论文标题
渐近循环重力镜片的四倍图像配置
The Quadruple Image Configurations of Asymptotically Circular Gravitational Lenses
论文作者
论文摘要
检查了具有消失椭圆度的重力镜片的四倍图像配置。即使这种镜头渐近接近圆形，如果源相对于消失的钻石苛性碱的位置保持恒定，则构型稳定。配置是四分之一方程的解，即“渐近圆形镜头方程”（ACLE），由单个复杂数量进行参数化。检查了几种替代参数化。图像的相对宏伟被得出。当以外部剪切（Xs）的形式添加到奇异等温球（SIS）的非呈刺激四极形式时，其构型自然会随着圆形配置的拉伸和挤压版本而自然出现。而且，由于SIS+XS模型是大多数四倍镜头类星体的良好的第一个近似值，因此它们的配置同样只有2+1个明显的尺寸。渐近的圆形配置可以轻松地适应太阳系“掩盖闪烁”的问题。
The quadruple image configurations of gravitational lenses with vanishing ellipticity are examined. Even though such lenses asymptotically approach circularity, the configurations are stable if the position of the source relative to the vanishing diamond caustic is held constant. The configurations are the solutions of a quartic equation, an "Asymptotically Circular Lens Equation" (ACLE), parameterized by a single complex quantity. Several alternative parameterizations are examined. Relative magnifications of the images are derived. When a non-vanishing quadrupole, in the form of an external shear (XS), is added to the singular isothermal sphere (SIS), its configurations emerge naturally as stretched and squeezed versions of the circular configurations. And as the SIS+XS model is a good first approximation for most quadruply lensed quasars, their configurations likewise have only 2+1 salient dimensions. The asymptotically circular configurations can easily be adapted to the problem of Solar System "occultation flashes."
