Comparison between the observed helium glitch δν_o (solid line) and the one resulting from the best fit model δν_m (dot-dashed line) for l = 0. We also display the observed glitch as a function of the frequencies (errorbars) as well as the best model glitch associated with the theoretical frequencies (diamond). The observed frequencies have been corrected for surface effects using Sonoi et al. (2015)’s prescription.