Example of the Bayesian signal detection scheme applied to a synthetic spectrum of the He i 10 830 Å multiplet obtained with Hazel (Asensio Ramos et al. 2008). The dots display the observations with increasingly higher Gaussian noise. To avoid cluttering, we only show one error bar. The solid red curve is the mean of the predictive distribution, together with the error bars shown as red dotted lines. The blue curves display the contribution of each individual kernel function, and the green curve is the original profile.