Effect of interaction of the various modes on the radial velocity curves of the polytropic models of rotationally and tidally distorted pulsating variable stars

Abstract

In our previous work, we developed a model to study the effects of rotation and/or tidal distortions on anharmonic radial oscillations and hence on the radial velocity curves of the polytropic models of pulsating variable stars. We considered the first three modes (fundamental and the next two higher modes) for the polytropic models of index 1.5 and 3.0 in that work. In the present paper, we are further extending our previous work to study the effect of the interaction of various modes on anharmonic radial oscillations and hence on radial velocity curves of the rotationally and/or tidally distorted polytropic models of pulsating variable stars. For this purpose, we have considered the following cases: (i) fundamental mode (ii) fundamental and the first mode, (iii) fundamental and the next two modes and finally (iv) fundamental and the next three higher modes of pulsation in our study. The objective of this paper is also to investigate whether the interaction of various modes affects the results of our previous study or not. The results of this study show that the interaction of the fundamental mode with higher modes appreciably changes the shape of the radial velocity curve of rotationally distorted and rotationally and tidally distorted polytropic models of pulsating variable stars.