A resolution model for mode multiplets probed with neutron resonance spin-echo spectroscopy

► A resolution model for spin-echo measurements of mode multiplets is tested. ► Phase-sensitive measurements are found to be in agreement with the model predictions. ► A tunable, artificially split dispersion is realized with a double crystal setup. ► Mosaicity-sensitive Larmor diffraction is used to probe the crystal orientation. ► Inelastic measurements show the echo modulation over the probed spin-echo time range.