论文标题
当光盘不在时，星星将播放：类似Nova的变量KR AUR中的动态质量，带有一小撮积聚
When the disc's away, the stars will play: dynamical masses in the nova-like variable KR Aur with a pinch of accretion
论文作者
论文摘要
我们在低状态下获得了NOVA样变量kr aurigae的时间分辨光学测定和光谱。频谱揭示了一个轻巧的白色矮人和一个中间矮人的同伴。使用Companion Star的$ i $ band椭圆形调制，我们将二进制轨道时期改进为$ p = 3.906519 \ pm 0.000001 $ h。光曲线和光谱由于情节增生而显示出耀斑的活性。这些事件之一在27.4分钟内产生了亮度振荡，我们建议与可能在27.4或54.8分钟处可能是磁白矮人的旋转期有关。光谱建模为同伴星提供了一种M4-5的光谱类型，$ t_ {1} = 27148 \ pm 496 $ k，$ \ log G = 8.90 \ pm 0.07 $，$ \ log（\ mathrm {he/h H} By simultaneously fitting absorption- and emission-line radial velocity curves and the ellipsoidal light curve, we determined the stellar masses to be $M_1 = 0.94^{+0.15}_{-0.11}~$ $M_\odot$ and $M_2 = 0.37^{+0.07}_{-0.07}~$ $ m_ \ odot $分别用于白色矮人和M-dwarf，以及$ 47^{+1^{\ rm o}} _ { - 2^{\ rm o}} $的轨道倾斜度。最后，我们分析了系统的时间分辨光谱验证，当该系统处于17.1的$ $ $带幅度时，比低状态更明亮。在此中间状态下，线曲线包含一个发射s波，相对于白色矮人的运动，延迟$ \ simeq 0.2 $轨道循环，类似于高状态下的SW Sextantis恒星中观察到的。
We obtained time-resolved optical photometry and spectroscopy of the nova-like variable KR Aurigae in the low state. The spectrum reveals a DAB white dwarf and a mid-M dwarf companion. Using the companion star's $i$-band ellipsoidal modulation we refine the binary orbital period to be $P = 3.906519 \pm 0.000001$ h. The light curve and the spectra show flaring activity due to episodic accretion. One of these events produced brightness oscillations at a period of 27.4 min, that we suggest to be related with the rotation period of a possibly magnetic white dwarf at either 27.4 or 54.8 min. Spectral modelling provided a spectral type of M4-5 for the companion star and $T_{1}=27148 \pm 496$ K, $\log g=8.90 \pm 0.07$, and $\log (\mathrm{He/H})= -0.79^{+0.07}_{-0.08}~~$ for the white dwarf. By simultaneously fitting absorption- and emission-line radial velocity curves and the ellipsoidal light curve, we determined the stellar masses to be $M_1 = 0.94^{+0.15}_{-0.11}~$ $M_\odot$ and $M_2 = 0.37^{+0.07}_{-0.07}~$ $M_\odot$ for the white dwarf and the M-dwarf, respectively, and an orbital inclination of $47^{+1^{\rm o}}_{-2^{\rm o}}$. Finally, we analyse time-resolved spectroscopy acquired when the system was at an $i$-band magnitude of 17.1, about 1.3 mag brighter than it was in the low state. In this intermediate state the line profiles contain an emission S-wave delayed by $\simeq 0.2$ orbital cycle relative to the motion of the white dwarf, similar to what is observed in SW Sextantis stars in the high state.
