Marginalized posterior distributions at 68% C.L. and 95% C.L. in the parameter space of ϵ_s and ϵ_∞ for scalar field modes (see Sect. 5.1.4). We have computed ϵ_s and ϵ_∞ for various quintessence potentials V(φ), with the functional forms of V(φ) labelled on the figure. The field φ is in reduced Planck mass M_P units. The normalization of V(φ) is computed using Ω_m = 0.3. Here Planck indicates Planck TT+lowP.