b' \bar b'$ as well as $ud\bar b' \bar b$, $\ell s\bar b' \bar b$ involving a heavy $b'$ quark with mass between roughly $0.6$ and $6.3$ times the physical $b$ quark mass. The observed mass dependence of these four flavor channels is shown to follow closely a phenomenological form expected on simple physical grounds. |
| Copyright/License | publication: © 2019-2025 The Authors (License: CC-BY-NC-ND-4.0) |
Corresponding record in: Inspire
Notice créée le 2019-11-29, modifiée le 2022-08-10
