The NEPTUNE laboratory, under construction at UCLA, will be a user facility for exploring concepts useful for advanced accelerators. The primary programmatic goal for the laboratory is to inject extremely high-quality electron bunches into a laser-driven plasma beat wave accelerator and explore ideas for extracting a high-quality Delta E/E<0.1, epsilon <10 pi mm mrad, high-energy (100 MeV) beam from a plasma structure operating at about 1 THz and about 3 GeV/m. The lab will combine an upgraded MARS CO_2 laser and the state-of-the-art SATURNUS RF gun and linac, also undergoing an upgrade. The new MARS laser will be about 1 TW (100 J, 100 ps), up from 0.2 TW (70 J, 350 ps). This allows for doubling the spot size of the laser beam and thereby quadrupling the interaction length while still driving gradients of 3 GeV/m. The large diameter of the accelerating structure relative to the injected electron bunches (10:1 ratio) will minimize the deleterious effects of the radial dependence of the accelerating field and soften the radial focusing thus permitting, in principle, the extraction of a high-quality accelerated beam. 378 ICFA Second Generation Plasma Acceleration Workshop unavailable 3 94 Accelerator RF systemsCollective acceleratorsElectron acceleratorsElectron beam focusingElectron gunsElectron sourcesLinear collidersParticle beam extractionLinear accelerators [A2915D], Beams in particle accelerators [A2921], Electron beams and electron optics [A4180D], Electron sources [A2925B], Particle beam handling and diagnostics [B7410B], Power convertors and power supplies to apparatus [B8360], Electron emission, materials and cathodes [B2320], Particle sources and targets [B7410D]second generation beatwave experiments, UCLA, NEPTUNE laboratory, electron bunches, laser-driven plasma beat wave accelerator, upgraded MARS CO/sub 2/ laser, SATURNUS RF gun, linac, interaction length, deleterious effects, radial focusing, high-quality accelerated beam extraction, 1 THz, 1 TW, 100 MeV, CO/sub 2/ 13th Advanced ICFA Beam Dynamics Workshop and 1st ICFA Novel and Advanced Accelerator Workshop. Kyoto, Japan. 14-18 July 1997. Frequency 1.0E+12 Hz Power 1.0E+12 W Electron volt energy 1.0E+08 eV English Conference Paper 3 1998 Nuclear Instruments & Methods A, vol. 410 192 2007-07-27T23:53:35-07:00 378-87 1997