High precision photoassociation spectroscopy is performed in ultracold cesium gas, with detunings as large as 51 cm-1 below the Cs(6S(1/2))+Cs(6P(3/2)) asymptote. Trap-loss fluorescence detection is used for detecting the photoassociation to excited state ultracold molecules. Long vibrational progressions are assigned to electronic states of 0(g)(-), 0(u)(+), and 1(g) symmetry. The spectral data are fitted to a LeRoy-Bernstein equation, in order to obtain the effective coefficients of the leading long-range interaction term (C-3/R-3) and the relative vibrational quantum numbers measured down from dissociation. Additionally we present evidence for perturbations between the 0(g)(-) state and the dark 2(u) state. (C) 2004 American Institute of Physics.