Sensitivity of 1670 GHz east and west limb line profiles to (top) torus central position and (bottom) gas dispersion velocity. Top: model calculations, performed here for a radially infinitely narrow torus located at 2, 3, 4, and 6 Saturn radii (R_S), confirm that the absorbing material is located near 4 R_S, and not e.g. in Saturn’s main rings at  <2 R_S. Bottom: model calculations for several values of molecule dispersion velocity V_rms. Best fits are obtained for V_rms = 2.3 km s^-1 (resp. 2.0 km s^-1) for the east (resp. west) limb spectrum. Dynamically colder models with V_rms = 0.8 km s^-1 or V_rms = 0.5 km s^-1 (typical of plume material ejection conditions) produce too narrow absorptions.