Effects of Rotation on the Spatial Structure of Wolf-Rayet Winds

Cassineli 9417186 Wolf-Rayet （WR）星的风具有非常大的质量损失率和快速的终端速度。由此产生的风动量通量大大超过了在紧急辐射场中的动量通量。与O型星的风相比，WR型星的风似乎加速得相当慢，因此适度的恒星旋转可以导致恒星赤道区域密度的显著增强。本研究旨在建立二维风模型，并利用“风压缩带”模型研究这种结构对WR星观测的影响。它基于“风压缩盘”模型，该模型是为快速旋转的Be星而开发的。对于以10%到20%的临界速度旋转的恒星，风压缩可以解释WR恒星的一些令人困惑的观测特性，例如为什么只有一些WR恒星表现出极化，为什么有紧密伴星的WR恒星可以有强烈的x射线发射。此外，我们将使用我们的二维WCZ模型研究发光蓝变量（LBVs）。这些天体被认为是WR阶段的前兆。观测到lbv有缓慢的风，有些似乎具有轴对称结构（例如船底座AG），这表明这些恒星也是应用我们的旋转风模型的良好候选者。也有证据表明WR恒星的非热射电辐射，并且这些风可能是高能粒子产生的来源。由于这些观测，磁场也将包括在WCZ图像中。这将使我们能够重新解释观测证据，也使我们能够研究磁场对风动力学的影响。* * *

Cassineli 9417186 Wolf-Rayet (WR) stars have winds with very large mass-loss rates and fast terminal speeds. The resultant wind momentum flux greatly exceeds that in the emergent radiation field. In contrast with the winds of O stars, the WR winds appear to accelerate rather slowly so that moderate stellar rotation can lead to a significant enhancement of the density in the equatorial region of the stars. This research is to develop two-dimensional models of the winds and to investigate the consequences of the structure for the observations of WR stars using the "Wind Compression Zone" model. It is based on the "Wind Compression Disk" model, which was developed for rapidly rotating Be stars. For stars rotating at about 10% to 20% critical, the wind compression may explain a number of puzzling observational properties of WR stars, such as why only some WR stars show polarization and why WR stars with compact companions can have strong X-ray emission. In addition, we will study the Luminous Blue Variables (LBVs) using our 2-D WCZ model. These objects are thought to be a precursor stage to the WR phase. LBVs are observed to have slow winds, and some appear to have axisymmetric structure (e.g. AG Carinae), which indicates that these stars are also good candidates for the application of our rotating wind model. There is also evidence of non-thermal radio emission from WR stars and that the winds might be source of high energy particle production. Because of these observations magnetic fields will also be included in the WCZ picture. This will allow us to re-interpret the observational evidence, and also allow us to investigate the consequences of the fields on the wind dynamics. ***