POSSIBLE EXISTENCE OF TOPPED HADRONS

Abstract

We study possibilities of formation of the topped hadrons, the [Formula: see text], [Formula: see text], tqq, ttq and ttt bound systems. We assume that the inverse of binding energy is the parameter of the formation time of the bound system and take the ratio Γtotal/EB as a criterion for the formation of these hadrons, where EB and Γtotal are a binding energy and a total decay width of a topped system respectively. We take into account the binding force caused by the Higgs scalar exchange as well as the one-gluon exchange. It is shown that there is no possibility of forming the single top quark hadrons before the top quark decay. In the standard model, where only one Higgs doublet contributes, among the topped hadrons only toponium [Formula: see text] and the three-top-quark baryon Ωttt with the top quark mass less than 140 GeV and 130 GeV have a possibility of forming the bound states before their decay. In the case of the two-Higgs-doublet model we show that there is a possibility of forming the topped hadrons, toponium, Ξtt and Ωttt for the larger top quark mass if the ratio of vacuum expectation values of two Higgs scalars is large near to the unitarity bound.