The ROSAT bright source 1RXS J201607.0+251645:an active Algol-type binary  

作　　者：Hua-Li Li Yuan-Gui Yang Wei Su Hui-Juan Wang Jian-Yan Wei 

机构地区：[1]National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China [2]National Astronomical Observatories / Urumqi Observatory, Chinese Academy of Sciences, Urumqi830011, China [3]Graduate University of Chinese Academy of Sciences, Beijing 100049, China [4]School of Physics and Electric Information, Huaibei Coal Industry Teachers College, Huaibei235000, China

出　　处：《Research in Astronomy and Astrophysics》2009年第9期1035-1048,共14页天文和天体物理学研究（英文版）

基　　金：Supported by the National Natural Science Foundation of China(Grant Nos.10778707 and 10473013)

摘　　要：1RXS J201607.0＋251645 is identified as an eclipsing binary. We present preliminary observations in the V band with the 0.6-m telescope for three years and extensive observations in the V and R bands with the 0.8-m telescope for six nights, respectively. The light curve of the system is E13 type. Five light minimum times were obtained and the orbital period of 0.388058^d（±0.00044d） is determined. The photometric solution given by the 2003-version of the Wilson-Devinney program suggests that the binary is a semidetached system with photometric mass ratio 0.895（±0.006）, which is probably comprised of a G5 primary and an oversized K5 secondary. The tess massive component has completely filled its Roche lobe, while the other one almost fills its Roche lobe with a filling factor of 93.4%. The system shows a varying O＇Connell effect in its phase folded diagrams from 2005 to 2007, and is X-ray luminous with log Lx/Lbol - -3.27. Possible mechanisms to account for these two phenomena are discussed. Finally, we infer that the binary may be in thermal oscillation or may evolve into a contact binary.1RXS J201607.0＋251645 is identified as an eclipsing binary. We present preliminary observations in the V band with the 0.6-m telescope for three years and extensive observations in the V and R bands with the 0.8-m telescope for six nights, respectively. The light curve of the system is E13 type. Five light minimum times were obtained and the orbital period of 0.388058^d（±0.00044d） is determined. The photometric solution given by the 2003-version of the Wilson-Devinney program suggests that the binary is a semidetached system with photometric mass ratio 0.895（±0.006）, which is probably comprised of a G5 primary and an oversized K5 secondary. The tess massive component has completely filled its Roche lobe, while the other one almost fills its Roche lobe with a filling factor of 93.4%. The system shows a varying O＇Connell effect in its phase folded diagrams from 2005 to 2007, and is X-ray luminous with log Lx/Lbol - -3.27. Possible mechanisms to account for these two phenomena are discussed. Finally, we infer that the binary may be in thermal oscillation or may evolve into a contact binary.

关 键 词：stars： binaries： close -- stars： binaries： eclipsing -- stars： individual： 1RXSJ201607.0＋251645 HD 339946 

分 类 号：TP301.6[自动化与计算机技术—计算机系统结构] V474[自动化与计算机技术—计算机科学与技术]