Sharpening our view of Cluster Cosmology

星系团是宇宙中物质分布的极好示踪者。已经投入大量资源来汇编星系团星表，因为这种调查可以用来得出重要的宇宙学参数。一种测量技术是使用Sunyaev-Zel‘dovich效应(SZE)，即星系团内的热气体扭曲了来自大爆炸的光的光谱。然而，来自单个星系和星系团合并的射电发射可能会使对SZE的解释复杂化，导致从星系团星表得出的宇宙学参数产生偏差的来源。在无线电频率上拍摄的高分辨率图像可以用来量化这些偏差。研究人员将使用绿岸望远镜(GBT)上的MUSTANG2相机绘制星系图。该计划的结果将有助于从过去、当前和未来的星系团调查投资中获得更准确的结果。在这项工作中，研究人员将维护MUSTANG2，确保更广泛的天文学社区仍然可以使用它。为了帮助培训更多样化的下一代STEM工人，该团队将与西蒙斯基金会和黑人物理学家协会合作，接待参与MUSTANG2项目的学生。通过参加弗吉尼亚大学举办的女孩探索宇宙(Getu)夏令营，计划扩大到中学生。此外，国际和平协会将继续在费城地区开展公众宣传活动。将首先调查重叠的ACT(阿塔卡马宇宙学望远镜)和eROSITA观测之间星团质量的大散射。该团队将(1)在SZE频率上完成对致密源的星系团的盲目调查(2)使用结果来校正观察样本的质量(3)建立源在不同类型星系团中的可能性的模型，该模型可用于在统计意义上校正质量-SZE关系以及(4)使用对选定星系团的更深层次的观测，在两次调查之间具有剩余质量差异的星系团来寻找原因。作为MUSTANG2维护的一部分，该团队将更好地将管道整合到天文台软件基础设施中，进一步促进天文学界使用MUSTANG2数据。这一奖励反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Clusters of galaxies are excellent tracers of the matter distribution in the Universe. Significant resources have been put into compiling cluster catalogs, because such surveys can be used to derive important cosmological parameters. One survey technique is to use the Sunyaev-Zel'dovich effect (SZE), which is when hot gas inside galaxy clusters distorts the spectrum of light from the Big Bang. However, radio emission from individual galaxies and cluster mergers can complicate interpretation of the SZE, resulting in sources of bias in cosmological parameters derived from cluster catalogs. High resolution images taken at radio frequencies can be used to quantify these biases. The investigators will use the MUSTANG2 camera on the Green Bank Telescope (GBT) to map clusters. Results from this program will help produce more accurate results from investments in past, current, and future galaxy cluster surveys. During this work, the investigators will maintain MUSTANG2, ensuring it remains available to the wider astronomical community. To help train a more diverse next generation of STEM workers, the team will work with the Simons Foundation and the Society of Black Physicists to host students working on MUSTANG2 projects. Outreach to middle school students is planned by participation in the Girls Exploring The Universe (GETU) summer camp run by the University of Virginia. In addition, the PI will continue public outreach activities in the Philadelphia area. The large scatter in cluster masses between the overlapping ACT (Atacama Cosmology Telescope) and eROSITA surveys will be investigated first. The team will (1) Finish a blind survey of clusters for compact sources at SZE frequencies (2) Use the results to correct the masses of the observed sample (3) Build a model for how likely sources are in different types of clusters that can be used to correct the mass-SZE relationship in a statistical sense and (4) Use deeper observations of selected clusters with remaining discrepant masses between surveys to find the cause. As part of the maintenance of MUSTANG2, the team will better integrate the pipeline into the observatory software infrastructure, further facilitating the use of MUSTANG2 data by the astronomical community.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.