$Q Q \bar Q \bar Q$ states: masses, production, and decays

TL;DR

This paper investigates the existence, production, and decay of heavy quark tetraquark states, providing mass predictions for charm and bottom configurations and encouraging experimental searches.

Contribution

It offers theoretical mass estimates for $Q Q ar Q ar Q$ states and suggests methods for their production and detection, advancing understanding of exotic hadrons.

Findings

Mass of charm tetraquark: 6,192 ± 25 MeV

Mass of bottom tetraquark: 18,826 ± 25 MeV

Proposes experimental search strategies for these states

Abstract

The question of whether there exist bound states of two heavy quarks $Q=(c,b)$ and antiquarks $\bar Q = (\bar c, \bar b)$, distinct from a pair of quark-antiquark mesons, has been debated for more than forty years. We suggest some means of producing and observing $Q_1 Q_2 \bar Q_3 \bar Q_4$ resonant states, concentrating on the $c c \bar c \bar c$ channel which is most easily produced and the $b b \bar b \bar b$ channel which has a better chance of being relatively narrow. We obtain $M_{(cc)(\bar c \bar c)} = 6,192 \pm 25$ MeV and $M_{(bb)(\bar b \bar b)} = 18,826 \pm 25$ MeV, for the charmed and bottom tetraquarks, respectively. Experimental search for these states in the relevant mass region is highly desirable.