The time-averaged XRISM/Resolve spectrum of Mrk 279. The data are plotted in the rest frame and binned using the “optimal” algorithm for fitting and by a further factor of 4.0. The model shown in red is the best-fit extended physical model, including three components for the neutral Fe K emission lines, photoionized emission contributing an H-like Fe XXVI line at 6.97 keV, and photoionized absorption from tentative fast wind components. The solid gray lines indicate the lab energies of the neutral Fe K_α and Fe K_β lines. The dashed gray line indicates the lab energy for the Fe XXVI emission line. The blue and purple lines indicate He-like Fe XXV and H-like Fe XXVI line pairs from potential UFOs at v ≃ 0.22c and v ≃ 0.33c. Please see the text and Table 2.