Kadomtsev-Petviashvili equation for acoustic wave in quantum pair plasmas

The Kadomtsev-Petviashvili equation is derived for two-dimensional propagations of electrostatic solitons in unmagnetized dense pair-plasmas. The reductive perturbation method is employed and two-dimensional electrostatic potential hump structures are obtained. The conditions for a stable two-dimensional solitary structure are discussed using energy consideration method. The numerical results are also presented by considering the parameters for the outer layers of white dwarfs/neutron stars.