May 17 – 20, 2021
online via ZOOM
Europe/Warsaw timezone

Lattice QCD rules out some predictions for deeply-bound light-heavy tetraquarks

May 19, 2021, 6:05 PM
20m
online via ZOOM

online via ZOOM

Speaker

Brian Colquhoun (York University)

Description

Some phenomenological models, already fully constrained by fits to the ordinary meson and baryon spectrum, predict deeply-bound tetraquark states containing one or more heavy quarks. We describe lattice QCD studies of a number of channels where such predictions exist. While not precluding shallow binding, our lattice investigations find no evidence of deep binding in either doubly charmed or bottom-charm channels, allowing us to rule out models that predict deep binding in those channels. On the other hand, a consistent picture has emerged from lattice studies by a number of lattice groups of the existence of deeply-bound, strong-interaction-stable $I=0$, $J^P=1^+$ $ud\bar{b}\bar{b}$ and $I=1/2$, $J^P=1^+$ $\ell s\bar{b}\bar{b}$ tetraquarks, where $\ell=u$ or $d$. In this talk we provide the current status of these calculations, describing recent improvements that provide more robust results and shore up phenomenological expectations.

Primary authors

Brian Colquhoun (York University) Dr Renwick James Hudspith (University of Mainz) Dr Anthony Francis (University of Bern) Dr Randy Lewis (York University) Dr Kim Maltman (York University)

Presentation materials