Approximate analytical energy formulas for N -body semirelativistic Hamiltonians with one-and two-body interactions are obtained within the framework of the auxiliary field method. We first review the method in the case of nonrelativistic two-body problems. A general procedure is then given for N -body systems and a connection is presented between the method and the generalized virial theorem. The procedure is applied to the case of baryons in the large-N c limit.
The Auxiliary Field MethodThe main purpose of the auxiliary field method (AFM) is to obtain approximate closed-form solutions for eigenequations in quantum mechanics. Let us assume that we want to study the eigenvalues and eigenvectors of this general nonrelativistic HamiltonianWe can consider a new Hamiltonian containing an auxiliary fieldν and an auxiliary potential P(x)The elimination of the auxiliary field by a variational procedure, δνH (ν)H (ν 0 ) = H . The original Hamiltonian is then recovered. The idea of the AFM is to replace the auxiliary fieldν by a real parameter ν [1,2]. In this case,Ṽ (r, ν) is a linear function of P(r ), andH (ν) is solvable for some particular P(r ): r 2 or −1/r for instance (with P(r ) = r , only S-states can be obtained analytically). As mentioned below, the choice of P influences the quality of the approximation. The corresponding eigenvalues E(ν) are given by E(ν) = e(ν) + V (I (ν)) − ν P (I (ν)) ,