Improvements to PARMILA

PARMILA is an internationally accepted standard for Monte Carlo simulation of linac and transport line performance. A discussion is presented of several modifications and improvements to this code. A generalized magnet routine allows the simulation of electrostatic and magnetic quadrupoles, solenoids, sextupoles, and octupoles. Optional inclusion of linear fringe fields and/or geometric aberrations is provided for in the quadrupole transformation. The dipole routine has been replaced with a more accurate algorithm. A number of added convenience features - interactive disk storage and retrieval of particle coordinates, individual particle input and observations, an interactively callable test for particle longitudinal stability, and an automated quadrupole tuning procedure - all add to the code's versatility, convenience, and strength as a design tool. 7 refs