Collaborative Research: Exploring reionization and the cosmic dawn through cross-correlations

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

Over the next several years, new astronomical observatories are poised to revolutionize our understanding of the earliest generations of galaxies to form in our Universe. The James Webb Space Telescope will provide an unprecedented census of these galaxies, while instruments such as the Simons Observatory and Hydrogen Epoch of Reionization Array will explore their impact on the surrounding Universe. However, maximizing the science return of these telescopes requires sophisticated modeling of this first generation of galaxies. This project is a collaboration between scientists at the University of Nevada, the University of California, Los Angeles, and Arizona State University, to develop a suite of flexible, powerful models for interpreting the up-coming observations from these powerful telescopes. As a part of this project, the team will also focus on providing research training for undergraduate students from underrepresented groups, and thus help diversify the next generation of astronomy researchers. In addition, the team will develop online teaching materials to engage children in the scientific process. This project has three principal aims. First, the proposing team will develop a series of new galaxy modeling tools to improve semi-numeric simulations of the Epoch of Reionization. Beginning with their existing analytic models of these galaxies, the team will add prescriptions for Lyman-alpha emission lines, which will then be combined with large-volume numerical simulations of the galaxy field. The team will use these models to study how reionization impacts the Lyman-alpha lines, not only in an average sense but also when applied to specific galaxy populations. Second, this project will develop tools for "cross-comparisons" between data sets. The goal is to explore how galaxy surveys can measure the large-scale density and ionization fields to inform measurements of the intergalactic medium, and the team will examine how low-frequency radio measurements can identify ionized regions to inform galaxy measurements. Finally, this project will forecast the results of cross-correlations between measurements of high-redshift galaxy surveys, the 21cm signal, line intensity mapping signals, and the cosmic microwave background. 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.