How good is the spectral resolution of the XIS?
The spectral resolution depends on the observation modes and the observation date. The user should check it using the calibration source (55Fe) that is attached to the CCD. • How large is the XIS field of view? The XIS field of view is about 17.8 arcmin x 17.8 arcmin. • What is the relation between the PI channel and photon energy? PI = [E(eV)/3.65] You can also find this relation in the RMFs that are part of the Suzaku calibration database. • What is the difference between the 5×5 and the 3×3 data modes? Basically the difference lies in the number of pixels read out around the center of each event; in the 5×5 or 3×3 mode, the data from 25 or 9 pixels are read. Please note that there is no difference in the basic analysis (we use only the 3×3 pixels around the central pixel) and users are free to sum up spectra of both modes. Users should note that, since the FITS structure of event files are different between the 5×5 and the 3×3 modes, 5×5 and 3×3 event files cannot be combined into a
