16892

We propose VLA A-config Ku- and C-band imaging to resolve the sub-arcsec double nuclei in 11 candidate dual- lensed quasars. Our targets are selected using a new astrometric technique leveraging the universal AGN variability which produces astrometric signals from dual-lensed quasars. Gaia.s precision astrometry combined with follow- up HST optical dual-band imaging provides strong candidates of dual-lensed quasars with close compact double cores. We adopt a refined target selection based on the HST optical color to better reject star-quasar superpositions compared to a pilot program. The proposed VLA dual-band imaging will detect two compact flat-spectrum radio cores to confirm our targets as dual or lensed quasars. Joint HST-IR imaging is requested to further test the lensing scenario to identify bona-fide dual quasars. Our sample probes a new regime at higher redshifts and smaller merger separations than previous work comma where mergers are thought to be more important in driving the evolution of galaxies and supermassive black holes comma providing empirical constraints on the stochastic gravitational wave background from binary supermassive black holes.

我们提出采用甚大阵（VLA）A配置的Ku波段与C波段成像技术，以解析11个候选双透镜类星体中的亚角秒级双核结构。我们的目标源通过一种新的天体测量技术筛选而来，该技术利用了活动星系核（AGN）的普遍变异性——这种变异性会从双透镜类星体中产生天体测量信号。盖亚（Gaia）的高精度天体测量数据与后续哈勃空间望远镜（HST）的光学双波段成像相结合，为具有紧密致密双核结构的双透镜类星体提供了强有力的候选样本。与试点项目相比，我们基于哈勃空间望远镜（HST）光学颜色采用了优化的目标源筛选方法，以更有效地排除恒星-类星体叠加的情况。拟议的甚大阵（VLA）双波段成像将探测到两个致密的平谱射电核，从而确认我们的目标源是否为双透镜类星体。我们还申请联合哈勃空间望远镜红外成像以进一步验证透镜场景，从而识别真实的双类星体。我们的样本探索了一个新的研究领域——与以往工作相比，其红移更高且并合间距更小；在此领域中，并合被认为在驱动星系和超大质量黑洞演化方面更为重要，这将为双超大质量黑洞产生的随机引力波背景提供经验约束。