[en] Propagation of solitary kinetic Alfvén waves (KAWs) is investigated in small but finite $\mathrm{\beta <!--\; ??\; -->}$ (particle-to-magnetic pressure ratio) collisionless dense plasma whose constituents are nondegenerate warm ions, and relativistic degenerate electrons and positrons. Through the use of reductive perturbation technique, Kortweg–de Vries equation is derived to obtain small amplitude localized wave solution of KAWs. The effects of plasma $\mathrm{\beta <!--\; ??\; -->},$ positron concentration, electron relativistic degeneracy parameter, ion thermal temperature and obliqueness parameter on solitary KAWs are studied. The results of this theoretical investigation are aimed at elucidating characteristics of kinetic Alfvén solitary waves in relativistic degenerate e–p–i plasmas found in dense astrophysical objects specifically neutron stars and white dwarfs. (paper)

[en] Through the use of a reductive perturbation technique, solitary kinetic Alfvén waves (KAWs) are investigated in a low but finite $\mathrm{\beta <!--\; ??\; -->}$ (particle-to-magnetic pressure ratio) dense electron–positron–ion plasma where electrons and positrons are degenerate. The degenerate plasma model considered here permits the existence of sub-Alfvénic compressive solitary KAWs. The influence of r (equilibrium positron-to-ion density ratio), ${\mathrm{\sigma <!--\; ??\; -->}}_{\mathrm{F}}$ (electron-to-positron Fermi temperature ratio), $\mathrm{\beta <!--\; ??\; -->}$ and obliqueness parameter $l_z$ on various characteristics of solitary KAWs are examined through numerical plots. We have shown that there exists a critical value of $l_z$ at which a soliton width attains its maximum value which decreases with an increase in r and ${\mathrm{\sigma <!--\; ??\; -->}}_{\mathrm{F}}.$ It is also found that solitons with a higher energy propagate more obliquely in the direction of an ambient magnetic field. The results of the present investigation may be useful for understanding low frequency nonlinear electromagnetic wave propagation in magnetized electron–positron–ion plasmas in dense stars. Specifically, the relevance of our investigation to a pulsar magnetosphere is emphasized. (paper)