It is possible to greatly reduce the effect of pile-up by extracting data from an annulus about the source centre. The optimum inner radius to use depends on the strength of the pile-up but a typical first guess would be 20 arcseconds. The task calculates the encircled energy correction for annuli using the accurate, energy-dependent PSF described in section 5.5. The task epatplot can be used to investigate pile-up issues.
Alternatively for EPIC-pn image mode data a pile-up correction is available within rmfgen.