Magnetosonic waves are studied in the presence of degenerate pressure due to Landau diamagnetic levels and Pauli spin magnetization with strong magnetic field in quantum degenerate electron-ion plasma. A linear dispersion relation of low frequency propagation wave in the direction of magnetic field is derived that strongly depends on the magnetic field while in classical regime this field has no such a role. In the presence of quantization of orbital motion and spin magnetization, new propagation modes of quantum plasmas are also explored. It is noted that quantum acoustic velocity and spin magnetization energy affect the Alfven mode propagation. The quantum effects are incorporated through the Bohm potential, Landau pressure due to Landau quantization of magnetic field and magnetization energy due to spin effect. The current model in the context of Landau diamagnetic pressure along with spin magnetization is sufficient for studying the astrophysical plasma environment existing in the compact systems e.g., white dwarfs and neutron stars.and while the field of interior core of NS can reach ;10 11 Tesla or even may be higher [9][10][11]. Further this field may be increased by a factor 10 3 ∼10 4 due to the rotational movement of stars RECEIVED

Linear properties of low‐frequency electromagnetic shear Alfven waves (SAWs) are studied in quantum electron‐positron‐ion plasmas with effect of arbitrary temperature degeneracy for magnetized (ω2≪ωnormalci2≪ωce,cp2) and unmagnetized (ωnormalci2≪ω2≪ ωce,cp2) ions by using the quantum hydrodynamic model. Dispersion relations are derived for nearly degenerate (ξ=expμKBTnormale,normalp≫1) and nearly non‐degenerate (ξ=expμKBTnormale,normalp≪1) plasmas. Bohm potential due to density correlation and temperature degeneracy due to Fermi–Dirac statistics of electron–positron, and their effects on the dispersion of SAWs are studied in detail both analytically and numerically. The relevance of the work regarding dense astrophysical plasmas is highlighted.