Improvements in the Monte Carlo code for simulating 4πβ(PC)-γ coincidence system measurements

► Improvements to the Monte Carlo code ESQUEMA are described. ► The experimental extrapolation curve was compared to Monte Carlo simulation. ► Eu-152 was standardized by 4π(PC)β-γ coincidence system and compared to Monte Carlo simulation. ► 4π proportional counter gamma-ray efficiency was calculated by MCNPX and compared with experiment. ► X-ray and positron decay emitters were included in the simulation.