Plasma source test and simulation results for the underdense plasma lens experiment at the UCLA Neptune Laboratory

The planned plasma lens experiment at the UCLA Neptune Laboratory is descri bed. In the experiment, electron beams with an energy of 16 MeV, a charge o f 4 nC, and a pulse duration of 30 ps [full-width at half-maximnm (FWHM)I a re designed to be produced from the 1.625-cell photoinjector radio-frequenc y gun (f = 2.856 GHz) and PWT linac in the Neptune, The generated beams are passed through a thin underdense argon plasma with a density of low 10(12) cm(-3) range and a thickness of a few centimeters. For this experiment, a LaB6-based discharge plasma source was developed and tested. In this paper, the overview of the planned plasma lens experiment and the test results of the plasma source for various conditions are presented. In addition, compu ter simulations with a 2-1/2 dimensional particle-in-cell code (MAGIC) were performed and the simulation results are shown.