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首页> 外文期刊>The Astrophysical journal >Stellar Evolution with Arbitrary Rotation Laws. IV. Survey of Zero-Age Main-Sequence Models
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Stellar Evolution with Arbitrary Rotation Laws. IV. Survey of Zero-Age Main-Sequence Models

机译:具有任意旋转定律的恒星演化。 IV。零年龄主序模型研究

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A variety of fully two-dimensional, rotating zero-age main-sequence models are presented. The models include four rotation rates for each of five masses between 3 and 20 M☉. The sequence of models for each mass might be regarded as having one small, one moderate, and two fairly rapid rotations. The convective core rotation law and overshooting are determined by two-dimensional, fully implicit hydrodynamic calculations. All models exhibit convective core overshooting. The slowly rotating models show primarily radial convective motion, while the instantaneous flow patterns of the more rapidly rotating models show that the motion is primarily parallel to the rotation axis. The resulting core rotation rate may be fitted by a power law in the distance from the rotation axis, with a cutoff at small distances from the axis, at least for the moderately and rapidly rotating models. The rotation law in the radiative region external to the convective core was chosen to be uniform for the first models calculated, but some models with negative power laws were constructed. These showed that the power law could not be too steep, or the model developed a density inversion near the rotation axis because the pressure gradient must essentially balance the rotational variation, since the gradient of the gravitational potential is too shallow to aid significantly in the balance.
机译:提出了多种全二维,旋转零年龄主序列模型。该模型为3至20M☉之间的五个质量分别包括四个旋转速率。每个质量的模型序列可以被视为具有一个小的,一个中等的和两个相当快速的旋转。对流岩心旋转定律和超调量由二维完全隐含的水动力计算确定。所有模型均表现出对流核心超调。缓慢旋转的模型主要显示径向对流运动,而较快速旋转的模型的瞬时流动模式显示运动主要平行于旋转轴。至少对于适度和快速旋转的模型,可以通过幂律将所得的芯旋转速率拟合为距旋转轴的距离,并且在距轴较小的距离处具有截止值。对于第一个计算的模型,对流核心外部辐射区域的旋转定律被选择为统一的,但是构建了一些具有负幂定律的模型。这些结果表明幂律不可能太陡,或者模型由于压力梯度必须基本平衡旋转变化而在旋转轴附近形成了密度反演,因为重力势的梯度太浅以至于不能显着地帮助平衡。 。

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