Effective attenuation length dependence on photoelectron kinetic energy for Au from 1Â keV to 15Â keV

► The EAL for Au for an electron kinetic energy of 15 keV is 9.5 nm. ► The experimental EALs are well predicted by the formulas developed by Seah and Gilmore, Jablonski and Powell and Jablonski and Tougaard. ► The extremely large EAL values obtained experimentally demonstrates the extremely large probing depth of the HAXPES technique.