Effect of relativistic kinematics on the stability of multiquarks

Jean-Marc Richard (1) , Alfredo Valcarce , Javier Vijande

1 IP2I Lyon - Institut de Physique des 2 Infinis de Lyon

We discuss whether the bound nature of multiquark states in quark models could benefit from relativistic effects on the kinetic energy operator. For mesons and baryons, relativistic corrections to the kinetic energy lead to lower energies, and thus call for a retuning of the parameters of the model. For multiquark states, as well as their respective thresholds, a comparison is made of the results obtained with nonrelativistic and relativistic kinetic energy. It is found that the binding energy is lower in the relativistic case. In particular, QQq¯q¯ tetraquarks with double heavy flavor become stable for a larger ratio of the heavy to light quark masses; the all-heavy tetraquarks QQQ¯Q¯ that are not stable in standard nonrelativistic quark models remain unstable when a relativistic form of kinetic energy is adopted.

Mots clés: Strong Interactions; energy: kinetic; effect: relativistic; correction: relativistic; kinematics: relativistic; multiquark: stability; energy: operator; quark model: nonrelativistic; quark: mass; tetraquark; binding energy; heavy quark; baryon; meson

Domaines: Physique des Hautes Energies - Phénoménologie [hep-ph]

Jean-Marc Richard, Alfredo Valcarce, Javier Vijande. Effect of relativistic kinematics on the stability of multiquarks. Physical Review D, 2021, 103 (5), pp.054020. ⟨10.1103/PhysRevD.103.054020⟩. ⟨hal-03178543⟩