On the Eigenstates of the Elliptic Calogero-moser Model

It is known that the trigonometric Calogero-Sutherland model is obtained by the trigonometric limit (τ → √ −1∞) of the elliptic CalogeroMoser model, where (1, τ) is a basic period of the elliptic function. We show that for all square-integrable eigenstates and eigenvalues of the Hamiltonian of the Calogero-Sutherland model, if exp(2π √ −1τ) is small enough then there exist square-integrable eigenstates and eigenvalues of the Hamiltonian of the elliptic Calogero-Moser model which converge to the ones of the Calogero-Sutherland model for the 2-particle and the coupling constant l is positive integer cases and the 3-particle and l = 1 case. In other words, we justify the regular perturbation with respect to the parameter exp(2π √ −1τ). With some assumptions, we show analogous results for N-particle and l is positive integer cases.