Start-to-end Simulations of the Self-Modulation Experiment at PITZ

The PWFA experiment at the Photo Injector Test facility at DESY, Zeuthen site (PITZ), was launched to experimentally demonstrate and study a promising phenomenon for future plasma-based accelerators and one of the major aspects of the AWAKE experiment -- the self-modulation of long particle beams in plasma. First time-resolved measurements of the self-modulation instability (SMI) of a long electron beam in plasma took place at PITZ in 2016; however the due to technical shortcomings the plasma density during the experiment was about an order of magnitude lower than expected.This contribution describes start-to-end beam dynamics simulations performed for the electron beam and plasma parameters corresponding to that of the experiment conducted in 2016; the beam-plasma interaction is studied for several possible cases of initial beam charge density distributions in plasma, then the measurement of the longitudinal phase space is simulated. The performed simulations show complete saturation of the SMI over the length of the PITZ plasma source and good agreement with the experimental data.In addition, a variable plasma channel length setup for upcoming in-depth experimental studies of the SMI is presented