Collisionless solar wind: 1. Constant electron temperature
Collisionless solar wind: 1. Constant electron temperature
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无碰撞太阳风：1.恒定的电子温度
DOI：
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发表时间：
1970
期刊：
影响因子：
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通讯作者：
J. V. Hollweg
中科院分区：
文献类型：
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作者：
J. V. Hollweg
讨论了太阳风的 2 流体模型，其中电子在恒温下经过流体动力学处理，并且假设质子在距太阳一定距离处（它们已经是超音速的）变得无碰撞。包括径向磁场、径向引力场和电场；电场产生于准中性条件，是该模型的一个重要特征。平行于和垂直于磁场的体积速度、浓度和质子温度等量直接根据质子分布函数进行讨论；因此，粘度和热传导被自动包含在内。主要结果是，如果电子变得无碰撞点（距离太阳 10-20 个太阳半径）附近的电子温度约为 106 °K，则地球轨道上的流速超过 300 公里/秒，平均质子温度约为 10,000 °K。这两个数字都高于双流体流体动力学模型获得的数字。远离模型底部的速度变化为Te1/2，并且对底部的温度或速度或底部的位置相对不敏感。质子的热各向异性 T∥/T⊥ 预计约为 50。
A 2-fluid model for the solar wind is discussed, in which the electrons, at constant temperature, are treated hydrodynamically and the protons are assumed to become collisionless, at a distance from the sun at which they are already supersonic. A radial magnetic field is included, with radial gravitational and electric fields; the electric field arises from the condition of quasi-neutrality and is an important feature of the model. Quantities such as bulk velocity, concentration, and proton temperatures parallel and perpendicular to the magnetic field are discussed directly in terms of the proton distribution function; viscosity and heat conduction are thus automatically included. The principle result is that if the electron temperature in the vicinity of the point where the electrons become collisionless (10–20 solar radii from the sun) is of the order 106 °K, the flow velocity at the orbit of the earth is in excess of 300 km/sec, and the average proton temperature is of the order of 10,000 °K. Both of these figures are higher than those obtained by the 2-fluid hydrodynamical model. The velocity far from the base of the model varies as Te1/2 and is relatively insensitive to temperature or velocity at the base or to the location of the base. The thermal anisotropy of the protons, T∥/T⊥, is predicted to be about 50.