论文标题
使用苔丝和Brite航天器观察到的明亮主序列A-和B型星的数据分析
Data Analysis of Bright Main-Sequence A- and B-type Stars Observed Using the TESS and BRITE Spacecraft
论文作者
论文摘要
在过去的两年中，我们收到了长时间的光度图观察（V MAG <8）主序列A-和B型星星，由NASA TESS航天器和奥地利 - 帕克纳达式Brite卫星观察到。使用具有特殊元素丰度的金属线A（AM）恒星的苔丝观测值，我们的目标是确定这些恒星是否以及为什么在多个径向和非radial模式中脉动，以及在H-R图的同一区域中的Delta Scuti恒星也是如此。要求BRITE数据调查Cygnus-Lyra视野中的Bright（V大约6个MAG）A和B型星中的脉动，这些恒星已在现已退休的NASA Kepler任务中提议进行观察。 到目前为止，在苔丝观察到的21个AM恒星中，我们发现了一颗Delta SCT星和两个Delta SCT / Gamma Dor混合候选者。在其余的恒星中，我们发现了三个伽马多的候选物，六个恒星显示了可能与脉动相关的或可能不相关的光度变化，而八颗恒星则没有明显的显着光度变异性。对于Brite观察到的A-和B型星，一颗恒星（HR 7403）显示出可能与其B（发射）恒星性质相关的低振幅低频模式。一颗恒星（HR 7179）显示了在先前的开普勒数据中发现的SPB变异性，尽管在Tess或Khepler数据中发现了非常低的振幅可变性，但两颗星（HR 7284和HR 7591）在BRITE数据中没有可变性。对于此处讨论的苔丝和BRITE目标，需要结合结合恒星建模的后续地面和空间光度和光谱观测，以限制恒星参数并了解变异性的性质。
During the last two years we have received long time-series photometric observations of bright (V mag < 8) main-sequence A- and B-type stars observed by the NASA TESS spacecraft and the Austria-Poland-Canada BRITE satellites. Using TESS observations of metallic-line A (Am) stars having peculiar element abundances, our goal is to determine whether and why these stars pulsate in multiple radial and non-radial modes, as do the delta Scuti stars in the same region of the H-R diagram. The BRITE data were requested to investigate pulsations in bright (V around 6 mag) A- and B-type stars in the Cygnus-Lyra field of view that had been proposed for observations during the now-retired NASA Kepler mission. Of the 21 (out of 62 proposed) Am stars observed by TESS so far, we find one delta Sct star and two delta Sct / gamma Dor hybrid candidates. Of the remaining stars, we find three gamma Dor candidates, six stars showing photometric variations that may or may not be associated with pulsations, and eight stars without apparent significant photometric variability. For the A- and B-type stars observed by BRITE, one star (HR 7403) shows low amplitude low frequency modes that likely are associated with its B(emission) star properties; one star (HR 7179) shows SPB variability that is also found in prior Kepler data, and two stars (HR 7284 and HR 7591) show no variability in BRITE data, although very low amplitude variability was found in TESS or Kepler data. For the TESS and BRITE targets discussed here, follow-up ground- and space-based photometric and spectroscopic observations combined with stellar modeling will be needed to constrain stellar parameters and to understand the nature of the variability.
