Positrons may get trapped in copper nanoparticles embedded in iron, which has been recently well evidenced experimentally. In this contribution we treat this effect theoretically and present an improved approach to simulations of properties of positrons trapped in copper nanoparticles embedded in the iron bcc matrix.
The presented approach can be used to determine the size of Cu nanoparticles in model Fe-Cu alloys using coincidence Doppler broadening spectroscopy.