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In addition to being sensitive to spot asymmetries (e.g. Section 5.1), image slice profiles are sensitive to pileup when plotted as a function of event grade. In Figure 16, the profile in the Y-direction for all event grades (solid line) is superposed on the profile for standard ASCA grades G02346 (dashed line) for the four images in Figure 13, Figure 14, Figure 15, and Table 3. As the degree of pileup increases, the central surface brightness decreases (c.f. Figure 13, Figure 14), but the effect is more dramatic when including only G02346 event grades. The pileup sensitivity of this grade set is set primarily by migration of grade 0 (single pixel) events into the excluded grade 7. This effect may provide a useful means for diagnosing pileup when the true count rate is unknown. A discussion of this can be found at http://asc.harvard.edu/cal/Links/Acis/acis/Cal_prods/pileup/pileup.html