Toward an Accurate Model for the Gas Around Galaxies

California Institute Of Technology, Pasadena CA

Investigators

Abstract

Observations of nearby galaxies show that these galaxies are still growing, as gas clouds surrounding them fall into these galaxies. So far, models of how galaxies grow, and stars form, do not fully explain the observations. The investigators will more finely model the physical properties of the infalling gas. The investigators have strongly argued that better numerical models will explain the discrepancies. The circumgalactic medium (CGM), the low-density gas surrounding galaxies, is increasingly recognized for its crucial role in the complicated process of forming new generations of stars in galaxies. Observations of the CGM indicate large quantities gas are present around galaxies. However, theorists cannot explain why that gas exists in such large abundances, because current computer models severely underpredict it. Recent discoveries indicate that traditional simulations fail to resolve small cool gas clouds, potentially explaining the mismatch between theory and observation. The investigators are now running state-of-the-art simulations which track the cool gas component explicitly. In this study, they will make novel comparisons between our simulations and many observations of the CGM. The investigators will use the observations to deduce how accurate their models are at explaining the elusive behavior of the CGM and its effects on galaxy growth. Traditionally, public education efforts held in scientific institutions bias target audiences towards people already excited about science, while ignoring much of the rest of the community. The investigator's team organizes public education activities in non-traditional venues like parks, pedestrian streets, public transportation, bars, etc. to truly reach a wide cross-section of our society, including underrepresented groups in STEM. The investigators will extend existing outreach efforts by designing and building an "AstroViz" kit, capable of projecting state-of-the-art computational simulations at these non-traditional public education events. These projections will employ the advanced visualizations that enable the public to quickly grasp concepts not easily conveyed through words alone. Applied to a nearby sidewalk or storefront, the investigators projected visualizations will better draw the attention of the public. 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.