Role of Jeans Instability in Multi-Component Quantum Plasmas in the Presence of Fermi Pressure

The quantum hydrodynamic model is employed to investigate the effects of gravitational potential on multi-component dusty plasmas. The effects of Fermi temperature ratios of ions to electrons (T_Fi/T_Fe) and positrons to electrons (T_Fp/T_Fe) have been calculated and presented graphically. It is observed that an increase in the Fermi temperature ratios of ions to electrons and positrons to electrons stabilizes the Jeans instability as the mode phase speed increases with these ratios. In the absence of the statistical effects due to Fermi pressure, the dispersion is weak. The stability criteria are calculated for each case separately.