Gaussian decomposition for Source 1 from the SMC. The top panel shows the H I emission spectrum and its fitting residuals with the shaded area presenting ﹩{\sigma }_{\exp }﹩ noise of the emission spectrum. The bottom panel presents the HI optical depth (absorption spectrum) and its fitting residuals with shaded area presenting σ_τ noise of the absorption spectrum. The total fits for both the emission and absorption spectra are shown in orange, while the individual CNM components are represented in green, and the individual WNM components are shown in gray. Following the “CNM” label, the weighted-mean spin temperature is presented. The “F” value following each “WNM” label quantifies the fraction of WNM in front of CNM, as stated in the text. The three values in each set of square brackets are, respectively, the amplitude, the central velocity, and the FWHM of each fitted Gaussian component. All spectral fits are presented in the Appendix.