Models of the Giant Quadruple Quasar SDSS J1004+4112
Models of the Giant Quadruple Quasar SDSS J1004+4112
复制标题
巨型四类星体 SDSS J1004 4112 的模型
DOI：
10.1086/426007
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
P. Saha
中科院分区：
文献类型：
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作者：
L. Williams;P. Saha
SDSS J1004+4112是一个前所未有的物体。它看起来很像几个被各个星系透镜化的四重类星体，只不过它大了约 10 倍，而且透镜是一个以暗物质为主的星团。我们使用最近开发的方法对晶状体进行自由形式重建。投影的星团质量分布与浅层 r-0.3 至 r-0.5 一致，并且可以拟合 Navarro-Frenk-White 或平核三维质量分布。然而，我们不能排除预测剖面陡峭至 r-1.3 的可能性。 100 kpc 内的投影质量被很好地限制为 (5 ± 1) × 1013 M⊙，与以前的更简单的模型一致。然而，与之前的工作不同的是，我们能够检测透镜中与星团星系相关的结构。我们估计了与这些星系相关的质量，并表明它们在 100 kpc 范围内贡献的质量不超过星团总质量的 10%。典型的星系质量与典型的光度相结合，可以粗略估计其质量与光的比率，该比率为个位数。最后，我们讨论了该系统中时滞测量的含义，以及部分爱因斯坦环的可能性。
SDSS J1004+4112 is an unprecedented object. It looks much like several quadruple quasars lensed by individual galaxies, only it is ∼10 times larger and the lens is a cluster dominated by dark matter. We present free-form reconstructions of the lens using recently developed methods. The projected cluster mass profile is consistent with being shallow, r-0.3 to r-0.5, and can be fitted with either a Navarro-Frenk-White or a flat-cored three-dimensional mass distribution. However, we cannot rule out projected profiles as steep as r-1.3. The projected mass within 100 kpc is well constrained as (5 ± 1) × 1013 M⊙, consistent with previous simpler models. Unlike previous work, however, we are able to detect structures in the lens associated with cluster galaxies. We estimate the mass associated with these galaxies and show that they contribute not more than about 10% of the total cluster mass within 100 kpc. Typical galaxy masses, combined with typical luminosities, yield a rough estimate of their mass-to-light ratio, which is in the single digits. Finally, we discuss implications for time-delay measurements in this system, and possibilities for a partial Einstein ring.