Optical and X-Ray Studies of Marginal Contact Binary RW Dor Using TESS and XMM-Newton Observatories  

作　　者：K.Sriram G.Mamatha Rani 

机构地区：[1]Department of Astronomy,Osmania University 500007,India

出　　处：《Research in Astronomy and Astrophysics》2023年第11期183-197,共15页天文和天体物理学研究（英文版）

基　　金：financial support from the SERB Core Research Grant project,the Government of India;support from the SRF INSPIRE(IF 170314)fellowship program,Government of India。

摘　　要：Marginal short-period contact binaries are important to understand as they pose a different physical scenario than the predicted theoretical model based on the thermal relaxation oscillation mechanism due to their shallow degree of contact.Here we present the optical and X-ray studies of a contact binary source RW Dor using the Transiting Exoplanet Survey Satellite(TESS)and XMM-Newton telescopes.For the first time we report the varying O'Connell effect and explain the asymmetry with a spot model.Based on the new times of minima,we make a robust estimate of the orbital period of the third body at 47.01~0.52 yr with an eccentricity e=0.21.We show that the period-decreasing trend observed in O-C variation can be explained by both conservative mass transfer from primary to secondary and AML via stellar wind.The X-ray luminosity exhibited by RW Dor did not vary significantly on three different occasions and was found to be about 3.34×10~(29)erg s~(-1).Assuming that the quiescent X-ray emission is emitted from an undisturbed loop structure,the loop size is estimated to be 0.6-1×10~(10)cm which is≤Alfvén radius r_A~8×10~(10)cm.

关 键 词：(stars:)binaries(including multiple):close X-rays:binaries stars:activity 

分 类 号：P112[天文地球—天文学]