Flux Ratios as a Probe of Dark Substructures in Quadruple-Image Gravitational Lenses
Flux Ratios as a Probe of Dark Substructures in Quadruple-Image Gravitational Lenses
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DOI：
10.1086/339798
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发表时间：
2001-11
期刊：
影响因子：
--
通讯作者：
R. Metcalf;HongSheng Zhao
中科院分区：
文献类型：
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作者：
R. Metcalf;HongSheng Zhao
我们证明，四像透镜类星体的通量比提供了探测暗物质晕小尺度结构的有力手段。一系列平滑透镜模型可以仅使用图像和透镜的位置作为输入来精确预测通量比的某些组合。使用五个观察到的透镜系统，我们表明真实的星系不能用光滑的奇异等温椭球体来描述，也不能用更一般的椭圆幂律势来描述。尚不能排除椭圆模型造成的大规模扭曲。然而，通过与模拟进行比较，我们发现这些数据可以由在距离透镜中心几千秒差距的投影距离内大量（≳5%）的暗子结构来解释。这种解释有利于冷暗物质模型而不是暖暗物质模型或自相互作用暗物质模型。
We demonstrate that the flux ratios of quadruple-image lensed quasars provide a powerful means of probing the small-scale structure of dark matter halos. A family of smooth lens models can precisely predict certain combinations of flux ratios using only the positions of the images and the lens as inputs. Using five observed lens systems, we show that real galaxies cannot be described by smooth singular isothermal ellipsoids, nor by the more general elliptical power-law potentials. Large-scale distortions from the elliptical models cannot yet be ruled out. Nevertheless, we find by comparing with simulations that the data can be accounted for by a significant (≳5%) amount of dark substructures within a projected distance of several kiloparsecs from the center of the lenses. This interpretation favors the cold dark matter model over the warm or self-interacting dark matter models.