An explanation for the large random velocities of pulsars is presented. Like many other models, we propose that the momentum imparted to the star is given at birth. The ultimate source of energy is provided by the intense optically thick neutrino flux that is responsible for radiating the proto-neutron star's gravitational binding energy during the Kelvin-Helmholtz phase. The central feature of the kick mechanism is a radiatively driven magnetoacoustic instability, which we refer to as "neutrino bubbles." Identical in nature to the photon bubble instability, the neutrino bubble instability requires the presence of an equilibrium radiative flux, as well as a coherent steady background magnetic field. Over regions of large magnetic flux densities, the neutrino bubble instability is allowed to grow on dynamical timescales ~1 ms, potentially leading to large luminosity enhancements and density fluctuations. Local luminosity enhancements, which preferentially occur over regions of strong magnetic field, lead to a net global asymmetry in the neutrino emission, and the young neutron star is propelled in the direction opposite to these regions. For favorable values of magnetic field structure, size, and strength, as well as neutrino bubble saturation amplitude, momentum kicks in excess of 1000 km s-1 can be achieved. Since the neutrino-powered kick is delivered over the duration of the Kelvin-Helmholtz time, a few seconds, one expects spin-kick alignment from this neutrino bubble-powered model.
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机译：给出了脉冲星大随机速度的解释。像许多其他模型一样，我们建议赋予恒星的动量是在出生时给出的。最终的能量来源是由强烈的光学厚度的中微子通量提供的，该通量在开尔文-亥姆霍兹相期间辐射了原中子星的引力结合能。脚踢机制的主要特征是辐射驱动的磁声不稳定性，我们将其称为“中微子气泡”。与光子气泡不稳定性本质上相同，中微子气泡不稳定性需要存在平衡的辐射通量以及相干的稳定背景磁场。在大磁通密度的区域上，中微子气泡的不稳定性会在约1 ms的动态时间尺度上增长，从而可能导致较大的光度增强和密度波动。局部发光度的增强（优先发生在强磁场的区域上）会导致中微子发射中的净全局不对称，并且年轻的中子星会朝与这些区域相反的方向推进。对于磁场结构，大小和强度以及中微子气泡饱和振幅的有利值，可以实现超过1000 km s-1的动量反冲。由于中微子驱动的踢球是在开尔文-亥姆霍兹时间（Kelvin-Helmholtz）的持续时间内（几秒钟）传递的，因此人们期望这种中微子气泡驱动的模型能够实现自旋踢对准。
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