Comparison of the residual significance (signal-to-noise, S/N) maps in the energy range of 0.2–200 GeV for models without an H II component (top) and with an H II component (middle) of region I. The left panels show the results of Fermi and Fermi+H II models, the middle panels show the results of dust and dust+H II models, and the right panels illustrate the results of gas and gas+H II models. The color scales are from − 5σ to 5σ. The bottom panel show the distribution of significance (bin size is 0.05 σ of each model without or without the HII component, in which each solid line illustrates the Gaussian function fitted to the corresponding distribution and μ and σ represent the mean and the standard deviation of each fit.