High brightness photoinjectors for superconducting
linac-based FELs are developed, optimized and
characterized at the Photo Injector Test facility at DESY
in Zeuthen (PITZ). Last year the facility was significantly
upgraded with a new prototype photocathode laser system
capable of producing homogeneous ellipsoidal pulses.
Previous simulations have shown that the corresponding
pulses allow the production of high brightness electron
bunches with minimized emittance. Furthermore, a new
normal conducting RF gun cavity was installed with a
modified two-window waveguide RF feed layout for
stability and reliability tests, as required for the European
XFEL. Other relevant additions to the facility include
beamline modifications for improved electron beam
transport through the PITZ accelerator, refinement of both
the cooling and RF systems for improved parameter
stability, and preparations for the installation of a plasma
cell. This paper describes the facility upgrades and reports
on the operational experience with the new components.