SIXTE simulations of one simulated bridge in between galaxy clusters. Left panel: X-IFU simulated spectrum of the gas bridge and its spectral analysis. Spectral data points with error bars (black crosses) are shown with the best-fit model (blue solid line) and its three components: thermal emission from the gas (magenta), X-ray astrophysical background (green), and particle background (orange). Fit results, with errors, for the four physical quantities of the gas components are also shown. Bottom sub-panel: residuals with respect to the model. Right panel: same as left panel, but zooming-in on the 6–6.4 keV energy range (highlighted in yellow in the left panel) where the most prominent emission lines (blended Fe XXV and Fe XXVI K complexes) are present. In both panels data points have been rebinned for display purposes. The plot scaling for the spectra is logarithmic and linear in the left and right panels, respectively.