Caption: Number of sources per log flux that can be detected in a single pointing with Athena/WFI (with and without Filter Wheel Optical Blocking Filter), XMM-Newton/EPICpn (medium filter), and Chandra/ACIS-I. The Athena/WFI curve assumes SPO optics with 15 mirror rows, 2.3 mm rib pitch, and Ir+B4C coating.

Creation date: October 2018.

Credits: A.Rau/WFI Team