Structure of driven Alfvén waves with oblique magnetic field and dissipation

The quasi-resonant behavior of linear Alfven waves in one-dimensional magnetized weakly resistive plasmas with the slightly inclined equilibrium magnetic field is studied. The analysis concentrates on the behavior of the gamma-component of the velocity, nu, which is the component perpendicular both to the inhomogeneity direction and to the equilibrium magnetic field, and the z-component of the velocity, w, which is the component along the inhomogeneity direction. It is shown that the behavior of nu and w is described by the functions F(sigma; Lambda) and G(sigma; Lambda), where s is the dimensionless distance along the inhomogeneity direction and the parameter Lambda characterizes the relative importance of resistivity and the magnetic field inclination near the quasi-resonant position. The functions F( sigma; Lambda) and G(sigma; Lambda) are generalizations of the F and G functions introduced by Goossens, Ruderman, and Hollweg [Sol. Phys. 157, 75 (1995)] and coincide with them for Lambda = 0. The behavior of F( sigma; Lambda) and G(sigma; Lambda) is studied numerically for different values of Lambda. It changes from monotonic to oscillatory when Lambda is increased. It is shown that the connection formulas giving the jumps of w and the perturbation of the total pressure across the quasi-resonant layer and the rate of energy dissipation in the quasi-resonant layer are independent of the inclination angle. (C) 1999 American Institute of Physics. [S1070- 664X(99)00703- X].