Univ Adelaide, Dept Phys & Math Phys, Adelaide, SA 5005, Australia
; Univ Adelaide, Special Res Ctr Subatom Struct Matter, Adelaide, SA 5005, Australia
; Acad Sinica, Inst High Energy Phys, Beijing 100039, Peoples R China
In the heavy quark limit, the heavy baryons omega(Q)((*)) (omega stands for Sigma, Xi or Omega and Q = b or c) are regarded as composed of a heavy quark and an axial vector, light diquark with good spin and isospin quantum numbers. Based on this diquark picture we establish the Bethe-Salpeter (BS) equation for omega(Q)((*)) in the limit where the heavy quark has infinite mass, m(Q)-->(infinity). It is found that in this limit there are three components in the BS wave function for omega(Q)((*)). Assuming the kernel to consist of a scalar confinement term and a one-gluon-exchange term we derive three coupled integral equations for the three BS scalar functions in the covariant instantaneous approximation. Numerical solutions for the three BS scalar functions are presented, including a discussion of their dependence on the various input parameters. These solutions are applied to calculate the Isgur-Wise functions xi(omega) and zeta(omega) for the weak transitions Omega(b)((*)) --> Omega(c)((*)). Using these we give predictions for the Cabibbo-allowed nonleptonic decay widths and up-down asymmetries for Omega(b)-->Omega(c)((*)) plus a pseudoscalar or vector meson. [S0556-2821(99)07909-6].