论文标题
粒子自旋对轨迹挠度和重力镜头的影响
Effect of Particle Spin on Trajectory Deflection and Gravitational Lensing
论文作者
论文摘要
测试粒子的自旋是一种基本特性，可以影响其在重力场中的运动。在这项工作中，我们考虑了粒子自旋对任意固定和轴对称空间赤道平面中其挠度角和重力透镜的影响。为此，我们开发了一种扰动方法，该方法可以应用于任意渐近速度的旋转信号，并考虑到源和观察者的有限距离效应。挠度角$Δφ$和总行程$ΔT$表示为（Quasi）功率序列，其系数是度量函数的渐近扩展系数的多项式。发现自旋和轨道角动量平行（或反平行）时，偏转角会降低（或增加）。明显的角度$θ$在重力镜头中的图像及其时间延迟也得到了解决。在Kerr Spacetime中，自旋影响明显的角度$θ_K$，类似于其对$Δφ_K$的影响。发现相反旋转的信号之间的时间延迟与领先顺序的信号旋转成正比。这些时间延迟可用于约束中微子的自旋质量比。
Spin of a test particle is a fundamental property that can affect its motion in a gravitational field. In this work we consider the effect of particle spin on its deflection angle and gravitational lensing in the equatorial plane of arbitrary stationary and axisymmetric spacetimes. To do this we developed a perturbative method that can be applied to spinning signals with arbitrary asymptotic velocity and takes into account the finite distance effect of the source and the observer. The deflection angle $Δφ$ and total travel time $Δt$ are expressed as (quasi-)power series whose coefficients are polynomials of the asymptotic expansion coefficients of the metric functions. It is found that when the spin and orbital angular momenta are parallel (or antiparallel), the deflection angle is decreased (or increased). Apparent angles $θ$ of the images in gravitational lensing and their time delays are also solved. In Kerr spacetime, spin affects the apparent angle $θ_K$ in a way similar to its effect on $Δφ_K$. The time delay between signals with opposite spins is found to be proportional to the signal spin at leading order. These time delays might be used to constrain the spin to mass ratio of neutrinos.
