论文标题
HD 133729：围绕主要序列B型星的轨道上的蓝色大振幅脉动器
HD 133729: A blue large-amplitude pulsator in orbit around a main-sequence B-type star
论文作者
论文摘要
蓝色的大振幅脉动器（BLAPS）形成了一小组以30分钟为单位的径向模式脉动的热对象。 Proposed evolutionary scenarios explain them as evolved low-mass stars: either ~0.3 M$_\odot$ shell-hydrogen-burning objects with a degenerated helium core, or more massive (0.5 - 0.8) M$_\odot$ core-helium-burning stars, or ~0.7 M$_\odot$ surviving companions of type Ia supernovae.因此，它们的起源仍有待确定。使用传输系外行星调查卫星的数据，我们发现HD 133729是由晚期B型主序列恒星组成的二进制二进制文件。 Blap脉动脉动，周期为32.37分钟，以$（-7.11 \ pm 0.33）\ times 10^{ - 11} $减少。由于较明亮的伴侣的轻稀释，观察到的脉动幅度比其他空白小得多。从可用的光度法中，我们得出了最大光的时间，这通过O-C图揭示了恒星的二元性质。该图显示了我们归因于系统中的轻轨时间效应的周期为23.08433 d的变化。对这些变化的分析允许得出围绕二进制质量中心围绕的大小轨道的光谱参数。通过分析其光谱能量分布来证实系统中热伴侣的存在，该分布也用于将组件放置在H-R图中。所获得的空白位置完全与班级其他成员的位置完全吻合。估计的V〜11 mag和Gaia的距离小于0.5 kpc，Blap是最亮，最接近所有已知的单曲的距离。在验证此类变量的进化场景中，它可能成为线索对象。我们认为，如果组件是同时的，则不排除大声的低质量祖细胞，并且组件之间没有质量转移。
Blue large-amplitude pulsators (BLAPs) form a small group of hot objects pulsating in a fundamental radial mode with periods of the order of 30 minutes. Proposed evolutionary scenarios explain them as evolved low-mass stars: either ~0.3 M$_\odot$ shell-hydrogen-burning objects with a degenerated helium core, or more massive (0.5 - 0.8) M$_\odot$ core-helium-burning stars, or ~0.7 M$_\odot$ surviving companions of type Ia supernovae. Therefore, their origin remains to be established. Using data from Transiting Exoplanet Survey Satellite, we discovered that HD 133729 is a binary consisting of a late B-type main-sequence star and a BLAP. The BLAP pulsates with a period of 32.37 min decreasing at a rate of $(-7.11 \pm 0.33)\times 10^{-11}$. Due to light dilution by a brighter companion, the observed amplitude of pulsation is much smaller than in other BLAPs. From available photometry, we derived times of maximum light, which revealed the binary nature of the star via O-C diagram. The diagram shows variations with a period of 23.08433 d that we attribute to the light-travel-time effect in the system. The analysis of these variations allowed to derive the spectroscopic parameters of the BLAP's orbit around the center of the mass of the binary. The presence of a hot companion in the system was confirmed by the analysis of its spectral energy distribution, which was also used to place the components in the H-R diagram. The obtained position of the BLAP fully agrees with the location of the other members of the class. With the estimated V~11 mag and the Gaia distance of less than 0.5 kpc, the BLAP is the brightest and the nearest of all known BLAPs. It may become a clue object in the verification of the evolutionary scenarios for this class of variable. We argue that low-mass progenitors of the BLAP are excluded if the components are coeval and no mass transfer between the components took place.
