Multidimensional nature of core-collapse supernova leads to asymmetric matter ejection and neutrino emission, that potentially accounts for the origin of neutron star (NS) kick. Asymmetric neutrino radiation fields are, in general, accompanied by large-scale inhomogeneous fluid distributions, in particular for electron-fraction ($Y_e$) distributions. Recently, it has also been revealed that lower $Y_e$ environments in proto-neutron star envelope can offer preferable conditions for collective neutrino oscillations. In this paper, we show that a dipole asymmetry of fast neutrino-flavor conversion (FFC), one of the collective neutrino oscillation modes, can power a NS kick, and that it would generate a characteristic correlation between asymmetric distributions of heavy elements in the ejecta and the direction of NS kick. We strengthen our argument for the FFC-driven NS kick mechanism by performing axisymmetric neutrino transport simulations with full Boltzmann neutrino transport. We show that this mechanism can generate linear momentum of neutrinos to account for typical proper motions of NS. Although more detailed studies are necessary, the present study opens a new channel to give a natal NS kick.

中文翻译：

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由不对称快中微子味道转换驱动的中子星反冲

核心塌陷超新星的多维性质导致不对称物质喷射和中微子发射，这可能解释中子星（NS）踢的起源。不对称中微子辐射场通常伴随着大范围的不均匀流体分布，特别是电子分数（${是}_e$）分布。近日，还有消息称，降低${是}_e$原中子星包层中的环境可以为集体中微子振荡提供更好的条件。在本文中，我们证明了快速中微子味道转换（FFC）（集体中微子振荡模式之一）的偶极不对称性可以为 NS 冲击提供动力，并且它将在中微子中重元素的不对称分布之间产生特征相关性。喷射物和 NS 踢的方向。我们通过使用完整的玻尔兹曼中微子输运进行轴对称中微子输运模拟，强化了对 FFC 驱动的 NS 反冲机制的论证。我们证明，这种机制可以产生中微子的线性动量，以解释中微子的典型自行运动。尽管需要进行更详细的研究，但本研究开辟了一条新的途径来促进出生性 NS 的发挥。