论文标题
通过GPX调查发现具有不寻常的白色矮人的异常色度的二元前二进制
Discovery of a pre-cataclysmic binary with unusual chromaticity of the eclipsed white dwarf by the GPX Survey
论文作者
论文摘要
我们报告了一个相对明亮的黯然失色的二进制系统的发现，该系统由白色矮人和一个主序列K7星组成，具有明显的色球和斑点活性迹象。该系统的光曲线显示$ \ sim0.2 $ mag椭圆形变异性，周期为0.297549d，白色矮人的总食物很短。根据我们对光谱和光度数据的分析，我们估计了系统的参数。 K7V恒星潮汐变形，但不填充其Roche Lobe（填充因子约为0.86）。轨道倾斜度为$ i = 73^\ circ.1 \ pm 0^\ circ.2 $，质量比为$ q = m_2/m_1 \约0.88 $。 K7V星的参数为$ M_2 \大约0.64 $ m $ _ {\ odot} $，$ r_2 = 0.645 \ pm 0.012 $ r $ $ _ {\ odot} $，$ t_2 \ $ t_2 \ y 4070 $ k。白矮人的参数为$ M_1 \大约0.72 $ m $ _ {\ odot} $，$ r_1 = 0.013 \ pm 0.003 $ r $ _ {\ odot} $，$ t_1 = 8700 = 8700 \ pm 1100 $ k。不同频段中的光度观测表明，日食的最大深度位于\ textit {sdss r}滤波器中，这对于白色矮人和晚期主序列的系统而言是不寻常的。我们怀疑该系统是公共包膜二进制恒星进化的产物，并且白矮人从次级恒星（所谓的低核速率极性，larp）中积聚了恒星风。
We report the discovery of a relatively bright eclipsing binary system, which consists of a white dwarf and a main sequence K7 star with clear signs of chromospheric and spot activity. The light curve of this system shows $\sim0.2$mag ellipsoidal variability with a period of 0.297549d and a short total eclipse of the white dwarf. Based on our analysis of the spectral and photometric data, we estimated the parameters of the system. The K7V star is tidally deformed but does not fill its Roche lobe (the filling factor is about 0.86). The orbital inclination is $i=73^\circ.1\pm 0^\circ.2$, the mass ratio is $q=M_2/M_1\approx 0.88$. The parameters of the K7V star are $M_2\approx 0.64$M$_{\odot}$, $R_2=0.645\pm 0.012$R$_{\odot}$, $T_2\approx 4070$K. The parameters of the white dwarf are $M_1\approx 0.72$M$_{\odot}$, $R_1=0.013\pm 0.003$R$_{\odot}$, $T_1=8700\pm 1100$K. Photometric observations in different bands revealed that the maximum depth of the eclipse is in the \textit{SDSS r} filter, which is unusual for a system of a white dwarf and a late main sequence star. We suspect that this system is a product of the evolution of a common envelope binary star, and that the white dwarf accretes the stellar wind from the secondary star (the so-called low-accretion rate polar, LARP).
