论文标题
Altair非统治搏动的光谱检测
Spectroscopic detection of Altair's non-radial pulsations
论文作者
论文摘要
上下文：快速旋转是早期型恒星的常见特征，但对于模型来说仍然是一个挑战。然而，必须理解其对恒星进化的影响，必须解释许多恒星的观察到的特性。目的：我们希望对快速旋转恒星的性质产生更多的观察性约束，尤其是在其振荡模式下。方法：我们专注于附近的恒星Altair，该Altair被称为非常快速的旋转星，最近估计为313 km/s的赤道速度。我们在六个晚上观察到了高分辨率光谱仪新纳尔瓦尔的恒星，并在2020年9月中断了一晚。结果：我们在光谱的平均线轮廓上检测到了显着的线轮廓变化。他们的时频分析表明，这些变化是由在Altair表面传播的重力惯性波诱导的，具有方位角波数$ M = 10-15 $。通过使用Altair的最新一致性模型对特征的初步计算，我们可以对观察到的波进行首次建模。结论：Altair被称为最明亮的$δ$ Scuti Star。现在，我们看到它是最亮的杂种振荡之星，具有激发的引力惯性波和声波。显然，需要更多的观察和更高级的模型来解释更多细节的观察结果
Context: Rapid rotation is a common feature of early-type stars but which remains a challenge for the models. The understanding of its effect on stellar evolution is however imperative to interpret the observed properties of numerous stars. Aims: We wish to bring more observational constraints on the properties of fast rotating stars, especially on their oscillation modes. Methods: We focus on the nearby star Altair which is known as a very rapidly rotating star with an equatorial velocity estimated recently at 313 km/s. We observed this star with the high-resolution spectropolarimeter Neo-Narval during six nights, with one night of interruption, in September 2020. Results: We detect significant line profile variations on the mean line profile of the spectra. Their time-frequency analysis shows that these variations are induced by gravito-inertial waves propagating at Altair's surface with azimuthal wavenumbers of order $m=10-15$. With a preliminary computation of the eigenspectrum using the most recent concordance model of Altair we can give a first modelling of the observed waves. Conclusions: Altair was known as the brightest $δ$ Scuti star. We now see that it is the brightest hybrid oscillating star with excited gravito-inertial waves and acoustic waves. Clearly, more observations and more advanced models are needed to explain the observations in greater details
