Accretion in dipole magnetic fields: flow structure and X-ray emission of accreting white dwarfs
Accretion in dipole magnetic fields: flow structure and X-ray emission of accreting white dwarfs
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偶极子磁场中的吸积：吸积白矮星的流动结构和 X 射线发射
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
Max
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文献类型：
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作者：
J. B. G. Canalle;C. Saxton;Kinwah Wu;M. Cropper;Gavin Ramsay;Msslucl;State University of Rio de Janeiro;Max
场通道吸积流发生在各种天体中，包括金牛T星、磁灾变变星和X射线双星。我们考虑一个曲线坐标系，并推导出一个一般的流体动力学公式吸积到恒星的偶极磁场所限制的恒星物体。求解流体动力学方程以确定流动的速度、密度和温度分布。我们使用吸积磁性白矮星作为天体物理学应用的一个说明性的例子。我们的计算表明，压缩加热由于场的几何形状是一样重要的辐射冷却和重力在确定吸积白矮星的激波后流的结构。概括的制定吸积流通道的高阶领域和其他天体物理系统的应用进行了讨论。
Field-channelled accretion flows occur in a variety of astrophysical objects, including T Tauri stars, magnetic cataclysmic variables and X-ray pulsars. We consider a curvilinear coordinate system and derive a general hydrodynamic formulation for accretion onto stellar objects confined by a stellar dipole magnetic field. The hydrodynamic equations are solved to determine the velocity, density and temperature profiles of the flow. We use accreting magnetic white-dwarf stars as an illustrative example of astrophysical applications. Our calculations show that the compressional heating due to the field geometry is as important as radiative cooling and gravity in determining the structure of the post-shock flow in accreting white-dwarf stars. The generalisation of the formulation to accretion flows channelled by higher-order fields and the applications to other astrophysical systems are discussed.