A Simulated Galaxy Laboratory: Exploring the Observational Effects on UV Spectral Absorption Line Measurements

• DOI: 10.3847/1538-4357/ad9b13
• Publication Date: 2025-01-17T08:48:58Z
• Authors: R. Michael Jennings; Alaina Henry; Valentin Mauerhofer; Timothy Heckman; Claudia Scarlata; Cody Carr; Xinfeng Xu; Mason Huberty; Simon Gazagnes; Anne E. Jaskot; Jeremy Blaizot; Anne Verhamme; Sophia R. Flury; Alberto Saldana-L...; Matthew J. Hayes; Maxime Trebitsch
• Keywords: Line (geometry); Hydrogen line

Abstract Ultraviolet absorption line spectroscopy is a sensitive diagnostic for the properties of interstellar and circumgalactic gas. Down-the-barrel observations, where measured against galaxy itself, are commonly used to study feedback from galactic outflows make predictions about leakage H i ionizing photons into intergalactic medium. Nonetheless, interpretation these observations challenging, observational compromises often made in terms signal-to-noise ratio, spectral resolution, or use stacking analyses. In this paper, we present novel quantitative assessment UV measurement techniques by using mock hydrodynamical simulation. We simulated create 22,500 spectra Si ii lines while also modeling ratio resolution recent rest-frame surveys at both high low redshifts. show that residual flux features easily overestimated single measurements stacked spectra. Additionally, explore robustness partial covering model estimating column densities find underpredictions on an average 1.25 dex. underprediction likely caused high-column-density sight optically thick dust making them invisible