NEUTRAL EXOTICS IN THE COMPOSITE MODEL — ISOSINGLET WEAK BOSON

Abstract

We investigate properties of the isosinglet partner (WS boson) of the composite weak boson in the dynamical subquark model of the Nambu-Jona-Lasinio (NJL) type. The WS boson is assumed to be made up of the isospin-carrying subquark w, and to be subject to the NJL type dynamics. We derive the following properties of the WS boson. It couples to the quarks and leptons with the equal strength g0 (before mixing), and to the weak bosons only through mixing. We find that the current mixing parameter with photon is proportional to the average of the charges of the subquark w, and inversely proportional to the coupling constant g0. The compositeness conditions almost fix g0 in terms of the weak coupling constant g. We see how the present experimental results restrict the mass and the coupling strength of the diagonalized WS boson (called the X boson). We calculate the decay widths of the X boson and the forward-backward asymmetry in [Formula: see text] scattering.