论文标题
极端AGB明星的明智观点
A WISE view on extreme AGB stars
论文作者
论文摘要
（删节）变异性是渐近巨型分支（AGB）恒星的关键特性。它们的脉动周期与恒星的亮度和质量损失率（MLR）有关。长周期变量（LPV）和MIRA变量是进化恒星的所有类型变异性中最突出的变量。但是，最红色，最遮盖的AGB恒星在光学中太微弱，并且已经避开了大型可变性调查。我们的目标是通过分析大约2000个来源的明智的W1和W2光曲线（LC）来获取具有较大MLR的LPV样本，镜面上选择了具有11.3 Mu Silicon Carbide粉尘功能的已知C-Star，吸收了11.3 Muilicon Carbide Dust特征，并具有超过1000天的时间。从共同的和新的数据库中检索了epoch光度法，并与窦曲线拟合。还下载并安装了其他可变性调查的光度法。对于316颗最红恒星的子集，构建了光谱能分布（SED），并与中红外（mir）光谱一起使用，并配备灰尘辐射传递程序，以得出MLR。为所有恒星提供了基于明智的LC和拟合数据。受到最近的论文的启发，确定了许多不可变化的OH/IRS。基于对振幅的选择，选择了约750（候选）LPV的样本，其中145个时间超过1000天，其中许多是新的。对于恒星的子集，具有C富含C的极红色物体（ERO）的颜色（ERO）的拟合（和可用的mir光谱）将它们分离成C和O富含的物体。银河色调的数量似乎已完成约5 kpc，并且确定了该类别的太阳能社区中的总灰尘回报率。基于麦哲伦云中的ERO，得出了辐射时期的光度。
(abridged) Variability is a key property of stars on the asymptotic giant branch (AGB). Their pulsation period is related to the luminosity and mass-loss rate (MLR) of the star. Long-period variables (LPVs) and Mira variables are the most prominent of all types of variability of evolved stars. However, the reddest, most obscured AGB stars are too faint in the optical and have eluded large variability surveys. Our goal is to obtain a sample of LPVs with large MLRs by analysing WISE W1 and W2 light curves (LCs) for about 2000 sources, photometrically selected to include known C-stars with the 11.3 mu silicon carbide dust feature in absorption, and Galactic O-stars with periods longer than 1000 days. Epoch photometry was retrieved from the AllWISE and NEOWISE database and fitted with a sinus curve. Photometry from other variability surveys was also downloaded and fitted. For a subset of 316 of the reddest stars, spectral energy distributions (SEDs) were constructed, and, together with mid-infrared (MIR) spectra when available, fitted with a dust radiative transfer programme in order to derive MLRs. WISE based LCs and fits to the data are presented for all stars. Inspired by a recent paper, a number of non-variable OH/IRs are identified. Based on a selection on amplitude, a sample of about 750 (candidate) LPVs is selected of which 145 have periods over 1000 days, many of them being new. For the subset of the stars with the colours of C-rich extremely red objects (EROs) the fitting of the SEDs (and available MIR spectra) separates them into C- and O-rich objects. The number of Galactic EROs appears to be complete up to about 5~kpc and a total dust return rate in the solar neighbourhood for this class is determined. Based on the EROs in the Magellanic Clouds, a bolometric period luminosity is derived.
