Revised Stellar Parameters for V471 Tau, A Post-common Envelope Binary in the Hyades
Revised Stellar Parameters for V471 Tau, A Post-common Envelope Binary in the Hyades
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DOI：
10.3847/1538-3881/ac390f
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发表时间：
2021-11
期刊：
影响因子：
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通讯作者：
P. Muirhead;J. Nordhaus;M. Drout
中科院分区：
文献类型：
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作者：
P. Muirhead;J. Nordhaus;M. Drout
V471 Tau是后通用的二进制二进制文件，由YHYADES星团中的Da White Dwarf和K-Type主序列明星组成。我们分析了V471 TAU的公开光度法和光谱法，以修改系统的恒星和轨道参数。我们使用了档案k2光度法，档案中的哈勃空间望远镜光谱，并发布了K型恒星的径向速度测量值。我们采用高斯工艺适合通过主序列恒星对系统通量的旋转调制，我们首次回收了白矮人在主序列恒星前的过渡。由于重力微覆盖在过境过程中，因此过渡比纯粹的几何掩星所预期的要浅，这对白矮人质量造成了额外的限制。鉴于性能的年龄和金属性，我们对主要序列恒星的修订质量和半径与单星进化模型一致。但是，正如文献中先前指出的那样，白矮人过于巨大，太热了，无法成为单星演变的结果，鉴于羟基的年龄，可能是合并情景的产物。我们独立估计通用包膜时系统的条件，这将导致当今测得的轨道参数。
V471 Tau is a post-common-envelope binary consisting of an eclipsing DA white dwarf and a K-type main-sequence star in the Hyades star cluster. We analyzed publicly available photometry and spectroscopy of V471 Tau to revise the stellar and orbital parameters of the system. We used archival K2 photometry, archival Hubble Space Telescope spectroscopy, and published radial-velocity measurements of the K-type star. Employing Gaussian processes to fit for rotational modulation of the system flux by the main-sequence star, we recovered the transits of the white dwarf in front of the main-sequence star for the first time. The transits are shallower than would be expected from purely geometric occultations owing to gravitational microlensing during transit, which places an additional constraint on the white-dwarf mass. Our revised mass and radius for the main-sequence star is consistent with single-star evolutionary models given the age and metallicity of the Hyades. However, as noted previously in the literature, the white dwarf is too massive and too hot to be the result of single-star evolution given the age of the Hyades, and may be the product of a merger scenario. We independently estimate the conditions of the system at the time of common envelope that would result in the measured orbital parameters today.