Top figure: EPIC MOS 1 (black), MOS 2 (red), and pn (green) spectra of ρ Ophiuchi during the high rate phase (top panel) and χ² terms (bottom panel). The APEC components are plotted with dotted lines. A high temperature of ~3 keV is detected during the rise and the high rate phase. Bottom figure: same plot for HIP 100751. We note the harder spectrum of ρ Ophiuchi compared to HIP 100751. The spectra are accumulated from the same events selected for the light curve (see Fig. 1).