Electrostatic Rayleigh-Taylor Mode in Electron-Positron-Ion Quantum Plasma

Abstract

Electrostatic Rayleigh-Taylor (ERT) mode/instability is studied in a non-uni-form quantum magnetoplasma, whose constituents are electrons and positrons with fraction of ions. The effects of quantum corrections ( i.e. Bohm potential and temperature degeneracy) and magnetic field on ERT mode are investigated with astrophysical plasma application. A generalized dispersion relation is deduced under the drift wave approximation. The presence of positron makes the dispersion relation a cubic equation. Different roots of both real and imaginary parts of the RT mode are examined by applying the Cardano’s method of solving the cubic equation. The dispersion relation and the growth rates of RT instability are examined both analytically and numerically with effects of electron and positron density, and magnetic field variations. It is shown that the magnetic field and positron density have stabilizing effectuates on ERT mode while due to electron density the mode becomes unstable. The present work is antici-pated to be of physical relevance in the studies of laboratory laser-produced plasmas as well as in the study of compact magnetized astrophysical objects like white dwarfs.