论文标题
晚期快速中微子风味转换
Fast Neutrino Flavor Conversion at Late Time
论文作者
论文摘要
我们研究中微子在1+1维中的完全非线性快速风味演变。我们的数值分析表明，在很晚，该系统达到了大致稳定状态。使用稳态近似，我们分析表明，极化向量的空间变化是由它们围绕公共轴的进动给出的，该轴本身具有让人联想到陀螺摆阴茎的运动。然后，我们表明，运动方程的稳态解决方案不能以位置和速度分离，那就是运动在通常的意义上不是集体的。但是，快速演化允许光谱 - 不同的动力学，从而导致一系列速度的部分脱干，并受Lepton数量的保护约束。最后，我们从数值上表明，在最晚，极化矢量的横向成分在任何速度模式和Lepton不对称方面都在不同的空间位置随机定向。
We study the fully nonlinear fast flavor evolution of neutrinos in 1+1 dimensions. Our numerical analysis shows that at late time the system reaches an approximately steady state. Using the steady state approximation we analytically show that the spatial variation of the polarization vectors is given by their precession around a common axis, which itself has a motion reminiscent of a gyroscopic pendulum. We then show that the steady state solution to the equations of motion cannot be separated in position and velocity, that is the motion is not collective in the usual sense. However, the fast evolution allows spectral-swap-like dynamics leading to partial decoherence over a range of velocities, constrained by conservation of lepton number(s). Finally, we numerically show that at late time the transverse components of the polarization vectors become randomly oriented at different spatial locations for any velocity mode and lepton asymmetry.
