论文标题
Kelt-17：化学奇特的AM星和热杂音星球
KELT-17: a chemically peculiar Am star and a hot-Jupiter planet
论文作者
论文摘要
语境。在文献中，几乎不知道绕化学特殊恒星的行星检测。目标。确定杰出行星宿主星kelt-17的详细化学组成。该对象托管一个由Transits检测到的1.31 MJUP的热杂音行星，是迄今为止较大，更快速旋转的行星宿主之一。我们的目的是为该恒星提供完整的化学模式，以将其与化学奇特的恒星进行比较。方法。我们通过光谱合成在行星宿主星Kelt-17中进行了详细的丰度测定。通过拟合Balmer线轮廓并使用程序合成，并与平行平行的ATLAS12模型大气一起估算恒星参数迭代估计并施加了Fe电离平衡。通过不透明度采样（OS）方法计算了任意组成和微扰动速度VMICRO的特定缺陷。通过使用该程序Synthe将合成光谱拟合到16种不同化学物种的金属线上，通过迭代确定丰度。将Kelt-17的完整化学模式与最近发表的AM恒星的平均模式进行了比较。我们通过两种方法估算了恒星半径：a）将合成光谱能分布与可用的光度数据和GAIA视差进行比较，b）使用贝叶斯使用恒星参数使用恒星等速线估计。结果。我们发现Ti，Cr，Mn，Fe，Ni，Zn，Sr，Y，Zr和Ba的过度膨胀，以及Ca和Sc的生物值。值得注意的是，化学模式与最近出版的AM恒星的人一致，然后是Kelt-17是第一个与该类别明确鉴定出的完整化学模式的系外行星宿主。由两种不同方法得出的恒星半径彼此同意，以及先前在文献中获得的恒星半径。
Context. The detection of planets orbiting chemically peculiar stars is very scarcely known in the literature. Aims. To determine the detailed chemical composition of the remarkable planet host star KELT-17. This object hosts a hot-Jupiter planet with 1.31 MJup detected by transits, being one of the more massive and rapidly rotating planet hosts to date. We aimed to derive a complete chemical pattern for this star, in order to compare it with those of chemically peculiar stars. Methods. We carried out a detailed abundance determination in the planet host star KELT-17 via spectral synthesis. Stellar parameters were estimated iteratively by fitting Balmer line profiles and imposing the Fe ionization balance, using the program SYNTHE together with plane-parallel ATLAS12 model atmospheres. Specific opacities for an arbitrary composition and microturbulence velocity vmicro were calculated through the Opacity Sampling (OS) method. The abundances were determined iteratively by fitting synthetic spectra to metallic lines of 16 different chemical species using the program SYNTHE. The complete chemical pattern of KELT-17 was compared to the recently published average pattern of Am stars. We estimated the stellar radius by two methods: a) comparing the synthetic spectral energy distribution with the available photometric data and the Gaia parallax, and b) using a Bayesian estimation of stellar parameters using stellar isochrones. Results. We found overabundances of Ti, Cr, Mn, Fe, Ni, Zn, Sr, Y, Zr, and Ba, together with subsolar values of Ca and Sc. Notably, the chemical pattern agrees with those recently published of Am stars, being then KELT-17 the first exoplanet host whose complete chemical pattern is unambiguously identified with this class. The stellar radius derived by two different methods agrees to each other and with those previously obtained in the literature.
