Obliquely propagating ion-acoustic double layers in magnetized electron-positron-ion plasma

Ion-acoustic double layers has been studied in magnetized electron-positron-ion plasma. The modified Korteweg-de Vries (m-KdV) is derived using reductive perturbation method. It is found that for the selected set of parameters, the system supports rarefactive (compressive) double layers depending upon the values of cold electron concentration (mu). It is also found that the magnetization affects only the width of the double layer. For a given set of parameter values, as we increases the magnetization, the width of the double layer increases and an increases in the obliqueness theta, where theta is the angle between wave vector and magnetic field, the width of the double layer also increases. The angle of obliqueness theta does not affects the amplitude of the double layer. It is also investigated that for the given set of parameter values, on increasing the positron concentration the amplitude of the rarefactive (compressive) double layer decreases (increases), and the width of the rarefactive (compressive) double layer increases (decreases). The effect of the temperature ratios of ions and positron on the amplitude and width of the double layers are discussed.