我们提出了一个特殊的系统SDSS J1538+5817的透镜和测光研究,确定的SLACS调查。透镜是一个明亮的椭圆,红移z=0.143。使用两种不同的过滤器中的HST公共图像,两个背景源透镜到爱因斯坦环和双系统的存在被确定。我们在NOT进行的新光谱观测表明,这两个源位于相同的红移z=0.531。我们调查的总质量分布的透镜之间的1和4千秒差距的星系中心的参数和非参数透镜编码,描述的多个图像的点状物体。几种不同的透镜模型一致认为:(1)精确地再现了观察到的图像位置;(2)预测了一个接近轴对称的总质量分布,其中心和方向与光分布相同;(3)测量出在2.5 kpc的爱因斯坦半径内投影的总质量的值为8.11 x 10^{10} M_{Sun};(4)估计总质量密度分布比等温分布稍陡。将SDSS测光与CSP模型进行拟合,得出星系的恒星总质量为20 x 10^{10} M_{Sun},爱因斯坦半径内的总质量中投射光的比例为0.9。通过结合透镜和光度质量测量,我们区分透镜的质量含量的发光和暗物质组件。这种双组分模型,这是可行的,只有在特殊的系统,如SDSS J1538+5817,导致描述的星系暗物质晕的全球性质。将这些结果推广到更大数量的透镜将大大提高我们对LCDM情景中星系形成和演化过程的理解。
英文摘要:
We present a lensing and photometric study of the exceptional system SDSS J1538+5817, identified by the SLACS survey. The lens is a luminous elliptical at redshift z=0.143. Using HST public images in two different filters, the presence of two background sources lensed into an Einstein ring and a double system is ascertained. Our new spectroscopic observations, performed at the NOT, reveal that the two sources are located at the same redshift z=0.531. We investigate the total mass distribution of the lens between 1 and 4 kpc from the galaxy center by means of parametric and non-parametric lensing codes that describe the multiple images as point-like objects. Several disparate lensing models agree on: (1) reproducing accurately the observed image positions; (2) predicting a nearly axisymmetric total mass distribution, centered and oriented as the light distribution; (3) measuring a value of 8.11 x 10^{10} M_{Sun} for the total mass projected within the Einstein radius of 2.5 kpc; (4) estimating a total mass density profile slightly steeper than an isothermal one. A fit of the SDSS multicolor photometry with CSP models provides a value of 20 x 10^{10} M_{Sun} for the total stellar mass of the galaxy and of 0.9 for the fraction of projected luminous over total mass enclosed inside the Einstein radius. By combining lensing and photometric mass measurements, we differentiate the lens mass content in terms of luminous and dark matter components. This two-component modeling, which is viable only in extraordinary systems like SDSS J1538+5817, leads to a description of the global properties of the galaxy dark matter halo. Extending these results to a larger number of lenses would improve considerably our understanding of galaxy formation and evolution processes in the LCDM scenario.
Mind the Information Gap: Unveiling Detailed Morphologies of z 0.5-1.0 Galaxies with SLACS Strong Lenses and Data-Driven Analysis
Ciela - Montreal Institute for Astrophysical Data Analysis and Machine Learning(Ciela - 蒙特利尔天体物理数据分析与机器学习研究所);Mila - Quebec Artificial Intelligence Institute(Mila - 魁北克人工智能研究所);University of Edinburgh(爱丁堡大学);Center for Computational Astrophysics, Flatiron Institute(平顿研究所计算天体物理学中心);Trottier Space Institute(特罗蒂尔空间研究所);Perimeter Institute(珀imeter研究所)
SDSS-IV MaNGA: A Catalogue of Spectroscopically Detected Strong Galaxy-Galaxy Lens Candidates
我们在光谱上探测到了8条可能的候选发射线,17条可能的候选发射线,以及69条可能的强星系-星系引力透镜候选发射线,这些候选发射线是在Apache Point Observatory(MaNGA)完成的邻近星系测绘中包含的约10,000个星系目标的光谱中发现的。这种搜索是基于透镜物体(SILO)项目的光谱识别方法,该项目扩展了BOSS发射线透镜调查(BELLS)和斯隆透镜ACS调查(SLACS)的光谱检测方法。我们扫描了我们从前景减去行堆叠光谱(RSS)的堆栈中构建的共同添加的残差,因此可以使用sigma-clipping方法来拒绝宇宙射线和其他形式的瞬变,这些瞬变仅影响组合曝光的一小部分。我们还构建了窄带图像的信噪比的共同添加的残差观察透镜源图像的迹象。我们还使用了几种方法来计算可能的强透镜制度,每个候选透镜,以确定候选背景星系可能居住在足够靠近星系中心的强透镜发生。我们提出的光谱红移的增值目录(VAC)的数据发布17(DR 17)的SDSS-IV。我们还介绍了镜头候选人,光谱数据,并在VAC的DR 17窄带图像。这些透镜候选者的高分辨率后续成像预计将产生确认的A级透镜的样本,具有足够的角尺寸,以探测来自最佳拟合透镜模型的质量与来自观测到的恒星速度的动态质量之间可能存在的差异。
Line-of-sight shear in SLACS strong lenses I: shear and mass model parametrisations
Institute of Astronomy, University of Cambridge(剑桥大学天文学研究所);Kavli Institute for Cosmology, University of Cambridge(剑桥大学卡弗里宇宙学研究所);Clare Hall(克莱尔学院);Laboratoire Univers et Particules de Montpellier, CNRS & Université de Montpellier(蒙彼利埃大学与法国国家科学研究中心宇宙与粒子物理实验室);Department of Astronomy & Astrophysics, University of Chicago(芝加哥大学天文与天体物理系);Kavli Institute for Cosmological Physics, University of Chicago(芝加哥大学卡弗里宇宙物理学研究所);Center for Astronomy, Space Science and Astrophysics, Independent University, Bangladesh(孟加拉独立大学天文、空间科学与天体物理中心)
Probing sub-galactic mass structure with the power spectrum of surface-brightness anomalies in high-resolution observations of galaxy-galaxy strong gravitational lenses. I. Power-spectrum measurement and feasibility study