0 Assigned ID: 1919 ----- Attempting Submission 1 (Fri Apr 09 14:00:12 GMT 2021) ----- HST Phase I Proposal 1919 successfully submitted. Receipt: # 1919-1 ----- Attempting Submission 2 (Fri Apr 09 17:19:03 GMT 2021) ----- HST Phase I Proposal 1919 successfully submitted. Receipt: # 1919-2 ----- Attempting Submission 3 (Fri Apr 09 17:45:28 GMT 2021) ----- HST Phase I Proposal 1919 successfully submitted. Receipt: # 1919-3 ----- Attempting Submission 4 (Fri Apr 09 21:46:28 GMT 2021) ----- Galactic outflows play a key role in the processes of galaxy formation and evolution. Using instruments like the Cosmic Origins Spectrograph aboard the Hubble Space Telescope, observers have spent thousands of hours gathering absorption spectra of outflows, hoping to determine how much mass, momentum, and energy galaxies eject. However, interpretation of these spectra is hampered by uncertainties related to the morphology and unknown physical state of the outflowing gas. Simulations of outflows offer a solution to this challenge, but their data must first be translated into observables - a non-trivial task, given the complicated ionization state modeling that must be done. In this proposal, we outline a plan to create open-source analysis software capable of post-processing data from almost any galaxy outflow simulation in order to produce mock spectra, which can be directly compared with observed HST/COS spectra from hundreds of sightlines. We will apply these new analysis tools to existing simulation datasets, in order to (1) determine which simulations produce outflows with physical properties that are consistent with observations; and (2) place tighter constraints on the derived physical properties of outflows from existing HST spectra. These synthetic spectra will comprise a new test to discriminate between different driving mechanisms for outflows (stellar feedback, cosmic rays, etc.). Meanwhile, comparison with simulations will decrease uncertainties in observationally-derived outflow rates. Establishing meaningful consraints on these quantities is crucial to developing a complete understanding of the processes that regulate galaxy growth. PI Schneider is an expert in numerical methodolgy and simulations of galaxy outflows. She is the primary architect of the Cholla astrophysical simulation code (Schneider 2015), and has authored several recent papers about the CGOLS project: an extremely high resolution simulation suite of galaxy outflows that will be analyzed using the techniques outlined in this proposal (Schneider 2018a, 2018b, 2020). Schneider also has experience in producing mock observables from simulation data, and has developed new techniques to produce absorption-line spectra from idealized numerical simulations (de la Cruz 2020). Co-I Hummels is an expert in modeling and analyzing galactic hydrodynamics simulations with a focus on studies of the circumgalactic medium (Hummels et al. 2012, 2013). He is the primary developer of the open-source software code Trident (Hummels et al. 2017), a core contributor to the yt code, and a member of the FIRE and Tempest simulation teams studying their circumgalactic media (Hummels et al. 2019). Co-I Chisholm has extensive expertise in using HST/COS observations to trace the properties of galactic outflows originating from a variety of different nearby star-forming galaxies (Chisholm et al. 2015; 2016a,b; 2017 a, b; 2018). Co-I Chisholm is also part of the ongoing Large HST/COS program, CLASSY, which is investigating the galactic outflow properties of 45 high-resolution, high signal-to-noise HST/COS observations. As such, Co-I Chisholm has extensive knowledge of the HST/COS archive and how to reduce and analyze the HST/COS observations that can be compared to the proposed simulated spectra. Co-I Rubin has extensive expertise in absorption-line modeling of outflows in down-the-barrel galaxy spectroscopy (Rubin et al. 2010, 2014). She has also led several works using background QSO and galaxy spectroscopy to characterize foreground circumgalactic gas (Rubin et al. 2015, Rubin et al. 2018a, b, c). Galaxies Intergalactic Medium and the Circumgalactic Medium 0 Regular false false true true false SUPPORTED