Multi-Gaussian fitting of bright emission lines for the galaxies in our sample. Top: 2D spectra, with the y-axis in pixel units. Center: Gaussian fits of [O III]λ5007Å(left) and Hα (right). Bottom: Fit residuals. The flux axis is normalized to the peak emission of each line. Spectra are shown in light blue (labeled “Data”). The blue shadow represents the variance spectrum. The black line models the fit. The dashed lines show the different fitted components. Gray shadows are flagged regions excluded from fits. The yellow line represents the continuum. Insets that zoom in onto the faint line wings are included in the upper-right corner of each plot.