Two-dimensional plasma flow past a laser beam

Analytical results are presented for laser beam deflection rate due to plasma flow when the ponderomotive force (PMF) is static and given. Explicit expressions are obtained in various parameter regimes including that of weak PMF for the case of a coherent (diffraction limited) beam and a beam whose fluctuations are spatially homogeneous, as in the case of a model random phase plate beam. When the Landau damping coefficient, gamma(0), is negligible and the beam is either coherent and cylindrically symmetric, or random with isotropic fluctuations, the deflection rate is obtained as a closed form function of plasma flow Mach number, M. For finite damping, results are expressed in terms of a universal, one dimensional integral parameterized by M and gamma(0). For arbitrary PMF and M small, the problem is identified with one in the theory of random dielectric media. (C) 1997 American Institute of Physics.