期刊
ASTRONOMY & ASTROPHYSICS
卷 557, 期 -, 页码 -出版社
EDP SCIENCES S A
DOI: 10.1051/0004-6361/201322195
关键词
stars: fundamental parameters; binaries: eclipsing; binaries: spectroscopic
资金
- STFC
- STFC [ST/H005307/1] Funding Source: UKRI
- Science and Technology Facilities Council [ST/H005307/1] Funding Source: researchfish
The eclipsing binary LL Aqr consists of two late-type stars in an eccentric orbit with a period of 20.17 d. We use an extensive light curve from the SuperWASP survey augmented by published radial velocities and UBV light curves to measure the physical properties of the system. The primary star has a mass of 1.167 +/- 0.009 M-circle dot and a radius of 1.305 +/- 0.007 R-circle dot. The secondary star is an analogue of the Sun, with a mass and radius of 1.014 +/- 0.006 M-circle dot and 0.990 +/- 0.008 R-circle dot respectively. The system shows no signs of stellar activity: the upper limit on spot-induced rotational modulation is 3 mmag, it is slowly rotating, has not been detected at X-ray wavelengths, and the calcium H and K lines exhibit no emission. Theoretical stellar models provide a good match to its properties for a sub-solar metal abundance of Z = 0.008 and an age of 2.5Gyr. Most low-mass eclipsing binary systems are found to have radii larger than expected from theoretical predictions, blamed on tidally-enhanced magnetic fields in these short-period systems. The properties of LL Aqr support this scenario: it exhibits negligible tidal effects, shows no signs of magnetic activity, and matches theoretical models well.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据