COVARIANT EQUATIONS FOR THE 3-BODY BOUND-STATE

The covariant spectator (or Gross) equations for the bound state of th ree identical spin-1/2 particles, in which two of the three interactin g particles are always on shell, are developed and reduced to a form s uitable for numerical solution. The equations are first written in ope rator form and compared to the Bethe-Salpeter equation, then expanded into plane wave momentum states, and finally expanded into partial wav es using the three-body helicity formalism first introduced by Wick. I n order to solve the equations, the two-body scattering amplitudes mus t be boosted from the overall three-body rest frame to their individua l two-body rest frames, and all effects which arise from these boosts, including the Wigner rotations and rho-spin decomposition of the off- shell particle, are treated exactly. In their final form, the equation s reduce to a coupled set of Faddeev-like double integral equations wi th additional channels arising from the negative rho-spin states of th e off-shell particle.