This proposal is part of our research programme to investigate novel forms of spin and orbital order stabilized by quantum fluctuations and geometric frustration effects. The antiferromagnetic spinel FeSc2S4 where electronically-active Fe2+ ions occupy a diamond lattice has been proposed to realize an unusual spin-orbital liquid ground state with no long-range magnetic or orbital order down to temperatures several orders of magnitude lower than the strength of the inter-site exchange interactions. We have recently observed the full bandwidth of the magnetic excitations and also studied the field dependence of the excitations and observed good agreement with a recent theoretical model proposing strongly-dispersive spin-orbital triplons propagating on a spin-orbital singlet ground state stabilized by the strong spin-orbit coupling at the Fe2+ ions. Here we propose to use D7 with energy analysis and polarization setup to determine the temperature-dependence and polarization of low-energy features in the scattering.