Electron-impact ionization of argon $3p$ in asymmetric kinematics

Triple differential cross sections are presented for the electron impact ionization of a $3p$ shell of argon, using a model called 3CWZ. Within this model, the projectile as well as the ejected electrons are represented by Coulomb waves with variable charges $Z$($r$) instead of an effective charge; the postcollision interaction (PCI) is also included and treated exactly at all orders of perturbation theory. Our results are compared with recent experiments and other theoretical predictions in a range of several kinematics.