Analysis of new WHT, VLT, and SOAR observations: Confirming new galaxy clusters from Planck & Calibrating the masses of high-redshift SPT clusters via weak gravitational lensing for cosmological investigations

我们请求DFG资助对针对大规模高红移星系团和候选星系团的新观测数据进行科学分析。这些观测结果是申请人作为主要研究者通过在主要天文学设施上进行望远镜开放时间的竞争性国际呼吁获得的。我们将利用WHT观测结果来确认普朗克Sunyaev-Zel'dovich（SZ）巡天中新的候选星系团，并测量它们的红移和丰富度。我们新的VLT和SOAR观测结果，以及补充的HST数据，目标是来自南极望远镜（SPT）SZ巡天的大质量高红移星系团。对这些观测结果的分析将使我们能够通过测量弱引力透镜（WL）图像失真来经验地校准大质量遥远星系团的质量尺度。当背景星系的光束通过星系团的引力势时，这些畸变会印在背景星系的形状上。我们的分析将产生目前最紧密的星系团质量校准在红移z~0.9处，以及第一个z>1.2的SZ星系团质量校准。这些约束将提供缺失的部分，使我们能够同时改善SPT星系团样本的暗能量约束和我们对大质量高红移星系团天体物理学的理解。

We request DFG funding to conduct the scientific analysis of new observational data targeting massive high-redshift galaxy clusters and cluster candidates. These observations were obtained by the applicant as Principal Investigator via competitive international calls for open telescope time on major astronomical facilities. We will use our WHT observations to confirm new cluster candidates from the Planck Sunyaev-Zel’dovich (SZ) survey and to measure their redshift and richness.Our new VLT and SOAR observations, as well as complementary HST data, target massive high-redshift galaxy clusters from the South Pole Telescope (SPT) SZ survey. The analysis of these observations will allow us to calibrate the mass scale of massive distant clusters empirically via the measurement of weak gravitational lensing (WL) image distortions. These distortions are imprinted onto the shapes of background galaxies when their light bundles pass through the gravitational potential of the clusters.Our analysis will yield the tightest currently available cluster mass calibration at redshift z~0.9, and the first mass calibration for SZ clusters at z>1.2. These constraints will provide the missing piece that will allow us to simultaneously improve dark energy constraints from the SPT cluster sample and our understanding of the astrophysics of massive high-redshift galaxy clusters.