| Abstract : | Contact Binaries(CBs) of EW-type eclipsing binaries are significant in studying and understanding the fundamental stellar properties and their evolution.Among them, High Mass Ratio Contact Binaries (HMRCBs), especially weak-contact configuration, becomes vital in investigating and testing the formation and evolutionary models of CBs using stellar parameters derived from the high-precision photometric and spectroscopic studies. From the period variation studies, these are known to evolve from the present contact configuration into a broken-contact configuration as per Thermal Relaxation Oscillation (TRO) model or into a deep-contact configuration as per Angular Momentum Loss (AML)model. In the current study, V2840 Cyg (VCyg), a short period EW type weak-contact HMRCB, which is rare of its kind is tested and discussed for the TRO and AML models based on period variation exhibited by VCyg. |
