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Using kinetic theory, some Electrostatic and Electromagnetic modes have been studied. New dispersion relations based on Maxwellian and non-Maxwelian velocity distributions are obtained for Langmuir, Dust Ion Acoustic, Dust Acoustic, O-Mode and X-Mode. Instability arisen due to anisotropy of temperature has been calculated under same environment. To illustrate the results graphically, we have plotted the phase velocity squared and the growth rate versus frequency. The real frequency and the growth rate of the modes are calculated by using kappa and generalized (r,q) distribution functions and results are compared with those of Maxwellian distribution. It is noted that in the limit, (r,q) distributions and kappa distributions, the non-Maxwellian functions reduce to Maxwellian.

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Dr. Sadia Zaheer bagged her PhD and MsC at Govt. College University, Lahore in 2009 and 2001 respectively. Currently she is Assistant Professor at Forman Christian College. Her field of study is Plasma Physics.

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