Improved mass constraints for two nearby strong-lensing elliptical galaxies from Hubble Space Telescope imaging
Improved mass constraints for two nearby strong-lensing elliptical galaxies from Hubble Space Telescope imaging
复制标题
改进了哈勃太空望远镜成像中两个附近强透镜椭圆星系的质量约束
DOI：
10.1093/mnras/stx2297
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发表时间：
2018
影响因子：
4.8
通讯作者：
Collier W
中科院分区：
文献类型：
--
作者：
Collier W
本文分析了哈勃望远镜新获得的两个强透镜椭圆星系SNL-1 （z= 0.03）和SNL-2 （z= 0.05）的图像，以改善透镜质量约束。成像显示了透镜星系和透镜图像中以前看不见的结构。对于具有良好分辨源的SNL-1，我们利用相对放大信息打破了质量-剪切简并，测量到透镜质量为9.49±0.15 × 1010M⊙，比之前的估计增加了7%。对于SNL-2，成像显示了一个明亮的未解析源成分，由于可能的活动星系核微透镜或变异性，这提出了额外的复杂性。我们暂时使用相对放大信息来限制SNL-2附近伴星星系的贡献，测量到的透镜质量为12.59±0.30 × 1010M⊙，质量增加了9%。我们改进的透镜模型将质量不确定性分别从5%和10%降低到2%和3%。我们的研究结果支持了之前的分析结论，SNL-1和SNL-2相对于银河系（Kroupa）初始质量函数的质量过剩参数分别为1.17±0.09和0.96±0.10。
We analyse newly obtainedHubble Space Telescopeimaging for two nearby strong lensing elliptical galaxies, SNL-1 (z= 0.03) and SNL-2 (z= 0.05), in order to improve the lensing mass constraints. The imaging reveals previously unseen structure in both the lens galaxies and lensed images. For SNL-1, which has a well resolved source, we break the mass-versus-shear degeneracy using the relative magnification information, and measure a lensing mass of 9.49 ± 0.15 × 1010M⊙, a 7 per cent increase on the previous estimate. For SNL-2, the imaging reveals a bright unresolved component to the source and this presents additional complexity due to possible active galactic nucleus microlensing or variability. We tentatively use the relative magnification information to constrain the contribution from SNL-2's nearby companion galaxy, measuring a lensing mass of 12.59 ± 0.30 × 1010M⊙, a 9 per cent increase in mass. Our improved lens modelling reduces the mass uncertainty from 5 and 10 per cent to 2 and 3 per cent, respectively. Our results support the conclusions of the previous analysis, with newly measured mass excess parameters of 1.17 ± 0.09 and 0.96 ± 0.10 for SNL-1 and SNL-2, relative to a Milky Way like (Kroupa) initial mass function.
影响因子：
8.7
作者：
Komatsu, E.;Smith, K. M.;Wright, E. L.
通讯作者：
Wright, E. L.