Left columns: NOT net spectra (i.e., spectra after continuum removal) of SN 2014J around Hα (upper panel), [O I] λ6300 (middle panel), and [Ca II] λλ7291, 7324 (lower panel). The thick black histogram lines show the observed spectrum after 10 Å binning. No correction for redshift was made. The blue lines show the modelled line emission, using the model in Lundqvist et al. (2013) for 315 days. The red histogram lines show the modelled flux binned to the same resolution as the binned observed spectrum. The mass of solar-metallicity material in these models are 0.0035 M_⊙, 0.0096 M_⊙, and 0.0060 M_⊙, respectively, and they correspond to the estimated 3σ statistical upper limits of the mass. The modelled spectrum has been redshifted by +241 kms^-1 and reddened according to what is given in Section 1 to match the redshift and extinction of the supernova. A distance of 3.4 Mpc was used. Right columns: quantile-quantile plots of the data in the net spectra. Blue data points are from the distribution of binned fluxes (in 10 Å bins) for 400 Å spectral regions around the modelled lines. The dashed red lines are for the simulated normal distribution. As can be seen, the data samples do not deviate appreciably from a normal distribution, except for the strongest absorption features around the [O I] line, and the strongest emission feature in the [Ca II] spectrum in the lower left panel. No spectral bins were, however, removed from the sample prior to analysis. See text for further details.