The parametric decay of Alfvén waves into shear Alfvén waves and dust lower hybrid waves

Abstract

The parametric decay instability of Alfvén wave into low-frequency electrostatic dust-lower-hybrid and electromagnetic shear Alfvén waves has been investigated in detail in a dusty plasma in the presence of external/ambient uniform magnetic field. Magnetohydrodynamic fluid equations of plasmas have been employed to find the linear and nonlinear response of the plasma particles for this three-wave nonlinear coupling in a dusty magnetoplasma. Here, relatively high frequency electromagnetic Alfvén wave has been taken as the pump wave. It couples with other two low-frequency internal possible modes of the dusty magnetoplasma, viz., the dust-lower-hybrid and shear Alfvén waves. The nonlinear dispersion relation of the dust-lower-hybrid wave has been solved to obtain the growth rate of the parametric decay instability. The growth rate is maximum for small value of external magnetic field Bs. It is noticed that the growth rate is proportional to the unperturbed electron number density noe. © 2010 American Institute of Physics