Design and beam dynamics simulations of an S-band photocathode rf gun

We are building an S-band photocathode rf gun as an injector to a 30 MeV electron linac for FEL applications. Here we discuss details of design simulations performed using superfish and gdfidl and compare with results of cold tests performed on prototype cells of the photocathode rf gun. We also discuss beam dynamics simulations performed using parmela and report results from simulations to achieve a normalized transverse rms emittance of about 1π  mm mrad for a 10 ps pulse with 1 nC charge in the presence of a solenoid magnetic field used for emittance compensation.