论文标题
碰撞引起的快速中微子风味转化的增强或阻尼
Enhancement or damping of fast neutrino flavor conversions due to collisions
论文作者
论文摘要
当非前瞻性碰撞也发挥作用时，核心溢出的超新星或紧凑的二进制合并残留物可能会发生快速中微子的风味转换，并且中微子并未完全与物质脱钩。这项工作旨在阐明碰撞增强或抑制快速风味转化的条件。在没有空间不均匀性的情况下，我们依靠具有三个角箱的中微子玩具模型，我们考虑了两种角构型：第一个具有$ν_e$和$ \ \barν_e$的角度分布几乎是完全消失的，在完全脱离和表现出很少的风味转换不足的风味对转换不足的情况下，它们几乎是等于预期的。第二个具有$ν_e$和$ \barν_e$的角度分布，它们在自由流动方面的预期达到峰值，并在没有碰撞的情况下显示出明显的风味转换。通过包括与角度无关的，方向变化的碰撞，我们发现碰撞是对前（后）角构型中风味转化的总体增强（阻尼）的原因。这些相反的结果是由于碰撞，风味转化和电子类中微子的初始角度分布之间的非平凡相互作用。在没有碰撞的情况下，发现中微子风味转化率的增强与风味转化的大小是反相关的。
Fast neutrino flavor conversion can occur in core-collapse supernovae or compact binary merger remnants when non-forward collisions are also at play, and neutrinos are not fully decoupled from matter. This work aims to shed light on the conditions under which fast flavor conversion is enhanced or suppressed by collisions. By relying on a neutrino toy model with three angular bins in the absence of spatial inhomogeneities, we consider two angular configurations: The first one with angular distributions of $ν_e$ and $\barν_e$ that are almost isotropic as expected before complete neutrino decoupling and showing little flavor conversion when collisions are absent. The second one with angular distributions of $ν_e$ and $\barν_e$ that are forward peaked as expected in the free-streaming regime and showing significant flavor conversion in the absence of collisions. By including angle-independent, direction-changing collisions, we find that collisions are responsible for an overall enhancement (damping) of flavor conversion in the former (latter) angular configuration. These opposite outcomes are due to the non-trivial interplay between collisions, flavor conversion, and the initial angular distributions of the electron type neutrinos. The enhancement in neutrino flavor conversion is found to be anticorrelated with the magnitude of flavor conversions in the absence of collisions.
