Gyrating ion beam driven dust acoustic wave instability in a complex plasma.

Through Cerenkov interactions, a low-frequency electrostatic dust acoustic waves (DAWs) have been driven to instabilities by negatively charged dust grains comprised in a plasma cylinder, where a Gyrating ion beam having velocity (v ⊥ θ ⌢ + v b 0 Z ^) has been propagating. For the typically existing parameters of dusty plasma, numerical calculations of phase velocity, unstable wave frequency and growth rate have been performed. With relative density δ (= n 0 i n 0 e ) of negatively charged dust grains, an enhancement in the unstable wave frequency and in the growth rate have been noticed. This is due to the fact that adding of dust into plasma increased the instability, so our growth rate will grow up. Consequently, with the beam density, an increment in the growth rate of unstable dust acoustic wave mode has been reported. It is scaled as 1/3rd of the beam density. Additionally, with the beam energy, an enhancement in the real part frequency of the unstable mode has also been reported. It is scaled as 1/2nd power of beam energy. In research laboratory as well as in astrophysical plasmas, the outcome of this work shall find useful applications. [ABSTRACT FROM AUTHOR]