west region average-stacked observed spectrum (thick gray line) around Hα, compared to (A) average-stacked single Gaussian models (orange line) and individual observed spectra (thin gray lines); (B) Empirical LSF (orange line) and LSF-convolved single Gaussian of various widths (blue lines); (C) composite model (orange line) of a broad Gaussian (green line) added to an LSF-convolved narrow Gaussian of width σ = 0.7 Å.