Interaction of laser-produced plasmas with large magnetoplasmas

We will present experiments on the interaction of dense laser-produced plasmas with a large mangetoplasma. A high-energy laser ($>$20 J) coupled to the Large Plasma Device (LAPD) at UCLA allows unique experiments on laser driven shocks that can approach the collisionless regime. Focused laser intensities around $10^{13}$ W/cm$^2$ produce an ablating plasma-plume with expansion velocities of several 100 km/s. Prior to the laser pulse an ambient plasma with a size of 18 m lengths and 50 cm diameter at $4x10^{12}\ cm^{-3}$ and T$_e$=5 eV is created in an axial magnetic field of 600-1800 G. We will present measurements of Alfven waves radiated from the laser-produced plasma, as well as a characterization of the evolution and particle distribution of the laser-produced plasma `piston'.