Collaborative Research: The Effect of Filaments on the Gas in Galaxies

University Of Kansas Center For Research Inc, Lawrence KS

Investigators

Abstract

Astronomers seek to understand how galaxies form and evolve. A galaxy's growth may be affected by processes within the galaxy itself and/or by its environment. Such growth is measured by the rate of new star formation. Galaxies can be found among vast aggregates of matter which are called filaments; alternatively, they may be isolated from one another. Galaxies found in filaments typically grow more slowly than isolated galaxies. Finn and collaborators seek to understand why filaments quench star formation. This project will combine imaging of the gas that fuels star formation in galaxies with observations that reveal the resulting star formation. Investigators will compare galaxies in both types of environment to determine the method of star formation quenching. Their results will challenge theoretical models. The project will also continue a successful, ongoing outreach to a local high school. Peer instruction will be added to leverage impact without additional funds. Kansas, the state where one of the investigators is located, is on the front-lines of the nationwide debate on the role of science in the classroom. Therefore, this effort to broaden participation in science is especially timely and relevant. This project will combine a large imaging survey in H-alpha and observations of neutral Hydrogen (HI) and molecular gas (CO). The project has three specific aims. The first aim is to directly measure whether the amount of neutral and/or molecular gas available to eventually form stars is measurably lower in filament galaxies compared to those in the field, group, or cluster environment. The second aim focuses on the spatial distribution of star formation within each galaxy. This aim will determine whether ram pressure stripping, starvation, and/or mergers are significant mechanisms for quenching star formation. The third aim uses the results of the first two aims to confront theoretical models of star formation quenching in the context of cosmological structure growth. The Data Management Plan includes release of the main data products: H-alpha + continuum maps of 200 galaxies and HI and CO measurements. Ancillary and raw data will be released upon publication and archived.