Abstract Details

Name: Rukmini Jagirdar
Affiliation: Osmania University, Hyderabad
Conference ID: ASI2019_354
Title : Long term Photometric and spectroscopic study of EPIC 211778150 with interesting period and activity variations
Authors and Co-Authors : J.Rukmini, D.Shanti Priya and G. Vinay Kumar
Abstract Type : Poster
Abstract Category : Stars, ISM and Galaxy
Abstract : Short-period contact binaries are important source for determining stellar physical parameters and modelling their evolution. They are known to often show high levels of magnetic activity. In the classification of contact binaries, W-types are defined to be having more massive, intrinsically hotter primary component with high density of stellar spots, lowering their average surface brightness in comparison to the less massive, cooler secondary component. Study of one such variable EPIC 211778150 with a rapid and periodic activity variations is being presented. The observed variations could be due to longitudinal drifts of spots on the surface of one or both the components. Owing to the strange behavior in the light curves from K2 data, it was chosen for photometric and spectroscopic monitoring. The photometric data was analyzed using WD method and the spot distribution with respect to the activity was studied. The observed spectra were compared to synthetic spectra and equivalent widths of H alpha profile were measured. Since the imprints of surface activity was observed both in photometric and spectroscopic results, the variable was further tested for period variation studies. The results of the same are presented to build a conclusive model of the variable. Key words: contact binaries, K2 database, spot activity, period variation studies.