X-ray spectra including primary and secondary peaks, first and second minima, and phase-folded light curves in different energy bands of RBS 1223 combined from 12 pointed XMM-Newton EPIC pn observations. Fitted absorbed blackbody with Gaussian absorption-line models (phabs*bbodyrad*gabs XSPEC) to the spectra and two sinusoids to the phase-folded light curves are also shown (for details, see text and Table 2). Dotted vertical lines indicate the phase intervals used for the extraction and fitting of spectra shown in the left panel.