We consider the specific case of disc accretion for negligibly low viscosity and infinitely high electric conductivity. The key component in this model is the outflowing magnetized wind from the accretion disc, since this wind effectively carries away angular momentum of the accreting matter. Assuming magnetic field has variable polarity in the disc (to avoid magnetic flux and energy accumulation at the gravitational center), this leads to radiatively inefficient accretion of the disc matter onto the gravitational center. In such a case, the wind forms an outflow, which carries away all the energy and angular momentum of the accreted matter. Interestingly, in this framework, the basic properties of the outflow (as well as angular momentum and energy flux per particle in the outflow) do not depend on the structure of accretion disc. The self-similar solutions obtained prove the existence of such an accreting regime. In the self-similar case, the disc accretion rate (M ) depends on the distance to the gravitational center, r, as M r 1 2(λ2-1), where λ is the dimensionless Alfvenic radius. Thus, the outflow predominantly occurs from the very central part of the disc provided that λ 1 (it follows from the conservation of matter). The accretion/outflow mechanism provides transformation of the gravitational energy from the accreted matter into the energy of the outflowing wind with efficiency close to 100%. The flow velocity can essentially exceed the Kepler velocity at the site of the wind launch.
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机译：我们考虑圆盘附着的特殊情况，因为其低粘度和无限高的电导率。该模型的关键部分是从吸积盘流出的磁化风，因为这种风有效地带走了吸积物的角动量。假设磁场在圆盘中具有可变的极性（以避免磁通量和能量在重力中心处积聚），这会导致圆盘物质以辐射方式效率低下地积聚到重力中心上。在这种情况下，风形成流出物，带走了积垢物的所有能量和角动量。有趣的是，在此框架中，流出物的基本属性（以及流出物中每个粒子的角动量和能量通量）不取决于吸积盘的结构。获得的自相似解证明了这种吸积机制的存在。在自相似情况下，圆盘吸积率（M）取决于距重心r的距离，即M r 1 2（λ2-1），其中λ是无量纲的Alfvenic半径。因此，只要λ1（它来自物质守恒），流出主要发生在圆盘的最中央部分。吸积/流出机制将重力能量从吸积物质转换为流出风能，效率接近100％。流速可以基本上超过风力发射场的开普勒速度。
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