Simulated XIFU spectrum based on best fitting model for A576, p = −100 (α = 0.99). The simulated exposure time is 50 ks. The spectrum is fit with a one temperature apec model. In the top panel we show, in red, the simulated spectrum and in black the best fitting model. In the bottom panel we show residuals in the form of a ratio of data to model. Note how the model reproduces adequately lines from Fe XXIV but only partially lines from Fe XXII and XXIII. Interestingly, the combination of improved resolution and larger throughput with respect to XRISM, allows to detect excess emission at the Fe XXIII line at 1.09 keV and to detect an Fe XXI line at 0.97 keV. The spectrum is shown in the observer frame.