论文标题
伴侣镜头星系在类重力镜头B1152+199中的作用
Role of the companion lensing galaxy in the CLASS gravitational lens B1152+199
论文作者
论文摘要
我们使用存档的哈勃太空望远镜（HST）数据和非常长的基线干涉法（VLBI）数据来重新评估宇宙镜头全天际调查（类）重力透镜B1152+199。从HST Tri频段图像测量了宿主星系和X-Galaxy之间有效半径内的一致光度比，这将导致两个星系之间的质量比为$ R_B \ sim 2 $。为了确定X-galaxy在镜头系统中的作用，我们对双镜头系统建模，并从VLBI固定的喷气组件和HST图像中进行了约束。 8.4-GHz全球VLBI数据当前为质量模型提供了最严格的约束，尤其是对径向幂律斜率。这两个图像三组分的无线电镜头的优化模型偏向于陡峭的内部斜率。还研究了图像B中的喷射弯曲，事实证明这是一种未对准而不是曲率。拟合的优点表明，如果要拟合三对分辨的喷气组件，则X-Galaxy在镜头系统中的作用至关重要。当我们使用HST Tri-Band数据将最佳模型从无线电约束到光学建模时，优化保持了最佳模型的一致性，并成功地重现了HST图像中观察到的功能。这意味着在HST图像中发现的扩散发射实际上是对伴侣镜头的次级透镜效应的检测。
We reinvestigate the Cosmic Lens All-Sky Survey (CLASS) gravitational lens B1152+199 using archived Hubble Space Telescope (HST) data and Very Long Baseline Interferometry (VLBI) data. A consistent luminosity ratio within effective radius between the host galaxy and the X-galaxy is measured from HST tri-band images, which leads to a mass ratio between the two galaxies as $r_b\sim 2$. To determine the role of the X-galaxy in the lens system, we modelled the dual-lens system with constraints from the VLBI-resolved jet components and the HST images. The 8.4-GHz global-VLBI data currently provide the most stringent constraints to the mass model, especially to the radial power-law slope. The optimized models for this two-image three-component radio lens favour a steeper-than-isothermal inner slope. The jet bending in image B was also investigated and it turned out to be rather a misalignment than a curvature. The goodness of fit indicates that the role of the X-galaxy is crucial in the lens system if three pairs of resolved jet components are to be fitted. When we imported the optimal model from radio constraints to optical modelling with the HST tri-band data, the optimization kept the consistency of the optimal model and successfully reproduced the features observed in the HST images. This implies that the diffuse emission discovered in the HST images is actually a detection of the secondary lensing effects from the companion lens.
