The aim is to state the properties of ion acoustic solitary waves in course of collision and extract characteristics of the daughter wave in a magnetized electron–ion plasma. The magnetized plasma medium that is a constituent of white dwarfs and astrophysical plasmas that possesses relativistically degenerate electrons and thermal ions in the presence of a constant background magnetic field. The model is based on the extended Poincar´e–Lighthill–Kuo (ePLK) method where a set of Korteweg–de Vries equations is obtained to show the phase shifts of colliding waves together with the amplitude and width of the born daughter solitary waves. The numerical results and presented figures regarding the amplitude and width of solitons provide a description of the influence of plasma parameters on soliton interactions, namely ion to electron temperature ratio (σ i), ion cyclotron frequency (ωci), and angle between magnetic field and collision line (θ) together with their interplay in shaping the character of solitary waves. It is concluded that only rarefactive electrostatic non-linear waves are able to propagate in such plasma media. The daughter wave amplitude possesses a scaling behaviour regarding the impact angle. Interplay of the parameters on the phase shifts is presented. Ratio of amplitude and width of the daughter wave is directly proportional to the background field, the impact angle controls its maximum. It is observed that the magnetic field elevates ratio of the solitary wave amplitude to width leading it to a shorter life and hence interaction range with neighbouring sites.
