Best-fit equivalent width (EW) of an iron 1s–2p absorption line for the present spectrum taken with the HEG. The lower x-axis corresponds to the blueshift of an Fe xxv line, the upper x-axis to that of an Fe xxvi line. In this plot positive EW corresponds to emission, negative EW to absorption. Filled squares: present HEG data; open circles: the three components reported by Cappi et al. (2009); star: the component discussed by Ponti et al. (2009).