Dust density effects on electron density gradient driven lower hybrid waves in magnetized plasma

Electrostatic lower hybrid waves propagating transverse to the external magnetic field in magnetized dusty plasma are investigated, using the fluid equations and also including the effect of density gradient in plasma. Lower hybrid modes are considered important in laboratory, astrophysical as well as space plasmas in interpreting low frequency noises. Unlike other electrostatic waves, lower hybrid waves can resonantly interact with electrons as well as ions in plasma. The dust and gradient terms lead to novel growth of these waves in dusty plasma. A theoretical model is developed to investigate density gradient effects on lower hybrid waves in plasma comprised of electrons, ions and dust particles. The dependence of plasma components' density, strength of magnetic field, temperature and charge of electrons, ions and dust grains on the frequency and growth rate of electrostatic lower hybrid waves has been investigated and presented graphically. It has been observed that the number density of each plasma components directly affects the growth rate. The electrostatic waves are found to grow along the positive electron gradient and the dust effect depends on the gradient length chosen. Above a certain threshold value of gradient length, the waves are found to stabilize. A correlation of the obtained theoretical results with the experimental observations is also discussed.