Table 1. Relaxation times and their relative errors obtained by ESS and QENS.

τ_INPUT/μeV	τ_ESS/μeV	τ_QENS/μeV	Δτ/τ ESS %	Δτ/τ QENS %
5	4,918	5,250	−1,637	4,990
6	6,492	6,102	8,200	1,708
8	8,585	8,522	7,306	6,522
10	10,136	10,404	1,355	4,038
12	11,240	12,874	−6,338	7,284
		<Δτ/τ>/%	4,967	4,908

ESS adopts a model-free approach aimed to extract the abscissa of inflection points, whereas QENS needs an a priori model that here was the same one used as input in the simulations, something that is not possible in real experiments where any model can be proposed a priori. The error on the relative error is 1.2%, so ESS and QENS have the same ability but QENS was given all the advantages, which is not usually realistic in practice.