Recent developments in understanding the physics of laser-produced plasmas

The absorption of intense laser light by a plasma is known to produce a high-energy component of electrons. Even though the hot-electron pressure may be larger than the cold-background pressure, the background temperature can control the self-consistent profile modification. Since temperatures in high-intensity experiments seem to be similar for CO2 and Nd glass lasers, the profile modification may be so severe for CO2 that order-of-magnitude changes in density can occur over microns, leading to a softened electron spectrum. However, the resulting equilibrium of laser pressure balancing plasma pressure is unstable even when flow is properly taken into account. Recent results for self-generated magnetic fields including important kinetic effects are also briefly discussed.