The RMF of the Epic detectors varies depending on the event grades used to create the spectrum. Different RMFs may be created by the task for single (pattern 0), double (patterns 1–4), triple (patterns 5–8), quadruple (patterns 9-12), single plus double and single plus double plus triple plus quadruple events. The pattern information is read from the datasubspace stored in the spectrum header. The current standard practise is to use singles, doubles or singles plus doubles for Epic-PN and singles or singles plus double plus triple plus quadruple for Epic-MOS but see XMM-SOC-PS-TN-0043 for more details.
