0 Assigned ID: 4727 ----- Attempting Submission 1 (Wed May 24 22:19:12 GMT 2023) ----- The evolution of galaxies is driven by the flow of gas into and out of them, but how this process is connected to the diffuse gas in the large-scale cosmic web is poorly understood. QSO absorption lines can probe the gas in both the local and global surroundings of galaxies. We propose to leverage >770 archival QSO spectra observed with HST/COS to probe the filamentary gas in the cosmic web and study its impact on galaxy evolution. We will utilize 3D cosmic matter density fields reconstructed by the novel slime mold-inspired Monte Carlo Physarum Machine (MCPM) model using >600,000 SDSS DR17 galaxies at z<=0.5. These density fields will be fed into the DisPerSE cosmic web framework to extract the most detailed filament catalogs of the observed low-redshift universe to date. Using HST/COS QSO lines-of-sight, we will probe gas in different cosmic web environments characterized by matter density and distance to nearest filament, from dense filament cores to outskirts to voids. We will stack the spectra to measure average absorption signal in HI Lya and metals with respect to the cosmic web environment. We will also identify individual HI absorbers and measure their absorption strengths (equivalent width) and kinematics (velocity width) as functions of the cosmic environment. We aim to quantify the relationship between gas absorption strength and kinematics with specific star formation rate and gas mass of nearby galaxies in different cosmic environments. The key goals of our analysis are to 1) measure the change in gas properties from dense to diffuse cosmic environments, and 2) understand how these gas properties impact the gas flows onto galaxies at much smaller scales. Mr. Farhanul Hasan (PI) is a rising sixth year graduate student with extensive experience with QSO absorption line identification spectroscopy, having performed detection and analysis of absorption systems. He is also very experienced with cosmic web structure identification, large-scale cosmological simulations, and observational galaxy surveys. He will be the most involved in carrying out the analysis in this project, including obtaining and collating all the necessary observed data and performing analysis of simulation data. He will lead the papers mentioned in this proposal. Prof. Joe Burchett is an expert at QSO absorption line studies, their connection with galaxies, and large-scale cosmic web structure. His experience includes spectral analysis, measurement of absorption properties, and Cloudy ionization modeling. He will be engaged in mentoring, data analysis at every step of the project, high level science discussions, and paper writing. Dr. Oskar Elek is an expert at computational media and data analytics and is the primary developer of the MCPM algorithm described in this proposal. He will be involved with refining the MCPM algorithm and the data analysis workflow. Prof. Rongmon Bordoloi is an expert in observational QSO absorption line studies and the connection between absorbers and galaxies. His main involvement will be in the analysis of the spectra, including absortption line detection. He will be involved in high-level science discussions, mentoring, and paper writing. Dr. Douglas Hellinger is an expert in cosmological simulations and computational media. He will be primarily involved in developing the data analysis pipeline for the first part of this project, as well as assist in analysis of the simulations. Large Scale Structure of the Universe Intergalactic Medium and the Circumgalactic Medium 0 Regular false false false false false false SUPPORTED